EP2811110A1 - Arrangement and Method in Rock Breaking - Google Patents
Arrangement and Method in Rock Breaking Download PDFInfo
- Publication number
- EP2811110A1 EP2811110A1 EP13171043.6A EP13171043A EP2811110A1 EP 2811110 A1 EP2811110 A1 EP 2811110A1 EP 13171043 A EP13171043 A EP 13171043A EP 2811110 A1 EP2811110 A1 EP 2811110A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- rock breaking
- component
- magnetization
- breaking system
- arrangement
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000011435 rock Substances 0.000 title claims abstract description 233
- 238000000034 method Methods 0.000 title claims abstract description 14
- 230000005415 magnetization Effects 0.000 claims abstract description 143
- 230000002085 persistent effect Effects 0.000 claims abstract description 89
- 230000008859 change Effects 0.000 claims abstract description 40
- 230000007246 mechanism Effects 0.000 claims description 39
- 230000003938 response to stress Effects 0.000 claims description 9
- 239000011800 void material Substances 0.000 claims description 5
- 230000008878 coupling Effects 0.000 claims description 3
- 238000010168 coupling process Methods 0.000 claims description 3
- 238000005859 coupling reaction Methods 0.000 claims description 3
- 238000005259 measurement Methods 0.000 description 41
- 238000005553 drilling Methods 0.000 description 36
- 238000011010 flushing procedure Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 239000012811 non-conductive material Substances 0.000 description 2
- 238000003672 processing method Methods 0.000 description 2
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B44/00—Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/02—Drilling rigs characterised by means for land transport with their own drive, e.g. skid mounting or wheel mounting
- E21B7/025—Rock drills, i.e. jumbo drills
Definitions
- the invention relates to measurement of rock breaking dynamics.
- Stresses appearing during rock breaking in a rock breaking system may be measured and employed in controlling the rock breaking.
- F169680 and US 4,671,366 disclose an example of measuring stress waves appearing during rock breaking and employing the measured stress waves in controlling the operation of a rock breaking device.
- DE19932838 and US 6,356,077 disclose a signal processing method and device for determining a parameter of a stress wave by measuring magnetoelastic changes caused by stress waves in a component subjected to percussive loads.
- An object of the present invention is to provide a novel arrangement and method for measuring rock breaking dynamics.
- an arrangement for measuring rock breaking dynamics comprises at least one component of a rock breaking system, the component being subjected to stress during rock breaking, at least one element at least part of which is arranged to a state of persistent magnetization, and at least one measuring member for measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component.
- At least part of the element is arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- the element is a permanent magnet arranged to provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- the permanent magnet is arranged to continuously provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- a permanent magnet is arranged to intermittently provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- the arrangement comprises a number of permanent magnets arranged to at least partly surround the component of the rock breaking system.
- a single permanent magnet or a group of permanent magnets is arranged to provide at least partly circumferential structure.
- a single permanent magnet or a group of permanent magnets is openable.
- a single permanent magnet or a group of permanent magnets is openable for arranging the structure of the single permanent magnet or the group of permanent magnets around the component of the rock breaking system.
- a single permanent magnet or a group of permanent magnets is arranged to provide a circumferential structure, which is openable for arranging the single permanent magnet or the group of permanent magnets around the component of the rock breaking system.
- the element at least part of which is arranged into the state of persistent magnetization is the component of the rock breaking system.
- the arrangement comprises magnetization means for arranging at least part of the component of the rock breaking system into the state of persistent magnetization.
- the magnetization means is configured to provide an electromagnetic pulse for arranging at least part of the component of the rock breaking system into the state of persistent magnetization.
- the magnetization means is arranged to at least partly surround the component of the rock breaking system.
- the magnetization means is arranged to provide at least partly circumferential structure.
- the magnetization means is openable.
- the magnetization means is openable for arranging the structure of the magnetization means at least partially around the component of the rock breaking system.
- the magnetization means is arranged to provide at least partly circumferential structure, which is openable for arranging the magnetization means at least partially around the component of the rock breaking system.
- the magnetization means is configured to arrange at least part of the component of the rock breaking system into the state of persistent magnetization at intervals.
- At least part of the component of the rock breaking system is arranged into the state of persistent magnetization prior to use of the component in the rock breaking system.
- the rock breaking system comprises at least one void into which at least one permanent magnet or magnetization means is arranged.
- the component of the rock breaking system is one of a tool, a drill rod, a drill bit, a component of an impact mechanism such as a frame structure of the impact mechanism, an impact device, a drill shank, an attenuating device, an adapter and a coupling sleeve.
- a method for measuring rock breaking dynamics comprises arranging at least part of a component of a rock breaking system into a state of persistent magnetization, the component being subjected to stress during rock breaking, and measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component.
- At least part of the component of the rock breaking system is arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- At least part of the component of the rock breaking system is arranged into the state of persistent magnetization by at least one permanent magnet, by magnetization means comprising at least one permanent magnet or by magnetization means providing an electromagnetic pulse.
- At least part of the component of the rock breaking system is arranged into the state of persistent magnetization at intervals.
- a measuring instrument comprises at least one magnetization means for arranging at least part of an object into a state of persistent magnetization, and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
- the measuring instrument comprises means configured to provide an electromagnetic pulse for arranging at least part of the object into the state of persistent magnetization.
- the magnetization means is configured to arrange at least part of the object into the state of persistent magnetization at intervals.
- the magnetization means comprises at least one permanent magnet.
- the magnetization means comprises a number of permanent magnets to be arranged to at least partly surround the object.
- a single permanent magnet or a group of permanent magnets is arranged to provide at least partly circumferential structure.
- the single permanent magnet or a group of permanent magnets is openable.
- the method comprises arranging at least part of the object into a state of persistent magnetization and measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
- an electromagnetic pulse is provided for arranging at least part of the object into the state of persistent magnetization.
- At least part of the object is arranged into the state of persistent magnetization at intervals.
- the object is arranged into the state of persistent magnetization by at least one permanent magnet, by magnetization means comprising at least one permanent magnet or by magnetization means providing an electromagnetic pulse.
- Rock breaking may be performed by drilling holes in a rock by a rock drilling machine.
- rock may be broken by a breaking hammer.
- the rock drilling machine and breaking hammer comprise an impact mechanism, which provides impact pulses to the tool either directly or through an adapter.
- the impact pulse generates a stress wave which propagates in the tool.
- the stress wave reaches the end of the tool facing the rock to be drilled, the tool penetrates into the rock due to the influence of the wave.
- Some of the energy of the stress wave may reflect back as a reflected wave, which propagates in the opposite direction in the tool, i.e. towards the impact mechanism.
- the reflected wave may comprise only a compression stress wave or a tensile stress wave.
- the reflected wave typically comprises both tension and compression stress components.
- FIG. 1 shows schematically a significantly simplified side view of a rock drilling rig 1.
- the rock drilling rig 1 comprises a moving carrier 2 and a boom 3 at the end of which there is a feed beam 4 provided with a rock drilling machine 8 having an impact mechanism 5 and a rotating mechanism 6.
- the rock drilling rig 1 of Figure 1 further comprises a tool 9, the proximal end of which is coupled to the rock drilling machine 8 and the distal end of which is oriented towards the rock 12 to be drilled.
- the proximal end 9' of the tool 9 is shown in Figure 1 schematically by a broken line.
- the tool 9 of the rock drilling rig 1 of Figure 1 comprises drill rods 10a, 10b and 10c and a drill bit 11 at the distal end 9" of the tool 9.
- the drill bit 11 may be provided with buttons 11a, although other drill bit structures are also possible.
- sectional drill rods also known as long hole drilling
- a number of drill rods depending on the depth of the hole to be drilled are attached between the drill bit 11 and the rock drilling machine 8.
- the tool 9 may also be supported with guide supports 13 attached to the feed beam 4.
- the drilling machine may also have a structure other than explained above.
- the impact mechanism is located in the drilling machine at the bottom of the drilling hole next to the drill bit, the drill bit being connected through the drill rods to the rotating mechanism located above the drilling hole.
- the impact mechanism 5 may be provided with an impact piston reciprocating under the influence of pressure medium and striking to the tool either directly or through an intermediate piece, such as a drill shank or another kind of adapter, between the tool 9 and the impact piston.
- an impact mechanism of a different structure is also possible.
- the operation of the impact mechanism 5 may thus also be based on use of electromagnetism or hydraulic pressure without any mechanically reciprocating impact piston and in this context the term impact mechanism refers also to impact devices based on such characteristics.
- the stress wave generated by the impact mechanism 5 is delivered along the drill rods 10a to 10c towards the drill bit 11 at the distal end of the tool 9.
- the drill bit 11 and its buttons 11a strike the rock 12 to be drilled, thereby causing to the rock 12 to be drilled a strong stress due to which cracks are formed in the rock 12.
- part of the stress wave exerted on or acting on the rock 12 reflects back to the tool 9 and along the tool 9 back towards the impact mechanism 5.
- Figure 2 shows schematically a stress wave, wherein the stress wave propagating towards the rock 12 to be drilled is denoted with a reference mark s i and the stress wave reflected from the rock 12 back to the tool 9 is denoted with a reference mark s r .
- the rock drilling rig 1 of Figure 1 also comprises a feed mechanism 7, which is arranged to the feed beam 4, in relation to which the rock drilling machine 8 is movably arranged.
- the feed mechanism 7 is arranged to push the rock drilling machine 8 forward on the feed beam 4 and thus to push the drill bit 11 against the rock 12.
- Figure 1 shows the rock drilling rig 1 considerably smaller in relation to the structure of the rock drilling machine 8 than what it is in reality.
- the rock drilling rig 1 of Figure 1 has only one boom 3, feed beam 4, rock drilling machine 8 and feed mechanism 7, although it is obvious that a rock drilling rig may be provided with a plurality of booms 3 having a feed beam 4, a rock drilling machine 8 and a feed mechanism 7.
- the rock drilling machine 8 usually includes flushing means to prevent the drill bit 11 from being blocked.
- no flushing means are shown in Figure 1 .
- the drilling machine 8 may be hydraulically operated, but it may also be pneumatically or electrically operated.
- FIG 3 shows schematically a partly cross-sectional side view of a rock breaking system 14 which may be used, for example, in the rock drilling rig of Figure 1 .
- the rock breaking system 14 of Figure 3 comprises an impact mechanism 5 and a tool 9 connected to the impact mechanism 5.
- the tool 9 in the rock breaking system 14 of Figure 3 comprises drill rods 10a, 10b and a drill bit 11 at the distal end of the drill rod 10b.
- the impact mechanism 5 comprises a frame structure 5' and an impact device 15 arranged to provide impact pulses directed to the tool 9.
- the impact device 15 has a form of an impact piston but the actual implementation of the impact device 15 and the impact mechanism 5 may vary in many ways.
- the impact mechanism 5 of Figure 3 also comprises a drill shank 16 to which the proximal end 9' of the tool 9 is fastened, whereby the impact device 15 is arranged to direct the impact to the drill shank 16 and not directly to the tool 9, the drill shank 16 thus forming an intermediate piece between the impact device 15 and the tool 9.
- the impact mechanism 5 of Figure 3 further comprises an attenuating device 17, which is shown very schematically in Figure 3 and which is positioned between the drill shank 16 and the impact device 15 and supported to the frame structure 5' of the impact mechanism 5. The function of the attenuating device 17 is to attenuate effects of stresses reflecting back to the tool 9 and the impact mechanism 5 from the rock 12.
- the attenuating device 17 may also provide positioning of the drill shank 16 at such a point relative to the impact device 15 that the impact provided by the impact device 15 will have an optimal effect on the drill shank 16.
- the actual implementation of the attenuating device 17 may comprise for example one or more pressure medium operated cylinders.
- the impact mechanism 5 and the tool 9 coupled to the impact mechanism 5 form the rock breaking system 14, which is subjected to stresses during rock breaking.
- An implementation of the rock breaking system may, however, vary in many ways.
- the rock breaking system comprises typically only an impact device and a tool such that the impact provided by the impact device affects straight to the tool 9.
- the rock breaking system may be hydraulically, pneumatically or electrically operated or the operation of the rock breaking system may be implemented as a combination of hydraulically, pneumatically and/or electrically operated devices.
- Figures 1 and 3 do not show any pressure medium lines or electrical lines needed for the operation of the rock breaking system, which lines are as such known to the person skilled in the art.
- Figure 4 discloses schematically some possible locations where one or more permanent magnets 18 may be located in the rock breaking system 14 of Figure 3 .
- the permanent magnets 18 are elements which are or can be arranged into a state of persistent magnetization.
- the permanent magnets 18 When the permanent magnets 18 are arranged into the state of persistent magnetization, they have a magnetic field, and when at least part of the component of the rock breaking system 14 is subjected to the effect of the magnetic field of at least one permanent magnet 18, at least part of the component of the rock breaking system 14 is further arranged into a state of persistent magnetization.
- stress when stress is acting on the component arranged into the state of persistent magnetization during rock breaking, or in other words, when stress affects the component of the rock breaking system arranged into the state of persistent magnetization, the stress causes a change in a magnetic property of the component.
- the component of the rock breaking system 14, at least part of which may be arranged into the state of persistent magnetization may for example be the impact mechanism 5, the frame structure 5' of the impact mechanism 5, the impact device 15, the drill shank 16, the attenuating device 17, the tool 9 of the rock breaking system 14 such as the drill rods 10a, 10b, 10c and/or the drill bit 11.
- the component of the rock breaking system 14, at least part of which may be arranged into the state of persistent magnetization may also be an adapter or a coupling sleeve in the impact mechanism, for example.
- the components of the rock breaking system 14 which may be arranged into the state of persistent magnetization are thus components which may generate, convey or damp the stresses or the stress waves appearing during rock breaking.
- the state of persistent magnetization may be a state of magnetization that remains for a relatively long period of time as in a permanent magnet, a state of magnetization that is maintained by intermittent application of an external magnetic source, a state of magnetization remaining internally in the component material resulting from exposure to an external magnetic field, or a state of persistent magnetization that need not be maintained with an external magnetic source during a measurement period. It is possible that the state of persistent magnetization is provided by a single intermittent application of a magnetic source either by active means, some examples of which are provided later, or by non-active means, such as a permanent magnet. Also arranging a component into a non-magnetic state is in this context considered to correspond to arranging the component into the state of persistent magnetization.
- the change in the magnetic property of the component may be a change in a magnetic field of the component, a change in a magnetic flux of the magnetic field of the component, a change in a permeability or magnetic inductivity of the component or a change in a state or intensity of magnetization of the component, for example.
- the change in the magnetic property of the component is thus a consequence of a change in the state of the material of the component being subjected to stress. Because the solution deals with the state of persistent magnetization, changes in the magnetic property of the component subjected to stress can be detected more consistently.
- the permanent magnets 18 are fastened in a supporting structure 19 and have a circular form so that the permanent magnets 18 may be arranged to surround the component at least part of which will be arranged into a state of persistent magnetization with at least one permanent magnet 18.
- the permanent magnets 18 are arranged to surround the rod 10a of the tool 9, the drill shank 16, the attenuating device 17 and the impact device 15.
- Figure 5 discloses schematically some further possible locations where one or more permanent magnets 18 may be located in the rock breaking system 14 of Figure 3 .
- the permanent magnets also have the circular shape but the supporting structures 19 disclosed in Figure 4 have been left out.
- the interior of the drill rod 10a forms a kind of void wherein at least one permanent magnet 18 may be arranged.
- the permanent magnet 18 may be located in a flushing channel 31 of the drill shank 16, for example, the flushing channel forming a kind of void in the drill shank 16.
- Figures 4 and 5 show schematically some possible locations where the permanent magnets 18 may be arranged in the rock breaking system 14.
- the arrangement may, however, comprise only one permanent magnet 18 to arrange at least part of one rock breaking system component into the state of persistent magnetization.
- the arrangement may comprise two or more permanent magnets 18 to arrange at least part of one or more rock breaking system components into the state of persistent magnetization. Therefore in the arrangement there may be several rock breaking system components each having a relating permanent magnet 18 or one or more rock breaking system components having several relating permanent magnets 18.
- Figures 4 and 5 Examples of the latter embodiment are also shown schematically in Figures 4 and 5, Figure 4 disclosing two successive permanent magnets 18 surrounding the drill shank 16 and Figure 5 disclosing two successive permanent magnets 18 arranged in the void 20 in the frame structure 5' of the impact mechanism 5.
- the permanent magnets may also be arranged to be successive in relation to each other in the circumferential direction of the specific rock breaking system component.
- the permanent magnets may have a form of a rectangle, for example.
- the permanent magnets are arranged permanently in the vicinity of the rock breaking system components, the permanent magnets are thus arranged to continuously provide at least part of the component of the rock breaking system into the state of persistent magnetization in the examples of Figures 4 and 5 .
- Figures 4 and 5 disclose schematically also means for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the rock breaking system component, the change in the magnetic property of the component originating from the stress, such as the stress wave, affecting the component of the rock breaking system 14 during the operation of the rock breaking system 14.
- the measuring member for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component is a measurement coil 21, which in the embodiment of Figure 4 is arranged to surround the drill rod 10a, in the area of the drill rod 10a arranged into the state of persistent magnetization by the permanent magnet 18 next to the drill rod 10a.
- the measurement coil 21 could, however, alternatively be arranged next to some other rock breaking system component in the area of the component arranged into the state of persistent magnetization by the permanent magnet 18.
- the measuring member for measuring the change in the magnetic property of the component is a magnetic sensor 22, which in the embodiment of Figure 5 is arranged in the drill shank 16, in the area of the drill shank 16 arranged into the state of persistent magnetization by the permanent magnet 18 in the drill shank 16.
- the magnetic sensor 22 could, however, alternatively be in some other rock breaking system component in the area of the component arranged into the state of persistent magnetization.
- the magnetic sensor 22 may, for example, be a coil, a magnetometer, a magnetoresistive element or a Hall-sensor.
- the measurement information provided by the measuring member is transferred, either through a wired connection or a wireless connection, schematically indicated by arrow 23, to a data processing unit 24.
- the data processing unit 24 comprises software- and/or hardware-based means for processing or modifying the measurement information provided by the measuring member to reach a meaningful representation of the measurement information provided by the measuring member such that the measurement information may be analysed and/or used for controlling the operation of the rock breaking system 14 or the whole rock drilling rig 1 or the breaking hammer.
- the processing or modification methods disclosed in DE19932838 and US 6,356,077 may be applied.
- instruments relating to the measurement operation are preferably manufactured of electrically non-conductive material. Possible coils, however, are naturally made of electrically conductive material.
- Figure 6 shows schematically a partly cross-sectional side view of a magnetizing means structure 27 intended to arrange at least part of the rock breaking system component into the state of persistent magnetization
- Figure 7 shows schematically a partly cross-sectional end view of the magnetizing means structure 27 of Figure 6 .
- the magnetizing means structure 27 comprises a single permanent magnet 18, which in the embodiment of Figures 6 and 7 has a shape of a ring which is arranged to surround the rock breaking system component, i.e. the drill rod 10a, in the example of Figures 6 and 7 .
- the permanent magnet 18 is inserted inside the supporting structure 19 comprising a jacket 25 surrounding the permanent magnet 18 and end plates 26 so that the supporting structure 19 is a closed structure enclosing the permanent magnet 18 inside the supporting structure 19.
- At least one of the end plates 26 may be detachable for inserting the permanent magnet 18 inside the supporting structure 19.
- the supporting structure 19 forms a guiding member for guiding the magnetic field provided by the permanent magnet 18 to the rock breaking system component for arranging at least part of the rock breaking system component into the state of persistent magnetization by the magnetic field provided by the permanent magnet 18.
- the ring-shaped permanent magnet 18 is arranged to entirely surround the rock breaking system component, i.e. the drill rod 10a.
- the permanent magnet 18 surrounding either partly or entirely the rock breaking system component under interest could also have another curvilinear shape.
- the shape or form of the permanent magnet 18 surrounding at least partly the rock breaking system component under interest may also have other kind of at least partly circumferential shape than the curvilinear or annular form.
- the measurement sensor 22 is also arranged inside the inner periphery of the permanent magnet 18.
- the embodiment of Figures 6 and 7 thus provides a combination of the permanent magnet 18, i.e. the element at least part of which is arranged into the state of persistent magnetization, and the measuring member, i.e. the measurement sensor 22.
- the ends of the measurement sensor 22 may be arranged to run through the end plates 26, for example, if the measurement sensor 22 has a form of a coil.
- Figure 8 shows schematically a partly cross-sectional end view of a second magnetizing means structure 27.
- the lineation indicating the cross-section of the jacket 25 has not been shown in Figure 8 .
- the ring-shaped permanent magnet 18 of Figure 6 is replaced by a number of permanent magnets 18 having a shape of a round bar and arranged adjacently to each other in the jacket 25 of the supporting structure 19 in such a way that that the permanent magnets 18 are arranged to surround the whole periphery of the rock breaking system component, i.e. the drill rod 10a, under interest.
- Figure 9 shows schematically a partly cross-sectional end view of a third magnetizing means structure 27.
- the lineation indicating the cross-section of the jacket 25 has not been shown in Figure 9 .
- the ring-shaped permanent magnets 18 having a shape of a round bar are arranged adjacent to each other in the jacket 25 of the supporting structure 19 in such a way that the permanent magnets 18 are arranged to surround only a part of the periphery of the rock breaking system component, i.e. the drill rod 10a, under interest.
- the cross-sectional shape of the bar-like permanent magnets may also differ from the round shape.
- Figure 10 shows schematically a partly cross-sectional end view of a fourth magnetizing means structure 27.
- the magnetizing means structure 27 of Figure 10 has two portions 27', 27", each comprising the supporting structure 19, the permanent magnet 18 and the measurement sensor 22 having a shape of semiarch.
- the two portions 27', 27" may be combined, for example by using a joint hinge, with each other to form one magnetizing means structure 27 having a round form by placing the portions against each other.
- the measurement sensors 22 may also be connected together.
- the portions 27', 27" in Figure 10 are shown to have a small distance between them and no joint hinge is shown in Figure 10 .
- the magnetizing means structure 27 of Figure 10 may be assembled around the rock breaking system component not only from the end of the component but also from the side of the component.
- a group of two permanent magnets is arranged together to form a circumferential structure, which is openable for arranging the group of permanent magnets around the component of the rock breaking system.
- the two permanent magnets form, in practice, a single permanent magnet arranged around the rock breaking system component.
- permanent magnets having a shape or a form differing from the circumferential structure may be arranged in some way openable.
- a measuring member may be arranged openable in a similar way as explained in the specification relating to Figure 10 .
- the structure of the magnetization means and/or measuring member is openable, it is openable in a way to enable placement in the vicinity of the rock breaking system or to at least partly surround the rock breaking system. It may also be openable for maintenance and service purposes of the magnet(s), magnetization means, rock breaking system or the rock breaking device, such as a drill rig.
- the permanent magnet 18 or permanent magnets 18 may be manufactured of electrically conductive material without harmful deteriorating effect to the measurement of rock breaking dynamics if the jacket 25 is made of electrically non-conductive material.
- the magnetization means structure 27 provides or forms a measuring instrument for measuring a change in a magnetic property of an object, the measuring instrument comprising at least one magnetization means for arranging at least part of the object into a state of persistent magnetization and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object, the object being the drill rod 10a in the examples of Figures 6 to 10 .
- the measuring instrument thus comprises both at least one magnetization means for arranging at least part of the object into a state of persistent magnetization and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
- the magnetization means may be, for example, a permanent magnet 18, as disclosed above, or a magnetizing coil 28 or a combination of one or more permanent magnets 18 and the magnetizing coil 28, as disclosed later.
- the measuring member may be, for example, a measurement coil 21 or a magnetic sensor 22, as disclosed above.
- the structure of the measuring instrument may be openable as disclosed above in the example of Figure 10 and the relating description, for example. In the examples of this specification the measuring instrument is used for measuring changes in the magnetic property of the component of the rock breaking system 14, but generally, the measuring instrument disclosed may also be used for measuring changes in the magnetic property of other objects subjected to stress.
- the element, at least part of which is arranged into the state of persistent magnetization is thus the permanent magnet, the magnetic field of the permanent magnet, in turn, arranging at least part of the component of the rock breaking system into the state of persistent magnetization.
- the element, at least part of which is arranged into the state of persistent magnetization may also be the component of the rock breaking system, i.e.
- the component of the rock breaking system When at least part of the component of the rock breaking system is arranged into the state of persistent magnetization the component itself is arranged into a state of persistent magnetization, whereby the component itself has a magnetic property, the change of which is measured, for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component.
- Figure 11 discloses magnetizing coils 28 used as magnetizing means, which may be used to arrange at least part of the component of the rock breaking system 14 into the state of persistent magnetization.
- one or more magnetizing coils 28 are arranged to surround the drill rod 10a, the drill shank 16, the attenuating device 17 and the impact device 15.
- One or more magnetizing coils 28 may also be arranged to surround the frame structure of the impact device 5.
- the drill rod 10a, the attenuating device 17 and the impact device 5 are surrounded by only one magnetizing coil 28 but they could also be surrounded by two or more magnetizing coils 28.
- the magnetizing coils 28 could also be inserted in voids provided in the rock breaking system components in a similar way as the permanent magnets in the example of Figure 5 .
- the change in the magnetic property of the component of the rock breaking system 14 may be measured for example as explained in the examples of Figures 4 and 5 .
- the arrangement in Figure 11 comprises also a power source 29 configured to provide the necessary electric power for the magnetization coils 28 through the connections presented by arrows 30.
- the power source 29 is configured to provide an electromagnetic pulse in order to arrange at least part of the component of the rock breaking system 14 into the state of persistent magnetization.
- the length, shape and amplitude of the electromagnetic pulse may be fixed or variable.
- the component of the rock breaking system 14 may be arranged into the state of persistent magnetization at intervals, for example at regular intervals, on the basis of an operating state of the rock breaking system 14, on the basis of operation of the measuring member or on the basis of a change in the magnetic property of the component of the rock breaking system 14. At least part of the component of the rock breaking system 14 may be arranged into the state of persistent magnetization also prior to use of the component in the rock breaking system 14.
- the time periods may be related to absolute time, rock breaking time, work shift durations and so on.
- the interval may also be defined on the basis of rock breaking operations, such as a drilled distance, a number of impacts subjected to the tool 9, an amount of impact energy or energy in general travelled through the tool 9 and so on.
- An interval may also be used for making magnetization operations occur at least within the interval. That is, if magnetization operations have not taken place during a defined interval, magnetization operations are executed.
- the magnetization operations may be executed, for example, during an idle state of the impact device 15, such as between successive impacts, between impact series, upon beginning to drill a hole, during a change of a new drill rod 10a, upon finishing a hole, during positioning the rock breaking system for drilling a hole, during movement of the rock breaking system or device, such as the rock drilling rig 1, at the rock breaking site.
- the magnetization operations may be executed during an idle state of the measuring member, or, for example when it is observed that quality of measurement suffers from improper state of magnetization.
- the magnetization operations may also be executed on the basis of a measured value or measurement result.
- the measured value or measurement result may be obtained from an additional sensor, possibly external to the rock breaking system or the measurement system.
- the magnetization operations may be executed when it is observed that the state of persistent magnetization has changed to such an extent that no reliable measurement information cannot be obtained.
- At least part of the component may be arranged into the state of persistent magnetization for example after the manufacturing of the component, before assembling the component to the rock breaking system either at the factory or use site of the rock breaking system, or after assembling the component to the rock breaking system but before the actual operation of the rock breaking system. At least part of the component of the rock breaking system may thus be arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- the operation of the magnetization may be controlled for example with the data processing unit 24.
- the component of the rock breaking system is arranged into the state of persistent magnetization by using only the magnetization coil 28 as the magnetization means. It is however possible that a permanent magnet is arranged in combination with the magnetization coil 28. It is also possible that instead of using the magnetization coil 28 only a permanent magnet is used for arranging the specific component of the rock breaking system into the state of persistent magnetization by arranging the permanent magnet in the vicinity of the specific rock breaking system component only for a specific time period as explained above. Thus also only the permanent magnet may be used to intermittently provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- the component of the rock breaking system When at least part of the component of the rock breaking system is arranged into the state of persistent magnetization, which state of persistent magnetization may be stimulated if necessary, the component of the rock breaking system itself provides the magnetic property which is observed when the parameter of rock breaking dynamics is measured on the basis of the change in the magnetic property of the component.
- disturbances do not appear either in the measurement of the changes in the magnetic property of the rock breaking system component due to the stress acting on the rock breaking system component, which disturbances take place in prior art solutions comprising a magnetizing coil to magnetize the rock breaking system component simultaneously during the measurement of the changes in the magnetic property of the rock breaking system component.
- the magnetization coil 28 may be used as a measurement coil too.
- the magnetization coil 28 may be used both for providing the electromagnetic pulse for arranging a component of the rock breaking system into the state of persistent magnetization and for providing a measurement of a parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component after the component has been arranged into the state of persistent magnetization, i.e. at the time the magnetization coil 28 is not used for arranging the component of the rock breaking system into the state of persistent magnetization.
- Figures 12 and 13 show schematically an example of a measurement result of a stress wave, Figure 13 being more detailed presentation of the first part of the measurements of Figure 12 .
- the dashed line represents the stress wave measured by a strain gauge attached to a rock breaking system component.
- the continuous line represents the same stress wave measured by a measurement coil when permanent magnets were used for arranging the same rock breaking system component into the state of persistent magnetization. From Figures 12 and 13 it can be seen that the stress wave measurement provided by the presented solution corresponds to the measurement provided by the strain gauge, which can be considered to follow exactly the stress wave appearing in the rock breaking system component, because the strain gauge is directly fixed to the rock breaking system component.
- Examples of the measurement arrangement disclosed above relate to the measurement of stresses or stress waves affecting the rock breaking system during rock breaking, but the measurement arrangement may also be utilized in other ways for measurement of rock breaking dynamics or related parameters.
- the measurement arrangement may also be utilized in the determination of other phenomena or events, such as determination of the impact frequency or characteristics of the broken rock, as well as in the condition monitoring of the rock breaking system or its components.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
- Percussive Tools And Related Accessories (AREA)
Abstract
Description
- The invention relates to measurement of rock breaking dynamics.
- Stresses appearing during rock breaking in a rock breaking system may be measured and employed in controlling the rock breaking. F169680 and
US 4,671,366 , disclose an example of measuring stress waves appearing during rock breaking and employing the measured stress waves in controlling the operation of a rock breaking device.DE19932838 andUS 6,356,077 disclose a signal processing method and device for determining a parameter of a stress wave by measuring magnetoelastic changes caused by stress waves in a component subjected to percussive loads. - An object of the present invention is to provide a novel arrangement and method for measuring rock breaking dynamics.
- The invention is characterized by the features of the independent claims.
- According to an embodiment, an arrangement for measuring rock breaking dynamics comprises at least one component of a rock breaking system, the component being subjected to stress during rock breaking, at least one element at least part of which is arranged to a state of persistent magnetization, and at least one measuring member for measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component.
- According to an embodiment of the arrangement, at least part of the element is arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- According to an embodiment of the arrangement, the element is a permanent magnet arranged to provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- According to an embodiment of the arrangement, the permanent magnet is arranged to continuously provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- According to an embodiment of the arrangement, a permanent magnet is arranged to intermittently provide at least part of the component of the rock breaking system into the state of persistent magnetization.
- According to an embodiment of the arrangement, the arrangement comprises a number of permanent magnets arranged to at least partly surround the component of the rock breaking system.
- According to an embodiment of the arrangement, a single permanent magnet or a group of permanent magnets is arranged to provide at least partly circumferential structure.
- According to an embodiment of the arrangement, a single permanent magnet or a group of permanent magnets is openable.
- According to an embodiment of the arrangement, a single permanent magnet or a group of permanent magnets is openable for arranging the structure of the single permanent magnet or the group of permanent magnets around the component of the rock breaking system.
- According to an embodiment of the arrangement, a single permanent magnet or a group of permanent magnets is arranged to provide a circumferential structure, which is openable for arranging the single permanent magnet or the group of permanent magnets around the component of the rock breaking system.
- According to an embodiment of the arrangement, the element at least part of which is arranged into the state of persistent magnetization is the component of the rock breaking system.
- According to an embodiment of the arrangement, the arrangement comprises magnetization means for arranging at least part of the component of the rock breaking system into the state of persistent magnetization.
- According to an embodiment of the arrangement, the magnetization means is configured to provide an electromagnetic pulse for arranging at least part of the component of the rock breaking system into the state of persistent magnetization.
- According to an embodiment of the arrangement, the magnetization means is arranged to at least partly surround the component of the rock breaking system.
- According to an embodiment of the arrangement, the magnetization means is arranged to provide at least partly circumferential structure.
- According to an embodiment of the arrangement, the magnetization means is openable.
- According to an embodiment of the arrangement, the magnetization means is openable for arranging the structure of the magnetization means at least partially around the component of the rock breaking system.
- According to an embodiment of the arrangement, the magnetization means is arranged to provide at least partly circumferential structure, which is openable for arranging the magnetization means at least partially around the component of the rock breaking system.
- According to an embodiment of the arrangement, the magnetization means is configured to arrange at least part of the component of the rock breaking system into the state of persistent magnetization at intervals.
- According to an embodiment of the arrangement, at least part of the component of the rock breaking system is arranged into the state of persistent magnetization prior to use of the component in the rock breaking system.
- According to an embodiment of the arrangement, the rock breaking system comprises at least one void into which at least one permanent magnet or magnetization means is arranged.
- According to an embodiment of the arrangement, the component of the rock breaking system is one of a tool, a drill rod, a drill bit, a component of an impact mechanism such as a frame structure of the impact mechanism, an impact device, a drill shank, an attenuating device, an adapter and a coupling sleeve.
- According to an embodiment, a method for measuring rock breaking dynamics comprises arranging at least part of a component of a rock breaking system into a state of persistent magnetization, the component being subjected to stress during rock breaking, and measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component.
- According to an embodiment of the method, at least part of the component of the rock breaking system is arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- According to an embodiment of the method, at least part of the component of the rock breaking system is arranged into the state of persistent magnetization by at least one permanent magnet, by magnetization means comprising at least one permanent magnet or by magnetization means providing an electromagnetic pulse.
- According to an embodiment of the method, at least part of the component of the rock breaking system is arranged into the state of persistent magnetization at intervals.
- According to an embodiment of a measuring instrument, a measuring instrument comprises at least one magnetization means for arranging at least part of an object into a state of persistent magnetization, and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
- According to an embodiment of the measuring instrument, the measuring instrument comprises means configured to provide an electromagnetic pulse for arranging at least part of the object into the state of persistent magnetization.
- According to an embodiment of the measuring instrument, the magnetization means is configured to arrange at least part of the object into the state of persistent magnetization at intervals.
- According to an embodiment of the measuring instrument, the magnetization means comprises at least one permanent magnet.
- According to an embodiment of the measuring instrument, the magnetization means comprises a number of permanent magnets to be arranged to at least partly surround the object.
- According to an embodiment of the measuring instrument, a single permanent magnet or a group of permanent magnets is arranged to provide at least partly circumferential structure.
- According to an embodiment of the measuring instrument, the single permanent magnet or a group of permanent magnets is openable.
- According to an embodiment of a measuring method relating to measuring a change in the magnetic property of an object in response to stress exerted on the object, the method comprises arranging at least part of the object into a state of persistent magnetization and measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
- According to an embodiment of the measuring method relating to measuring the change in the magnetic property of the object in response to stress exerted on the object, an electromagnetic pulse is provided for arranging at least part of the object into the state of persistent magnetization.
- According to an embodiment of the measuring method relating to measuring the change in the magnetic property of the object in response to stress exerted on the object, at least part of the object is arranged into the state of persistent magnetization at intervals.
- According to an embodiment of the measuring method relating to measuring the change in the magnetic property of the object in response to stress exerted on the object, the object is arranged into the state of persistent magnetization by at least one permanent magnet, by magnetization means comprising at least one permanent magnet or by magnetization means providing an electromagnetic pulse.
- In the following the invention will be described in greater detail by means of preferred embodiments, with reference to the accompanying drawings, in which
-
Figure 1 shows schematically a side view of a rock drilling rig; -
Figure 2 shows schematically a stress wave appearing in rock drilling; -
Figure 3 shows schematically a partly cross-sectional side view of a rock breaking system; -
Figure 4 shows schematically a partly cross-sectional side view of an arrangement for arranging a component of the rock breaking system into a state of persistent magnetization; -
Figure 5 shows schematically another partly cross-sectional side view of a second arrangement for arranging a component of the rock breaking system into a state of persistent magnetization; -
Figure 6 shows schematically a partly cross-sectional side view of a magnetizing means structure; -
Figure 7 shows schematically a partly cross-sectional end view of the magnetizing means structure ofFigure 6 ; -
Figure 8 shows schematically a partly cross-sectional end view of a second magnetizing means structure; -
Figure 9 shows schematically a partly cross-sectional end view of a third magnetizing means structure; -
Figure 10 shows schematically a partly cross-sectional end view of a fourth magnetizing means structure; -
Figure 11 shows schematically a partly cross-sectionalized side view of a third arrangement for arranging a component of the rock breaking system into a state of persistent magnetization; and -
Figures 12 and 13 show schematically an example of a measurement result of a stress wave. - Rock breaking may be performed by drilling holes in a rock by a rock drilling machine. Alternatively, rock may be broken by a breaking hammer. In this context, the term "rock" is to be understood broadly to cover also a boulder, rock material, crust and other relatively hard material. The rock drilling machine and breaking hammer comprise an impact mechanism, which provides impact pulses to the tool either directly or through an adapter. The impact pulse generates a stress wave which propagates in the tool. When the stress wave reaches the end of the tool facing the rock to be drilled, the tool penetrates into the rock due to the influence of the wave. Some of the energy of the stress wave may reflect back as a reflected wave, which propagates in the opposite direction in the tool, i.e. towards the impact mechanism. Depending on the situation, the reflected wave may comprise only a compression stress wave or a tensile stress wave. However, the reflected wave typically comprises both tension and compression stress components.
-
Figure 1 shows schematically a significantly simplified side view of arock drilling rig 1. Therock drilling rig 1 comprises a movingcarrier 2 and aboom 3 at the end of which there is afeed beam 4 provided with arock drilling machine 8 having animpact mechanism 5 and arotating mechanism 6. Therock drilling rig 1 ofFigure 1 further comprises atool 9, the proximal end of which is coupled to therock drilling machine 8 and the distal end of which is oriented towards therock 12 to be drilled. The proximal end 9' of thetool 9 is shown inFigure 1 schematically by a broken line. Thetool 9 of therock drilling rig 1 ofFigure 1 comprisesdrill rods drill bit 11 at thedistal end 9" of thetool 9. Thedrill bit 11 may be provided withbuttons 11a, although other drill bit structures are also possible. In drilling with sectional drill rods, also known as long hole drilling, a number of drill rods depending on the depth of the hole to be drilled are attached between thedrill bit 11 and therock drilling machine 8. Thetool 9 may also be supported with guide supports 13 attached to thefeed beam 4. - The drilling machine may also have a structure other than explained above. For example in down-the-hole-drilling the impact mechanism is located in the drilling machine at the bottom of the drilling hole next to the drill bit, the drill bit being connected through the drill rods to the rotating mechanism located above the drilling hole.
- The
impact mechanism 5 may be provided with an impact piston reciprocating under the influence of pressure medium and striking to the tool either directly or through an intermediate piece, such as a drill shank or another kind of adapter, between thetool 9 and the impact piston. Naturally an impact mechanism of a different structure is also possible. The operation of theimpact mechanism 5 may thus also be based on use of electromagnetism or hydraulic pressure without any mechanically reciprocating impact piston and in this context the term impact mechanism refers also to impact devices based on such characteristics. The stress wave generated by theimpact mechanism 5 is delivered along thedrill rods 10a to 10c towards thedrill bit 11 at the distal end of thetool 9. When the stress wave meets thedrill bit 11, thedrill bit 11 and itsbuttons 11a strike therock 12 to be drilled, thereby causing to therock 12 to be drilled a strong stress due to which cracks are formed in therock 12. Typically part of the stress wave exerted on or acting on therock 12 reflects back to thetool 9 and along thetool 9 back towards theimpact mechanism 5. -
Figure 2 shows schematically a stress wave, wherein the stress wave propagating towards therock 12 to be drilled is denoted with a reference mark si and the stress wave reflected from therock 12 back to thetool 9 is denoted with a reference mark sr. - During drilling the
rotating mechanism 6 transmits continuous rotating force to thetool 9, thus causing thebuttons 11a of thedrill bit 11 to change their position after an impact and to strike a new spot on therock 12 at the next impact. Therock drilling rig 1 ofFigure 1 also comprises afeed mechanism 7, which is arranged to thefeed beam 4, in relation to which therock drilling machine 8 is movably arranged. During drilling thefeed mechanism 7 is arranged to push therock drilling machine 8 forward on thefeed beam 4 and thus to push thedrill bit 11 against therock 12. -
Figure 1 shows therock drilling rig 1 considerably smaller in relation to the structure of therock drilling machine 8 than what it is in reality. For the sake of clarity, therock drilling rig 1 ofFigure 1 has only oneboom 3,feed beam 4,rock drilling machine 8 andfeed mechanism 7, although it is obvious that a rock drilling rig may be provided with a plurality ofbooms 3 having afeed beam 4, arock drilling machine 8 and afeed mechanism 7. It is also obvious that therock drilling machine 8 usually includes flushing means to prevent thedrill bit 11 from being blocked. For the sake of clarity, no flushing means are shown inFigure 1 . Thedrilling machine 8 may be hydraulically operated, but it may also be pneumatically or electrically operated. -
Figure 3 shows schematically a partly cross-sectional side view of arock breaking system 14 which may be used, for example, in the rock drilling rig ofFigure 1 . Therock breaking system 14 ofFigure 3 comprises animpact mechanism 5 and atool 9 connected to theimpact mechanism 5. Thetool 9 in therock breaking system 14 ofFigure 3 comprisesdrill rods drill bit 11 at the distal end of thedrill rod 10b. Theimpact mechanism 5 comprises a frame structure 5' and animpact device 15 arranged to provide impact pulses directed to thetool 9. In the embodiment ofFigure 3 theimpact device 15 has a form of an impact piston but the actual implementation of theimpact device 15 and theimpact mechanism 5 may vary in many ways. Theimpact mechanism 5 ofFigure 3 also comprises adrill shank 16 to which the proximal end 9' of thetool 9 is fastened, whereby theimpact device 15 is arranged to direct the impact to thedrill shank 16 and not directly to thetool 9, thedrill shank 16 thus forming an intermediate piece between theimpact device 15 and thetool 9. Theimpact mechanism 5 ofFigure 3 further comprises an attenuatingdevice 17, which is shown very schematically inFigure 3 and which is positioned between thedrill shank 16 and theimpact device 15 and supported to the frame structure 5' of theimpact mechanism 5. The function of the attenuatingdevice 17 is to attenuate effects of stresses reflecting back to thetool 9 and theimpact mechanism 5 from therock 12. The attenuatingdevice 17 may also provide positioning of thedrill shank 16 at such a point relative to theimpact device 15 that the impact provided by theimpact device 15 will have an optimal effect on thedrill shank 16. The actual implementation of the attenuatingdevice 17 may comprise for example one or more pressure medium operated cylinders. - In the embodiment of
Figure 3 theimpact mechanism 5 and thetool 9 coupled to theimpact mechanism 5 form therock breaking system 14, which is subjected to stresses during rock breaking. An implementation of the rock breaking system may, however, vary in many ways. In breaking hammers, for example, the rock breaking system comprises typically only an impact device and a tool such that the impact provided by the impact device affects straight to thetool 9. Depending on the implementation the rock breaking system may be hydraulically, pneumatically or electrically operated or the operation of the rock breaking system may be implemented as a combination of hydraulically, pneumatically and/or electrically operated devices. For the sake of clarity,Figures 1 and3 do not show any pressure medium lines or electrical lines needed for the operation of the rock breaking system, which lines are as such known to the person skilled in the art. -
Figure 4 discloses schematically some possible locations where one or morepermanent magnets 18 may be located in therock breaking system 14 ofFigure 3 . For the sake of clarity, the frame structure 5' of theimpact mechanism 5 is omitted inFigure 4 . Thepermanent magnets 18 are elements which are or can be arranged into a state of persistent magnetization. When thepermanent magnets 18 are arranged into the state of persistent magnetization, they have a magnetic field, and when at least part of the component of therock breaking system 14 is subjected to the effect of the magnetic field of at least onepermanent magnet 18, at least part of the component of therock breaking system 14 is further arranged into a state of persistent magnetization. Further, when stress is acting on the component arranged into the state of persistent magnetization during rock breaking, or in other words, when stress affects the component of the rock breaking system arranged into the state of persistent magnetization, the stress causes a change in a magnetic property of the component. - The component of the
rock breaking system 14, at least part of which may be arranged into the state of persistent magnetization, may for example be theimpact mechanism 5, the frame structure 5' of theimpact mechanism 5, theimpact device 15, thedrill shank 16, the attenuatingdevice 17, thetool 9 of therock breaking system 14 such as thedrill rods drill bit 11. The component of therock breaking system 14, at least part of which may be arranged into the state of persistent magnetization, may also be an adapter or a coupling sleeve in the impact mechanism, for example. The components of therock breaking system 14 which may be arranged into the state of persistent magnetization are thus components which may generate, convey or damp the stresses or the stress waves appearing during rock breaking. - The state of persistent magnetization may be a state of magnetization that remains for a relatively long period of time as in a permanent magnet, a state of magnetization that is maintained by intermittent application of an external magnetic source, a state of magnetization remaining internally in the component material resulting from exposure to an external magnetic field, or a state of persistent magnetization that need not be maintained with an external magnetic source during a measurement period. It is possible that the state of persistent magnetization is provided by a single intermittent application of a magnetic source either by active means, some examples of which are provided later, or by non-active means, such as a permanent magnet. Also arranging a component into a non-magnetic state is in this context considered to correspond to arranging the component into the state of persistent magnetization.
- The change in the magnetic property of the component may be a change in a magnetic field of the component, a change in a magnetic flux of the magnetic field of the component, a change in a permeability or magnetic inductivity of the component or a change in a state or intensity of magnetization of the component, for example. The change in the magnetic property of the component is thus a consequence of a change in the state of the material of the component being subjected to stress. Because the solution deals with the state of persistent magnetization, changes in the magnetic property of the component subjected to stress can be detected more consistently.
- In
Figure 4 thepermanent magnets 18 are fastened in a supportingstructure 19 and have a circular form so that thepermanent magnets 18 may be arranged to surround the component at least part of which will be arranged into a state of persistent magnetization with at least onepermanent magnet 18. InFigure 4 thepermanent magnets 18 are arranged to surround therod 10a of thetool 9, thedrill shank 16, the attenuatingdevice 17 and theimpact device 15. -
Figure 5 discloses schematically some further possible locations where one or morepermanent magnets 18 may be located in therock breaking system 14 ofFigure 3 . InFigure 5 the permanent magnets also have the circular shape but the supportingstructures 19 disclosed inFigure 4 have been left out. In the embodiment ofFigure 5 there arevoids 20 formed in the frame structure 5' of theimpact mechanism 5, thedrill shank 16, the attenuatingdevice 17 and theimpact device 15, whereby thepermanent magnets 18 may be arranged inside said components by arranging thepermanent magnets 18 into thevoids 20 in the components. Also the interior of thedrill rod 10a, for example, forms a kind of void wherein at least onepermanent magnet 18 may be arranged. In thedrill shank 16 thepermanent magnet 18 may be located in a flushingchannel 31 of thedrill shank 16, for example, the flushing channel forming a kind of void in thedrill shank 16. -
Figures 4 and 5 show schematically some possible locations where thepermanent magnets 18 may be arranged in therock breaking system 14. The arrangement may, however, comprise only onepermanent magnet 18 to arrange at least part of one rock breaking system component into the state of persistent magnetization. Alternatively, the arrangement may comprise two or morepermanent magnets 18 to arrange at least part of one or more rock breaking system components into the state of persistent magnetization. Therefore in the arrangement there may be several rock breaking system components each having a relatingpermanent magnet 18 or one or more rock breaking system components having several relatingpermanent magnets 18. Examples of the latter embodiment are also shown schematically inFigures 4 and 5, Figure 4 disclosing two successivepermanent magnets 18 surrounding thedrill shank 16 andFigure 5 disclosing two successivepermanent magnets 18 arranged in the void 20 in the frame structure 5' of theimpact mechanism 5. If in the arrangement there are severalpermanent magnets 18 relating to one rock breaking system component, the permanent magnets may also be arranged to be successive in relation to each other in the circumferential direction of the specific rock breaking system component. In this case the permanent magnets may have a form of a rectangle, for example. - Because in the examples of
Figures 4 and 5 the permanent magnets are arranged permanently in the vicinity of the rock breaking system components, the permanent magnets are thus arranged to continuously provide at least part of the component of the rock breaking system into the state of persistent magnetization in the examples ofFigures 4 and 5 . -
Figures 4 and 5 disclose schematically also means for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the rock breaking system component, the change in the magnetic property of the component originating from the stress, such as the stress wave, affecting the component of therock breaking system 14 during the operation of therock breaking system 14. - In
Figure 4 the measuring member for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component is ameasurement coil 21, which in the embodiment ofFigure 4 is arranged to surround thedrill rod 10a, in the area of thedrill rod 10a arranged into the state of persistent magnetization by thepermanent magnet 18 next to thedrill rod 10a. Themeasurement coil 21 could, however, alternatively be arranged next to some other rock breaking system component in the area of the component arranged into the state of persistent magnetization by thepermanent magnet 18. There could also be more than onemeasurement coil 21 next to either the same or different rock breaking system components for measuring the change in the magnetic property of the specific one or more components. Due to the change in the magnetic property of the component a voltage or current equivalent to the change in the magnetic property of the component is induced in themeasurement coil 21. The induced voltage or current, in turn, indicates the stresses affecting the specific rock breaking system component. - In
Figure 5 the measuring member for measuring the change in the magnetic property of the component is amagnetic sensor 22, which in the embodiment ofFigure 5 is arranged in thedrill shank 16, in the area of thedrill shank 16 arranged into the state of persistent magnetization by thepermanent magnet 18 in thedrill shank 16. Themagnetic sensor 22 could, however, alternatively be in some other rock breaking system component in the area of the component arranged into the state of persistent magnetization. There could also be more than onemagnetic sensor 22 in either the same or different rock breaking system components for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the specific one or more components. Themagnetic sensor 22 may, for example, be a coil, a magnetometer, a magnetoresistive element or a Hall-sensor. - The measurement information provided by the measuring member is transferred, either through a wired connection or a wireless connection, schematically indicated by
arrow 23, to adata processing unit 24. Thedata processing unit 24 comprises software- and/or hardware-based means for processing or modifying the measurement information provided by the measuring member to reach a meaningful representation of the measurement information provided by the measuring member such that the measurement information may be analysed and/or used for controlling the operation of therock breaking system 14 or the wholerock drilling rig 1 or the breaking hammer. The processing or modification methods disclosed inDE19932838 andUS 6,356,077 , for example, may be applied. - When
permanent magnets 18 are used for arranging at least part of the component of the rock breaking system into the state of persistent magnetization, disturbances do not appear in the measurement of the changes in the magnetic property of the rock breaking system component due to the stress acting on the rock breaking system component, which disturbances take place in prior art solutions comprising a magnetizing coil to magnetize the rock breaking system component simultaneously during the measurement of the changes in the magnetic property of the rock breaking system component. - When considering the operation of the arrangement for measuring rock breaking dynamics, instruments relating to the measurement operation, like permanent magnets, are preferably manufactured of electrically non-conductive material. Possible coils, however, are naturally made of electrically conductive material.
-
Figure 6 shows schematically a partly cross-sectional side view of a magnetizing meansstructure 27 intended to arrange at least part of the rock breaking system component into the state of persistent magnetization andFigure 7 shows schematically a partly cross-sectional end view of the magnetizing meansstructure 27 ofFigure 6 . The magnetizing meansstructure 27 comprises a singlepermanent magnet 18, which in the embodiment ofFigures 6 and 7 has a shape of a ring which is arranged to surround the rock breaking system component, i.e. thedrill rod 10a, in the example ofFigures 6 and 7 . Thepermanent magnet 18 is inserted inside the supportingstructure 19 comprising ajacket 25 surrounding thepermanent magnet 18 andend plates 26 so that the supportingstructure 19 is a closed structure enclosing thepermanent magnet 18 inside the supportingstructure 19. For the sake of clarity, the lineation indicating the cross-section of thejacket 25 has not been shown inFigure 7 . At least one of theend plates 26 may be detachable for inserting thepermanent magnet 18 inside the supportingstructure 19. The supportingstructure 19 forms a guiding member for guiding the magnetic field provided by thepermanent magnet 18 to the rock breaking system component for arranging at least part of the rock breaking system component into the state of persistent magnetization by the magnetic field provided by thepermanent magnet 18. - In the embodiment of
Figures 6 and 7 the ring-shapedpermanent magnet 18 is arranged to entirely surround the rock breaking system component, i.e. thedrill rod 10a. Thepermanent magnet 18 surrounding either partly or entirely the rock breaking system component under interest could also have another curvilinear shape. The shape or form of thepermanent magnet 18 surrounding at least partly the rock breaking system component under interest may also have other kind of at least partly circumferential shape than the curvilinear or annular form. - In the embodiment of
Figures 6 and 7 themeasurement sensor 22 is also arranged inside the inner periphery of thepermanent magnet 18. The embodiment ofFigures 6 and 7 thus provides a combination of thepermanent magnet 18, i.e. the element at least part of which is arranged into the state of persistent magnetization, and the measuring member, i.e. themeasurement sensor 22. The ends of the measurement sensor 22 (not shown) may be arranged to run through theend plates 26, for example, if themeasurement sensor 22 has a form of a coil. -
Figure 8 shows schematically a partly cross-sectional end view of a second magnetizing meansstructure 27. For the sake of clarity the lineation indicating the cross-section of thejacket 25 has not been shown inFigure 8 . InFigure 8 , compared toFigure 7 , the ring-shapedpermanent magnet 18 ofFigure 6 is replaced by a number ofpermanent magnets 18 having a shape of a round bar and arranged adjacently to each other in thejacket 25 of the supportingstructure 19 in such a way that that thepermanent magnets 18 are arranged to surround the whole periphery of the rock breaking system component, i.e. thedrill rod 10a, under interest. -
Figure 9 shows schematically a partly cross-sectional end view of a third magnetizing meansstructure 27. For the sake of clarity the lineation indicating the cross-section of thejacket 25 has not been shown inFigure 9 . InFigure 9 , compared toFigure 8 , the ring-shapedpermanent magnets 18 having a shape of a round bar are arranged adjacent to each other in thejacket 25 of the supportingstructure 19 in such a way that thepermanent magnets 18 are arranged to surround only a part of the periphery of the rock breaking system component, i.e. thedrill rod 10a, under interest. - In the embodiments of
Figures 6 to 9 there are a number of permanent magnets, i.e. one or more permanent magnets, arranged to at least partly surround the component of the rock breaking system for arranging at least part of the rock breaking system component into the state of persistent magnetization. In the embodiments ofFigures 8 and 9 the cross-sectional shape of the bar-like permanent magnets may also differ from the round shape. -
Figure 10 shows schematically a partly cross-sectional end view of a fourth magnetizing meansstructure 27. For the sake of clarity the lineation indicating the cross-section of thejacket 25 has not been shown inFigure 10 . The magnetizing meansstructure 27 ofFigure 10 has twoportions 27', 27", each comprising the supportingstructure 19, thepermanent magnet 18 and themeasurement sensor 22 having a shape of semiarch. The twoportions 27', 27" may be combined, for example by using a joint hinge, with each other to form one magnetizing meansstructure 27 having a round form by placing the portions against each other. Themeasurement sensors 22 may also be connected together. For the sake of clarity theportions 27', 27" inFigure 10 are shown to have a small distance between them and no joint hinge is shown inFigure 10 . The magnetizing meansstructure 27 ofFigure 10 may be assembled around the rock breaking system component not only from the end of the component but also from the side of the component. - In the embodiment of
Figure 10 , a group of two permanent magnets is arranged together to form a circumferential structure, which is openable for arranging the group of permanent magnets around the component of the rock breaking system. In the embodiment ofFigure 10 the two permanent magnets form, in practice, a single permanent magnet arranged around the rock breaking system component. Also permanent magnets having a shape or a form differing from the circumferential structure may be arranged in some way openable. Also a measuring member may be arranged openable in a similar way as explained in the specification relating toFigure 10 . When the structure of the magnetization means and/or measuring member is openable, it is openable in a way to enable placement in the vicinity of the rock breaking system or to at least partly surround the rock breaking system. It may also be openable for maintenance and service purposes of the magnet(s), magnetization means, rock breaking system or the rock breaking device, such as a drill rig. - In the embodiments of
Figures 6 to 10 thepermanent magnet 18 orpermanent magnets 18 may be manufactured of electrically conductive material without harmful deteriorating effect to the measurement of rock breaking dynamics if thejacket 25 is made of electrically non-conductive material. - In the examples of
Figures 6 to 10 the magnetization meansstructure 27 provides or forms a measuring instrument for measuring a change in a magnetic property of an object, the measuring instrument comprising at least one magnetization means for arranging at least part of the object into a state of persistent magnetization and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object, the object being thedrill rod 10a in the examples ofFigures 6 to 10 . The measuring instrument thus comprises both at least one magnetization means for arranging at least part of the object into a state of persistent magnetization and at least one measuring member for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object. The magnetization means may be, for example, apermanent magnet 18, as disclosed above, or a magnetizingcoil 28 or a combination of one or morepermanent magnets 18 and the magnetizingcoil 28, as disclosed later. The measuring member may be, for example, ameasurement coil 21 or amagnetic sensor 22, as disclosed above. The structure of the measuring instrument may be openable as disclosed above in the example ofFigure 10 and the relating description, for example. In the examples of this specification the measuring instrument is used for measuring changes in the magnetic property of the component of therock breaking system 14, but generally, the measuring instrument disclosed may also be used for measuring changes in the magnetic property of other objects subjected to stress. - In the examples above, in the arrangement for measuring rock breaking dynamics the element, at least part of which is arranged into the state of persistent magnetization, is thus the permanent magnet, the magnetic field of the permanent magnet, in turn, arranging at least part of the component of the rock breaking system into the state of persistent magnetization. Alternatively, in the arrangement for measuring rock breaking dynamics the element, at least part of which is arranged into the state of persistent magnetization, may also be the component of the rock breaking system, i.e. for example, referring to
Figure 11 , theimpact mechanism 5, theimpact device 15, thedrill shank 16, the attenuatingdevice 17, thetool 9 of therock breaking system 14 such as thedrill rods drill bit 11 and also the frame structure 5' of theimpact mechanism 15, which is not shown inFigure 11 . When at least part of the component of the rock breaking system is arranged into the state of persistent magnetization the component itself is arranged into a state of persistent magnetization, whereby the component itself has a magnetic property, the change of which is measured, for measuring at least one parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component. -
Figure 11 discloses magnetizingcoils 28 used as magnetizing means, which may be used to arrange at least part of the component of therock breaking system 14 into the state of persistent magnetization. In the example ofFigure 11 one or more magnetizing coils 28 are arranged to surround thedrill rod 10a, thedrill shank 16, the attenuatingdevice 17 and theimpact device 15. One or more magnetizing coils 28 may also be arranged to surround the frame structure of theimpact device 5. InFigure 11 thedrill rod 10a, the attenuatingdevice 17 and theimpact device 5 are surrounded by only one magnetizingcoil 28 but they could also be surrounded by two or more magnetizing coils 28. The magnetizing coils 28 could also be inserted in voids provided in the rock breaking system components in a similar way as the permanent magnets in the example ofFigure 5 . The change in the magnetic property of the component of therock breaking system 14 may be measured for example as explained in the examples ofFigures 4 and 5 . - The arrangement in
Figure 11 comprises also a power source 29 configured to provide the necessary electric power for the magnetization coils 28 through the connections presented byarrows 30. The power source 29 is configured to provide an electromagnetic pulse in order to arrange at least part of the component of therock breaking system 14 into the state of persistent magnetization. The length, shape and amplitude of the electromagnetic pulse may be fixed or variable. The component of therock breaking system 14 may be arranged into the state of persistent magnetization at intervals, for example at regular intervals, on the basis of an operating state of therock breaking system 14, on the basis of operation of the measuring member or on the basis of a change in the magnetic property of the component of therock breaking system 14. At least part of the component of therock breaking system 14 may be arranged into the state of persistent magnetization also prior to use of the component in therock breaking system 14. - When the component of the
rock breaking system 14 is arranged into the state of persistent magnetization at intervals, there are certain time periods between which the magnetization operations are provided. The time periods may be related to absolute time, rock breaking time, work shift durations and so on. The interval may also be defined on the basis of rock breaking operations, such as a drilled distance, a number of impacts subjected to thetool 9, an amount of impact energy or energy in general travelled through thetool 9 and so on. An interval may also be used for making magnetization operations occur at least within the interval. That is, if magnetization operations have not taken place during a defined interval, magnetization operations are executed. - When the component of the rock breaking system is arranged into the state of persistent magnetization on the basis of an operating state of the
rock breaking system 14, the magnetization operations may be executed, for example, during an idle state of theimpact device 15, such as between successive impacts, between impact series, upon beginning to drill a hole, during a change of anew drill rod 10a, upon finishing a hole, during positioning the rock breaking system for drilling a hole, during movement of the rock breaking system or device, such as therock drilling rig 1, at the rock breaking site. - When the component of the
rock breaking system 14 is arranged into the state of persistent magnetization on the basis of the operation of the measuring member, the magnetization operations may be executed during an idle state of the measuring member, or, for example when it is observed that quality of measurement suffers from improper state of magnetization. The magnetization operations may also be executed on the basis of a measured value or measurement result. The measured value or measurement result may be obtained from an additional sensor, possibly external to the rock breaking system or the measurement system. - When the component of the
rock breaking system 14 is arranged into the state of persistent magnetization on the basis of a change in the magnetic property of the component of the rock breaking system, the magnetization operations may be executed when it is observed that the state of persistent magnetization has changed to such an extent that no reliable measurement information cannot be obtained. - When the component of the rock breaking system is arranged into the state of persistent magnetization prior to use of the component in the rock breaking system, at least part of the component may be arranged into the state of persistent magnetization for example after the manufacturing of the component, before assembling the component to the rock breaking system either at the factory or use site of the rock breaking system, or after assembling the component to the rock breaking system but before the actual operation of the rock breaking system. At least part of the component of the rock breaking system may thus be arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system.
- The operation of the magnetization may be controlled for example with the
data processing unit 24. - In the example of
Figure 11 and the related specification above, the component of the rock breaking system is arranged into the state of persistent magnetization by using only themagnetization coil 28 as the magnetization means. It is however possible that a permanent magnet is arranged in combination with themagnetization coil 28. It is also possible that instead of using themagnetization coil 28 only a permanent magnet is used for arranging the specific component of the rock breaking system into the state of persistent magnetization by arranging the permanent magnet in the vicinity of the specific rock breaking system component only for a specific time period as explained above. Thus also only the permanent magnet may be used to intermittently provide at least part of the component of the rock breaking system into the state of persistent magnetization. - When at least part of the component of the rock breaking system is arranged into the state of persistent magnetization, which state of persistent magnetization may be stimulated if necessary, the component of the rock breaking system itself provides the magnetic property which is observed when the parameter of rock breaking dynamics is measured on the basis of the change in the magnetic property of the component. In this case, disturbances do not appear either in the measurement of the changes in the magnetic property of the rock breaking system component due to the stress acting on the rock breaking system component, which disturbances take place in prior art solutions comprising a magnetizing coil to magnetize the rock breaking system component simultaneously during the measurement of the changes in the magnetic property of the rock breaking system component.
- According to an embodiment, the
magnetization coil 28 may be used as a measurement coil too. In this embodiment themagnetization coil 28 may be used both for providing the electromagnetic pulse for arranging a component of the rock breaking system into the state of persistent magnetization and for providing a measurement of a parameter of rock breaking dynamics on the basis of the change in the magnetic property of the component after the component has been arranged into the state of persistent magnetization, i.e. at the time themagnetization coil 28 is not used for arranging the component of the rock breaking system into the state of persistent magnetization. -
Figures 12 and 13 show schematically an example of a measurement result of a stress wave,Figure 13 being more detailed presentation of the first part of the measurements ofFigure 12 . InFigures 12 and 13 the dashed line represents the stress wave measured by a strain gauge attached to a rock breaking system component. The continuous line, in turn, represents the same stress wave measured by a measurement coil when permanent magnets were used for arranging the same rock breaking system component into the state of persistent magnetization. FromFigures 12 and 13 it can be seen that the stress wave measurement provided by the presented solution corresponds to the measurement provided by the strain gauge, which can be considered to follow exactly the stress wave appearing in the rock breaking system component, because the strain gauge is directly fixed to the rock breaking system component. - Examples of the measurement arrangement disclosed above relate to the measurement of stresses or stress waves affecting the rock breaking system during rock breaking, but the measurement arrangement may also be utilized in other ways for measurement of rock breaking dynamics or related parameters. The measurement arrangement may also be utilized in the determination of other phenomena or events, such as determination of the impact frequency or characteristics of the broken rock, as well as in the condition monitoring of the rock breaking system or its components.
- It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
Claims (15)
- An arrangement for measuring rock breaking dynamics, the arrangement comprising
at least one component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of a rock breaking system (14), the component being subjected to stress during rock breaking,
at least one element (5, 5', 9, 10a, 10b, 10c, 15, 16, 17, 18), at least part of which is arranged into a state of persistent magnetization, and
at least one measuring member (21, 22) for measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component. - An arrangement as claimed in claim 1, wherein at least part of the element (5, 5', 9, 10a, 10b, 10c, 15, 16, 17, 18) is arranged into the state of persistent magnetization with a magnetic field external to the rock breaking system (14).
- An arrangement as claimed in claim 1 or 2, wherein the element is a permanent magnet (18) arranged to provide at least part of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) into the state of persistent magnetization.
- An arrangement as claimed in claim 3, wherein the arrangement comprises a number of permanent magnets (18) arranged to at least partly surround the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14).
- An arrangement as claimed in claim 1 or 2, wherein the element, at least part of which is arranged into the state of persistent magnetization, is the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14).
- An arrangement as claimed in claim 5, wherein the arrangement comprises magnetization means (18, 28) for arranging at least part of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) into the state of persistent magnetization.
- An arrangement as claimed in claim 6, wherein the magnetization means (28) is configured to provide an electromagnetic pulse for arranging at least part of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) into the state of persistent magnetization.
- An arrangement as claimed in claim 6 or 7, wherein the magnetization means (18, 28) is configured to arrange at least part of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) into the state of persistent magnetization at intervals.
- An arrangement as claimed in any one of claims 5 to 8, wherein at least part of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) is arranged into the state of persistent magnetization prior to use of the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) in the rock breaking system (14).
- An arrangement as claimed in claim 3, 4, 6, 7, 8 or 9, wherein the rock breaking system (14) comprises at least one void (20) into which at least one permanent magnet (18) or magnetization means (18, 28) is arranged.
- An arrangement as claimed in claim 3, 4, 6, 7, 8, 9 or 10, wherein a single permanent magnet (18), a group of permanent magnets (18) or the magnetization means (18, 28) is arranged to provide at least partly circumferential structure.
- An arrangement as claimed in claim 3, 4, 6, 7, 8, 9, 10 or 11, wherein a single permanent magnet (18), a group of permanent magnets (18) or the magnetization means (18, 28) is openable.
- An arrangement as claimed in any one of the preceding claims, wherein the component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of the rock breaking system (14) is one of a tool (9), a drill rod (10a, 10b, 10c), a drill bit (11), a component of an impact mechanism (5) such as a frame structure (5') of the impact mechanism (5), impact device (15), a drill shank (16), an attenuating device (17), an adapter and a coupling sleeve.
- A method for measuring rock breaking dynamics, the method comprising
arranging at least part of a component (5, 5', 9, 10a, 10b, 10c, 15, 16, 17) of a rock breaking system (14) into a state of persistent magnetization, the component being subjected to stress during rock breaking, and
measuring at least one parameter of rock breaking dynamics on the basis of a change in a magnetic property of the component. - A measuring instrument comprising
at least one magnetization means (18, 28) for arranging at least part of an object into a state of persistent magnetization, and
at least one measuring member (21, 22) for measuring at least one parameter describing a change in the magnetic property of the object in response to stress exerted on the object.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP13171043.6A EP2811110B1 (en) | 2013-06-07 | 2013-06-07 | Arrangement and Method in Rock Breaking |
AU2014202974A AU2014202974B2 (en) | 2013-06-07 | 2014-06-02 | Arrangement and method in rock breaking |
JP2014117892A JP5767368B2 (en) | 2013-06-07 | 2014-06-06 | Rock crushing apparatus and method |
CN201410250032.7A CN104236762A (en) | 2013-06-07 | 2014-06-06 | Arrangement and method in rock breaking |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP13171043.6A EP2811110B1 (en) | 2013-06-07 | 2013-06-07 | Arrangement and Method in Rock Breaking |
Publications (2)
Publication Number | Publication Date |
---|---|
EP2811110A1 true EP2811110A1 (en) | 2014-12-10 |
EP2811110B1 EP2811110B1 (en) | 2017-09-20 |
Family
ID=48578853
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP13171043.6A Active EP2811110B1 (en) | 2013-06-07 | 2013-06-07 | Arrangement and Method in Rock Breaking |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP2811110B1 (en) |
JP (1) | JP5767368B2 (en) |
CN (1) | CN104236762A (en) |
AU (1) | AU2014202974B2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2017217905A1 (en) * | 2016-06-17 | 2017-12-21 | Atlas Copco Rock Drills Ab | System and method for assessing the efficiency of a drilling process |
EP3266975A1 (en) | 2016-07-07 | 2018-01-10 | Sandvik Mining and Construction Oy | Component for rock breaking system |
WO2022139654A1 (en) | 2020-12-21 | 2022-06-30 | Epiroc Rock Drills Aktiebolag | Method and system for optimising a drilling parameter during an ongoing drilling process |
WO2022139655A1 (en) | 2020-12-21 | 2022-06-30 | Epiroc Rock Drills Aktiebolag | Method and system for detecting a state of a joint of a drill string |
EP4276438A1 (en) * | 2022-05-13 | 2023-11-15 | Sandvik Mining and Construction Oy | Measuring rock breaking dynamics |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109113742B (en) * | 2018-08-02 | 2019-12-31 | 中国矿业大学 | Coal reservoir stratum present ground stress prediction method |
CN112403563A (en) * | 2020-10-30 | 2021-02-26 | 重庆贻晨兴工业设计有限责任公司 | Double-channel jaw crusher and using method thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4671366A (en) | 1984-06-12 | 1987-06-09 | Oy Tampella Ab | Method for optimizing rock drilling |
DE19932838A1 (en) | 1999-07-14 | 2001-01-18 | Hilti Ag | Method and device for determining the time course of the shock wave in a shock-stressed ferromagnetic component |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6190037A (en) * | 1984-10-09 | 1986-05-08 | Takenaka Komuten Co Ltd | Method and device for measuring compressive strength of concrete |
JPH01193180A (en) * | 1988-01-26 | 1989-08-03 | Mazda Motor Corp | Over-load detection method for striking tool |
JPH055603A (en) * | 1991-06-27 | 1993-01-14 | Mazda Motor Corp | Stroke detector of piston |
JP4217321B2 (en) * | 1997-12-26 | 2009-01-28 | ヤマハ発動機株式会社 | Load detection device |
DE10219950C1 (en) * | 2002-05-03 | 2003-10-30 | Hilti Ag | Pneumatic hammer mechanism with magnetic field sensitive sensor |
FI122300B (en) * | 2008-09-30 | 2011-11-30 | Sandvik Mining & Constr Oy | Method and arrangement for a rock drilling machine |
-
2013
- 2013-06-07 EP EP13171043.6A patent/EP2811110B1/en active Active
-
2014
- 2014-06-02 AU AU2014202974A patent/AU2014202974B2/en active Active
- 2014-06-06 JP JP2014117892A patent/JP5767368B2/en active Active
- 2014-06-06 CN CN201410250032.7A patent/CN104236762A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4671366A (en) | 1984-06-12 | 1987-06-09 | Oy Tampella Ab | Method for optimizing rock drilling |
DE19932838A1 (en) | 1999-07-14 | 2001-01-18 | Hilti Ag | Method and device for determining the time course of the shock wave in a shock-stressed ferromagnetic component |
US6356077B1 (en) | 1999-07-14 | 2002-03-12 | Hilti Aktiengesellschaft | Method of and device for determining a time-dependent gradient of a shock wave in a ferromagnetic element subjected to a percussion load |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3472427B1 (en) | 2016-06-17 | 2021-10-27 | Epiroc Rock Drills Aktiebolag | System and method for assessing the efficiency of a drilling process |
AU2017285884B2 (en) * | 2016-06-17 | 2022-06-09 | Epiroc Rock Drills Aktiebolag | System and method for assessing the efficiency of a drilling process |
CN109312617A (en) * | 2016-06-17 | 2019-02-05 | 安百拓凿岩有限公司 | System and method for assessing the efficiency of drilling process |
EP3472427A1 (en) * | 2016-06-17 | 2019-04-24 | Epiroc Rock Drills Aktiebolag | System and method for assessing the efficiency of a drilling process |
US11459872B2 (en) | 2016-06-17 | 2022-10-04 | Epiroc Rock Drills Aktiebolag | System and method for assessing the efficiency of a drilling process |
EP3472427A4 (en) * | 2016-06-17 | 2020-02-19 | Epiroc Rock Drills Aktiebolag | System and method for assessing the efficiency of a drilling process |
CN109312617B (en) * | 2016-06-17 | 2022-05-27 | 安百拓凿岩有限公司 | System and method for evaluating efficiency of a drilling process |
WO2017217905A1 (en) * | 2016-06-17 | 2017-12-21 | Atlas Copco Rock Drills Ab | System and method for assessing the efficiency of a drilling process |
EP3266975A1 (en) | 2016-07-07 | 2018-01-10 | Sandvik Mining and Construction Oy | Component for rock breaking system |
US10550685B2 (en) | 2016-07-07 | 2020-02-04 | Sandvik Mining and Constuction Oy | Component for rock breaking system |
WO2022139655A1 (en) | 2020-12-21 | 2022-06-30 | Epiroc Rock Drills Aktiebolag | Method and system for detecting a state of a joint of a drill string |
WO2022139654A1 (en) | 2020-12-21 | 2022-06-30 | Epiroc Rock Drills Aktiebolag | Method and system for optimising a drilling parameter during an ongoing drilling process |
EP4276438A1 (en) * | 2022-05-13 | 2023-11-15 | Sandvik Mining and Construction Oy | Measuring rock breaking dynamics |
WO2023218013A1 (en) * | 2022-05-13 | 2023-11-16 | Sandvik Mining And Construction Oy | Measuring rock breaking dynamics |
Also Published As
Publication number | Publication date |
---|---|
CN104236762A (en) | 2014-12-24 |
JP5767368B2 (en) | 2015-08-19 |
EP2811110B1 (en) | 2017-09-20 |
AU2014202974B2 (en) | 2016-06-23 |
AU2014202974A1 (en) | 2015-01-15 |
JP2014237217A (en) | 2014-12-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2811110B1 (en) | Arrangement and Method in Rock Breaking | |
US6367565B1 (en) | Means for detecting subterranean formations and monitoring the operation of a down-hole fluid driven percussive piston | |
CN102164714B (en) | Method and arrangement in rock drilling rig | |
NO339498B1 (en) | Method and apparatus for generating acoustic signals for measuring shear wave velocity during logging during drilling | |
CN109312617B (en) | System and method for evaluating efficiency of a drilling process | |
EP3617441B1 (en) | Rock breaking device | |
US7990138B2 (en) | Probe for analysis of a string of rods or tubes in a well | |
CA2970269C (en) | Component for rock breaking system | |
WO2023218013A1 (en) | Measuring rock breaking dynamics | |
CA2851922A1 (en) | Arrangement and method in rock breaking | |
JP2017125684A (en) | Geological survey method in front of working face | |
RU2613381C1 (en) | Method for determining boundaries of water-cement between pipes in hydrocarbon well | |
KR101638158B1 (en) | Device for prediction underground dynamic behavior of mines by using acoustic emission sensor | |
US9151151B2 (en) | Method for localizing a drilling device of an earth drilling apparatus | |
EP2971460B1 (en) | Well tool for use in a well pipe | |
JPH03504775A (en) | Method for measuring the inclination of the wall of a slotted hole | |
RU93880U1 (en) | DEVICE FOR DETERMINING THE TECHNICAL CONDITION OF THE CASING | |
PL112262B1 (en) | Device for measurement of tool impact force and frequency in a machine particularly in a mining hammer drill ordrifter drill |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20130607 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
R17P | Request for examination filed (corrected) |
Effective date: 20150610 |
|
RBV | Designated contracting states (corrected) |
Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
17Q | First examination report despatched |
Effective date: 20160223 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
INTG | Intention to grant announced |
Effective date: 20170622 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 930292 Country of ref document: AT Kind code of ref document: T Effective date: 20171015 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602013026785 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: TRGR |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20171220 |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG4D |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK05 Ref document number: 930292 Country of ref document: AT Kind code of ref document: T Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20171220 Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20171221 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: CZ Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 6 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20180120 Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 602013026785 Country of ref document: DE |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
26N | No opposition filed |
Effective date: 20180621 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20180607 |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20180630 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180607 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180607 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180630 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180630 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180630 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20180607 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20130607 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20170920 Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20170920 |
|
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20230603 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20230523 Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20230510 Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IE Payment date: 20240509 Year of fee payment: 12 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20240502 Year of fee payment: 12 |