CN101449021A - A top hammer rock-drilling tool, a drill rod and coupling sleeve - Google Patents

Abstract

In a first aspect, the invention relates to a rock-drilling tool that comprises a drill rod (1) having a male thread (5) as well as a coupling sleeve having a female thread for the co-operation with the male thread of the drill rod. The male thread (5) of the drill rod may consist of a martensitic stainless steel. Axially inside the male thread (5), a waist (32) is formed in which the drill rod (1) has the smallest diameter thereof. Furthermore, an external, cylindrical guide surface (31) is positioned between the male thread (5) and the waist (32) and has the purpose of co-operating with an internal guide surface positioned between the female thread and a free end of the coupling sleeve. Furthermore, the invention relates to a drill rod as such as well as a coupling sleeve as such.

Description

Top hammer rock-drilling tool, drilling rod and joint sheeve

Technical field

In first aspect, the present invention relates to top hammer rock-drilling tool, the rock-drilling tool of the type comprises drilling rod with pin thread and has the joint sheeve that is used for the negative thread of cooperating with the pin thread of drilling rod.

In other respects, the invention still further relates to drilling rod and the joint sheeve that is used for this rock-drilling tool.

Background technology

The equipment that is used for many types of actual brill rock comprises: on the one hand, have the stationary placed machine of handle adapter, in addition on the one hand, with drill bit, at least one drilling rod and the drill tools that is used for drilling rod and the form of the joint sheeve that is connected of handle adapter.In addition, the drilling rod that is connected to the handle adapter can be connected with one or more addition rods and be formed for boring the longer drill string in darker hole.In top hammer, the handle adapter is set to the combination of impacting and rotatablely moving is provided, and the combination of this motion passes to drill bit by drilling rod or drill string.

In general rockhole equipment and at the equipment that specifically is used for top hammer, technology and economic characteristic there is very high requirement.At technical elements, drill tools should be able to be not only soon but also get out in the rock of various character efficiently may the most straight hole.User's economic interests are not only the technical performance of the drill tools of coming of new, and still are the application life of this drill tools to a great extent.This depends on many different factors, and one of them factor is the ability of boring corrosion fatigue resistant.This corrosion fatigue that can cause the fracture of drilling rod appear at drilling rod will impact and rotatablely move pass to drill bit duration of work when drilling rod is subjected to corrosive attack, initial crack, this corrosive attack is with relevant with the fluctuating load of shock wave and bending motion form, and this initial crack little by little increases and causes fatigue at last.To the formation of crackle responsive especially be thread-groove bottom in the pin thread of drilling rod, drilling rod has little cross-sectional area at this root.Another one determines that the factor in application life is that screw thread inevitably weares and teares, these wearing and tearing appear at when the tooth side of this screw thread because repeat off and on, the power of axial impact and relative spinning movement and when wearing and tearing toward each other, when moment of torsion transmitted between joint sheeve and drilling rod, rotatablely moving that this is relative worked consistently.Therefore, compare with the threads engage of tightening hardy of traditional type, rock bores the serious threads engage that exposes and depends on the fact that the moment of torsion transmission between joint sheeve and the drilling rod provides pin thread " consistently " to screw in negative thread, the tooth side of this screw thread of tightening this joint of causing at first wearing and tearing.If the pin thread of drilling rod is gone bad soon than the negative thread wearing and tearing of joint sheeve, this thread abrasion just becomes bad especially at economic aspect so, and this is because this need change expensive drilling rod before necessity is changed more cheap joint sheeve.For the application life of boring with and the important factor of another one of technical performance be the ability that threads engage is offset deflection, promptly drilling rod with the trend of angled ground of joint sheeve deflection or upset.Ideally, drilling rod and joint sheeve should extend along common central axis (in the scope of handle adapter), become straight ideally so that guarantee the hole of being bored.Screw thread wear and tear manyly, then rigidity reduces manyly more, and the gap in the joint between joint sheeve and drilling rod increases, skewness propagates into threads engage place and accelerated wear test.

US 6196598 (SE 521790) has observed the too early wear problems of the pin thread of the threads engage between drilling rod and the joint sheeve, this problem arrives by the following fact is observed or rather, and it is bigger by 5% to 25% than the wear volume of negative thread to be about to the wear volume (proportional with cross-sectional area) that pin thread is designed to have.With such method, having guaranteed did not need to abandon and change relatively more expensive drilling rod before the negative thread wearing and tearing badly of more cheap joint sheeve.Yet this measure had not both solved the problem of corrosion fatigue, did not have to solve gap and the deflection problem that increases continuously yet.

Summary of the invention

The above-mentioned shortcoming of the rock-drilling tool that the objective of the invention is to avoid known, and a kind of improved instrument is provided.Therefore, primary and foremost purpose of the present invention provides the rock-drilling tool that is suitable for actual top hammer, this rock-drilling tool has optimum performance aspect technical performance and the economic attractiveness, especially can provide long life and continuous and reliable serviceability during its whole Acceptable life.Therefore, the user should look to drilling rod to continue the same for a long time with joint sheeve at least, on the one hand, the trend of the effectively also long-term opposing corrosion fatigue of this drilling rod, on the other hand, this drilling rod is resisted effectively and for a long time and occur the skewness that thread pitch increases inevitably during reality is bored the rock of different structures.The another one purpose just provides simple in structure and therefore makes rock-drilling tool cheap and easy to use.

According to the present invention, utilize the characteristic that characteristic limited of claim 1 to obtain main at least purpose by rock-drilling tool according to the present invention.The preferred embodiment of rock-drilling tool further limits in dependent claims 2-5.

In addition, the present invention relates to drilling rod and joint sheeve itself.See independent claims 6 according to the characteristic of boring of the present invention, and in independent claims 9, limit according to the characteristic of joint sheeve of the present invention.

Further specifying of prior art

By US 6,547,891, previously known the purpose drilling rod that is used for top hammer equipment have the pin thread of making by erosion-resisting martensite steel.In this case, except using concrete material, the disclosure does not comprise anyly how being optimized so that the information of gapless threads engage is provided relevant for the aspect of performance of drilling rod at pin thread.

The threads engage that is used for dissimilar rock-drilling tools is further disclosed in SE 9904324-2, SE 0103407-3 and SE 0201989-1.

Description of drawings

And then the present invention is described below with reference to the accompanying drawings.Because adapter that the end in the end of the drilling rod of this instrument is connected to and the drill bit that is connected to the drilling rod opposite end are all without any direct importance, therefore, these the same with suitable rig in this accompanying drawing parts are not illustrated.

Therefore, in the accompanying drawings:

Fig. 1 is the lateral view according to drilling rod of the present invention,

Fig. 2 is the amplification longitudinal section that is used for the joint sheeve of cooperating with drilling rod according to of the present invention,

Fig. 3 shows the zoomed-in view of the drilling rod end of cooperating with joint sheeve,

Fig. 4 is the cross-sectional view of drilling rod, and

Fig. 5 is that the extreme that shows the design at drilling rod in Fig. 2 and 3 and the threads engage place between the joint sheeve is respectively amplified detailed view.

The specific embodiment

Drilling rod by 1 expression comprises such as the end face by the represented relative two ends 2,3 of plan view, circle in the text, and the length of this drilling rod is the manyfold of its diameter.In practice, bar 1 can have the length of 4-6m and the maximum gauge of about 38mm.End 2 is commonly referred to pommel, and this is because this end should always be faced the handle adapter.In the main cross section S that extends along the major part of total length, bar has traditional hexagonal transverse cross section shape (see figure 4), and center irrigating catheter 4 runs through extension end-to-endly.2,3 a distance at the distance two ends, the hexagonal transverse cross section shape stops and converts rotational symmetric substantially surface to, forms external screw thread in this surface, i.e. pin thread.More properly, first pin thread 5 that is provided with is near end 2, and second pin thread 6 that is provided with is near end 3, and second pin thread 6 described later is used for the negative thread in the precession drill bit, or the another one joint sheeve of precession traditional type (not shown), screw thread 6 is less important.

In this case, joint sheeve is columniform on 7 surfaces, and comprises two cavitys 8,9, and these two cavitys 8,9 are separated wall 10 to be separated, and at the opposite end of sleeve 11,12 openings.Partition wall 10 has axial width L5.Each independent cavity 8,9 is by cylindrical wall or cover 13,14 and define.Portion forms negative thread 15,16 within it, a negative thread of at first mentioning is used for cooperating with the pin thread 5 on bar 1, a negative thread of then mentioning is used for cooperating with the pin thread on the socket in being included in handle adapter (not shown), its objective is the driving drilling tool.Two cavitys 8,9 communicate with each other by centre bore 17, and this centre bore 17 extends through partition wall 10.

When the negative thread 15 of the pin thread 5 of bar and sleeve was cooperated during operation, end face 2 bottoms were against the surface 18 of partition wall 10.Similarly, the bottom (not shown) of adaptor spigot end is against the opposing flat surfaces 19 of partition wall 10.

According to the present invention, the pin thread on drilling rod 15 can be by the martensitic stain less steel manufacturing at least.If like this, most convenient be the whole of drilling rod by this material manufacturing, two pin threads the 5, the 6th, the integral part of the body of rod.This steel is US 6 547 891 disclosed types advantageously, promptly have the chromium (Cr) of the weight that mainly comprises martensite and comprise at least 10% respectively and the structure of little a spot of carbon (C) and nitrogen (N).This steel can also comprise molybdenum (Mo), tungsten carbide (WC) and the copper (Cu) of different amounts.Martensitic content should reach weight at least 50%, reach at least 75% of weight suitably.

When making the drilling rod of corrosion resistant alloy, owing to add the result of chromium, obtain the passivated surface layer, this layer at first hindered corrosion effectively in the bottom of thread groove.Therefore, with traditional steel comparison, in the thread-groove bottom of sensitivity, rate of corrosion reduces considerably.Therefore, the test of having implemented shows and has improved at least 50% (the rice number that is bored is from about 2000 meters to about 3000 meters) application life.

Therefore stainless steel material is irrefutable to the positive influences in the application life of drilling rod.Yet the corrosive nature that obtains to want is that the wear resistence with material is a cost.Therefore, the about 50HRC of the hardness of the martensite steel of bar, and the case hardness that has with traditional bar material of the form of hardened steel is in the scope of 57-62HRC.

Advantageously, the material of sleeve 7 can be a hardened low-alloy steel, for example, case-hardened steel or carburizing steel, this be because the corrosion fatigue problem of sleeve not resemble this fatigue problem of thread-groove bottom of drilling rod so serious.

Referring now to Fig. 5,, shows two helical thread tooth 5A, 15A that form pin thread and negative thread respectively with the ratio of amplifying among the figure.Male thread ridge 5A has by crest 20 and two contour shapes that tooth side 21,22 limits, and this ridge 5A defines the teething end or groove 23, and this groove has bottom 24, and extends along bar spirality ground as suitable tooth.In this case, contour shape is symmetrical, and this is to tilt with same big angle because the fact is a tooth side 21,22.In this example, ridge crest 20 has the shape that width is the helical surface of B1, this width B 1 has determined the cross-sectional area of ridge 5A, the cross-sectional area of the ridge 5A of pin thread 5 is from the tangent line T2 calculating of the crest 20 of negative thread 15, and the cross-sectional area of the ridge 15A of negative thread 15 is from the tangent line T1 calculating of the crest 25 of pin thread 5, and all cross-sectional areas as described are represented by the shadow region of Fig. 5.In addition, the trench bottom 24 of pin thread has the shape of cross section of level and smooth circle, and this shape of cross section is limited by camber line substantially.The cross-sectional area of ridge 5A is greater than the imaginary cross-sectional area of groove 23.The imaginary cross-sectional area of groove 23 is limited by the area between tangent line T1, bottom 24 and tooth side 21 and 22.

Similarly, as male thread ridge 5A, female thread ridge 15A is limited by crest 25 and two tooth sides 26,27, defines the spiral slot 28 with bottom 29 between this ridge.In this example, trench bottom 29 is limited by straight bus.The width B 2 of the crest 25 of female thread ridge can be less than the width B 1 of crest faces 20.The cross-sectional area that this means female thread ridge 15A can be less than the cross-sectional area of male thread ridge, and the wear volume of understanding male thread ridge in view of the above can be greater than the wear volume of female thread ridge.In this example, the wear volume of female thread ridge 15A reach male thread ridge wear volume about 81.8%.In other words, the wear volume of male thread ridge is greater than the wear volume of female thread ridge about 22%.Yet the ratio between the corresponding wear volume can change considerably, depends on the selection of the material of bar and joint sheeve especially respectively.More properly, the difference of the wear resistance/surface hardness there between the stainless steel of pin thread and the hardened steel of joint sheeve is big more, and then male thread ridge 5A can have big more pro rata wear volume.Therefore, in practice, the wear volume that male thread ridge can have surpasses 20% or 25% greater than the wear volume of female thread ridge, for example 50-75%.

In Fig. 3, A, B, C, D and E refer to many axially crossing plane at interval, and this crossing plane is extended perpendicular to the central axis C L of bar, and between this crossing plane, bar 1 has the longitudinal cross-section of different qualities.Between plane A and B, pin thread 5 extends with full thread (except the taper near end face 2 enters surface 37).The external diameter of ridge (calculating along thread crest 20) is represented by D1, and D2 represents the interior diameter of trench bottom 24.Between plane B and C, extending the enveloping surface 30 of substantially cylindrical, thread groove 23 terminates in this enveloping surface.Enveloping surface 30 can advantageously have the diameter identical with the external diameter D1 of screw thread 5.In addition, between plane C and D, define rotatably symmetry, columniform guide face 31 or rather, the diameter D3 that this guide face has is greater than the diameter of enveloping surface 30, therefore also greater than the external diameter D1 of screw thread.Described guide face 31 is formed at pin thread and tapered waist or shrinks between 32, this tapered waist or shrink 32 and extend between crossing plane D and E.Big half place between crossing plane D and E, waist 32 has minimum diameter D4, and advantageously the interior diameter D2 with pin thread 5 is the same big at the most for this diameter D4.Suitably, the minimum diameter D4 of waist 32 even a bit less than the diameter D2 of thread-groove bottom.Waist 32 is transformed into guide face 31 and hexagonal main section 3 respectively by the transitional surface 33,34 of the continuous expansion of recessed arch.Selectively, this hexagonal main section can be a circular cross-section.

Hexagon shown in Fig. 4 forms the main cross section S of drilling rod, and has the cross-sectional area by the decision of the width dimensions H between the opposing flat surfaces on two diametric(al)s.Interior diameter by the represented irrigating catheter 4 of D5 is significantly less than size H.

L1, L2, L3 and L4 represent the axial length in different bars cross section.In Fig. 3, see the length L 2 of the length L 1 of screw thread 5 greater than enveloping surface 30, the length L 2 of enveloping surface 30 is again greater than the length L 3 of guide face 31.But, guide face 31 has limited length L3.Or rather, guide face 31 can be significantly shorter than or be thinner than enveloping surface 30, and wherein thread groove terminates in the enveloping surface 30.The diameter D3 that the guide face 31 of drilling rod 1 has is that the twice of its axial length L 3 is big at least.The length L 4 of waist 32 can advantageously only be slightly less than the length L 1 of the screw thread of full-sized.

In a specific embodiment, the length L 1 of pin thread 5 is that 75mm, external diameter D1 are 38.7mm and the interior diameter D2 of thread groove root reaches 34mm.This means that the height that male thread ridge has approximately is 2.3mm.The length L 2 that enveloping surface 30 has can be that 17mm, diameter can be 38.7mm, promptly identical with the external diameter D1 of screw thread diameter.Yet the diameter D3 that guide face 31 has reaches 39.1mm greater than diameter D1 in this instantiation.In other words, the diameter difference between guide face 31 and the enveloping surface 30 reaches 0.4mm.The extending axially L3 and then can be restricted to 7mm of guide face 31.In this example, the diameter D4 of the minimum of waist 32 reaches 32.9mm.In other words, in this case, diameter D4 is than the little about 1.1mm of diameter D2 of thread-groove bottom.The axial length L 4 of waist reaches about 57mm.

Joint sheeve 7 (see figure 2)s can be formed with the interior guide face 35 between the free end 11 of negative thread 15 and this sleeve, are used for cooperating with the outer guide face 31 of drilling rod.Described guide face 35 also be rotatably symmetry, be preferably columniformly, have diameter D6, this diameter D6 is only less times greater than the diameter D3 of guide face 31.The axial length L 6 that guide face 35 has is greater than the thickness L5 of partition wall 10.In this specific embodiment example, D6 reaches 39.2mm, this means that the slit between the face 31,35 only reaches 0.05mm.In other words, the cooperation between the guide face 31,35 is good.

Between the end face 11 of guide face 35 and sleeve, be formed with chamfering 36, so that drilling rod is inserted in the sleeve.

In the negative thread 15 of the precession sleeve that the pin thread 5 of drilling rod engages fully, when end face 2 presses against wall 18, guide face 31 next-door neighbour's chamferings 36 location.In other words, in this state, guide face 31 is axially separated with the partition wall 10 maximum ground of joint sheeve.This means that the drilling rod guide face 31,35 that the possible trend of deflection or upset is cooperated in sleeve offsets effectively.

By the following fact, the waist 32 that promptly axially is arranged on the inside of pin thread 5 has the diameter that dwindles, and compares than the thick hexagonal main section S of waist and near the different cross section of rod end, obtains pliability or elastic compliant degree.The deflection trend that this means the drilling rod that occurs inevitably during actual creeping into is absorbed by resilient waist, rather than propagates into the threads engage place between drilling rod and the sleeve.

Basic advantage according to the drill tools that is made of drilling rod, joint sheeve and drill bit (not shown) of the present invention is: it is having optimum performance aspect application life and the technical performance.Therefore, the combination of two between elastic waist and this elastic waist and threads engage cooperation guide face provides the deflection motion of drilling rod to be absorbed rather than to propagate into effect in the suitable threads engage in this waist.The wearing and tearing that this means threads engage are restricted to inevitably wearing and tearing itself, and these wearing and tearing are owing to occur by impact of handle adapter passes and the result that rotatablely moves, but this does not worsen or quickens skewness.According to additional aspects of the present invention, fretting fatigue has wherein been offset in the use of the martensitic stain less steel in the pin thread of drilling rod to a great extent, simultaneously, has guaranteed that expensive drilling rod obtains the same at least long application life with more cheap joint sheeve.

Though the rock-drilling tool purpose of combination of the present invention already described above is used for the boring of posture rock borer and includes only a drilling rod and a joint sheeve, the present invention also is applicable to the rock-drilling tool with two or more bars and joint sheeve respectively.

The application requires the priority of disclosed content among Swedish patent application 0601117-5 and the 0601119-1, and here by reference in conjunction with the content of above-mentioned application.

The present invention is not limited to the above embodiments fully, but can freely change in the restriction of appended claim.

Claims (10)

1. top hammer rock-drilling tool, this rock-drilling tool comprises the have pin thread drilling rod (1) of (5), with have the joint sheeve (7) that is used for the negative thread (15) of cooperating with the pin thread of described drilling rod, it is characterized in that, the pin thread (5) of described drilling rod (1) can be made of martensitic stain less steel, inner shaft at described pin thread (5) forms waist (32) to ground, in described waist, described drilling rod (1) has its minimum diameter, columniform outer guide face (31) is positioned between described pin thread (5) and the described waist (32), purpose be with described negative thread (15) that is positioned described joint sheeve (7) and free end (11) between interior guide face (35) cooperate.

2. rock-drilling tool according to claim 1, it is characterized in that, outside described drilling rod (1) described, form enveloping surface (30) between guide face (31) and the described pin thread (5), the diameter of described enveloping surface (30) is less than the diameter of described outer guide face (31), and the groove (23) of described pin thread (5) terminates in the described enveloping surface.

3. rock-drilling tool according to claim 1 and 2, it is characterized in that the waist (32) of described drilling rod (1) converts the described outer guide face (31) of described drilling rod and the hexagonal section (S) or the circular cross-section of cross section mode to by the transitional surface (33,34) of the continuous expansion of recessed arch.

4. any one the described rock-drilling tool in requiring according to aforesaid right, it is characterized in that, the outer guide face (31) of described drilling rod (1) and the axial distance between its end face (2) are only slightly less than the free end (11) of described joint sheeve (7) and the distance between the interior partition wall (10), and the free end of wherein said drilling rod (2) can be pressed against described interior partition wall (10).

5. any one the described rock-drilling tool in requiring according to aforesaid right, it is characterized in that, the diameter (D3) that the outer guide face (31) of described drilling rod (1) has is that the twice of its axial length (L3) is big at least, and the wear volume that described pin thread (5) has is greater than the wear volume of described negative thread (15).

6. top hammer drilling rod that is used for rock-drilling tool, this drilling rod comprises the pin thread (5) that forms near free end (2), described pin thread (5) is have crest (20) and two tooth sides (21, the form of helical thread tooth (5A) 22), described helical thread tooth (5A) defines the same spiral slot (23) with bottom (24), it is characterized in that, described pin thread (5) can be made of martensitic stain less steel, inner shaft at described pin thread is formed with waist (32) to ground, in described waist, described drilling rod has its minimum diameter, form cylindrical guide face (31) between described waist and described pin thread, the diameter of described guide face is greater than the external diameter of described ridge (5A).

7. drilling rod according to claim 6, it is characterized in that, form enveloping surface (30) between described guide face (31) and the described pin thread, the diameter of described enveloping surface is less than the diameter of described guide face, and the groove (23) of described pin thread (5) terminates in the described enveloping surface.

8. according to claim 6 or 7 described drilling rods, it is characterized in that, the waist of described drilling rod (32) converts the hexagonal section (S) or the circular cross-section of described guide face (31) and cross section mode to by the transitional surface (33,34) of the continuous expansion of recessed arch, and the cross-sectional area of described ridge (5A) is greater than the imaginary cross-sectional area of described groove (23).

9. joint sheeve that is used for top hammer rock-drilling tool, described joint sheeve comprises two cavitys (8,9), described cavity stops in the opposite direction, and be separated wall (10) and separate, in described cavity, form negative thread (15,16), it is characterized in that, first negative thread (15) is separated with the free end (11) of columniform interior guide face (35), described first negative thread is to have crest (25) and two tooth sides (26,27) ridge (15A), described ridge (15A) defines the spiral slot (28) with bottom (29), and the width of described ridge is less than the width of described groove.

10. joint sheeve according to claim 9 is characterized in that, described partition wall (10) has axial thickness (L5), and described interior guide face (35) has axial length (L6), and described length is greater than described thickness.

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