CN218953314U - Wear-resistant inserted hob and shield cutter head for hard rock shield - Google Patents
Wear-resistant inserted hob and shield cutter head for hard rock shield Download PDFInfo
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- CN218953314U CN218953314U CN202222400102.5U CN202222400102U CN218953314U CN 218953314 U CN218953314 U CN 218953314U CN 202222400102 U CN202222400102 U CN 202222400102U CN 218953314 U CN218953314 U CN 218953314U
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Abstract
The utility model provides a wear-resistant inserted hob for a hard rock shield and a shield cutter head. The wear-resistant gear hob comprises a hob body and a hob ring; the cutter ring is circumferentially arranged on the outer side of the cutter body and in interference fit with the cutter body, a first wear-resistant part is arranged on the cutter ring, the first wear-resistant part is arranged on the outermost periphery of the cutter ring and comprises a plurality of alloy teeth which are circumferentially uniformly and alternately inlaid on the outermost periphery of the cutter ring, the first height of the surface of the cutter ring is protruded in the middle of the alloy teeth, the second height of the surface of the cutter ring is protruded on the left side and the right side, and the second height is larger than the first height. According to the wear-resistant inserted hob for the hard rock shield, the first wear-resistant part is additionally arranged on the cutter ring, so that the wear speed of the cutter ring is reduced, the wear resistance and the impact resistance of the cutter ring are improved, meanwhile, the wear-resistant inserted hob for the hard rock shield has high strength, toughness, good hardenability and overheat resistance stability, the whole service life of the cutter is further prolonged, and the rock breaking efficiency is improved.
Description
Technical Field
The utility model relates to the technical field of tunneling, in particular to a wear-resistant inserted hob and a shield cutter head for a hard rock shield.
Background
In the full-section hard rock stratum, the cutter is extremely easy to wear, and special conditions such as eccentric wear, tipping, cutter ring chipping, blade rolling and the like can also occur besides normal wear, in the construction process, the earth pressure balance shield construction generally adopts a round blade hob to break the rock due to the fact that bedrock fracture water is more, the face is more complete and the like, but on-site actual tool changing times and actual measured wear data show that the wear condition of the cutter is still serious, a large amount of construction period is wasted, and huge economic loss is caused.
The prior art improves the situation by improving the hob ring, and the hob ring mainly comprises a round blade, a spherical insert and a constant section; the round-blade hob has higher rock breaking efficiency than the spherical-shaped tipped and normal-section hob, but the cutter ring has higher abrasion speed and lower tunneling distance, so that the construction period and the cost are increased; when the spherical inserted hob is driven, the hob vibration is aggravated, a great amount of rock powder is easily generated when the hob contacts with the face, so that the hob is in a running state with high consumption and low rock breaking efficiency, the abrasion of the hob is accelerated, the impact load received by the hob is obvious at the junction of a soft rock layer and a hard rock layer, and the phenomenon of tooth falling is easily caused if the rotating speed of the hob is too high; the constant section hob has lower abrasion rate and longer tunneling distance due to the flat cutter ring, but has lower rock breaking efficiency than a round blade and a spherical inserted hob.
Currently, the ways of improving wear resistance of hob rings are mostly two: one is to improve the wear resistance by a heat treatment process; the other is to inlay tungsten carbide alloy at the cutting edge of the knife ring. However, the two treatment modes have higher requirements on the heat treatment process, the toughness of the cutter ring can be reduced while the hardness and the wear resistance are improved, so that the impact resistance is reduced, the cutter ring is easy to crack in construction, and the service life cannot meet the requirements.
Therefore, there is a need to further develop a new hob with a low wear rate and a high service life, considering the effect of the hob on wear resistance when driving in hard rock formations, from the hob tooth shape and material point of view.
Disclosure of Invention
In view of the defects of the prior art, the main purpose of the utility model is to provide the wear-resistant inserted hob for the hard rock shield, so as to solve the problems of wear resistance, easy cracking and falling off and short service life of the hob in the prior art.
The utility model also provides a shield cutter head to meet the shield construction requirements of actual engineering.
The technical scheme of the utility model is as follows:
a hard rock shield wear resistant insert hob comprising:
a cutter body;
knife ring, follow the external side circumference of knife is set up, the knife ring is equipped with first wear-resisting portion, first wear-resisting portion sets up in the outermost periphery of knife ring, including circumference evenly spaced inlay at a plurality of alloy teeth of knife ring outermost periphery, alloy teeth certainly knife ring surface upwards protrudes to the protruding knife ring surface first height in the middle of the alloy teeth, the protruding knife ring surface second height of left and right sides, just the second height is greater than first height.
In some embodiments, 42 alloy teeth are inlaid at equal intervals in the circumferential direction of the outermost circumference of the cutter ring.
In some embodiments, the alloy teeth are 22mm in length and 20mm in width.
In some embodiments, the first height is 1-2mm and the second height is 2-4mm.
In some embodiments, the cutter ring is further provided with a second wear portion disposed circumferentially on both sides of the first wear portion, including an annular wear layer coated on both sides.
In some embodiments, the annular wear layer has a width of 40mm.
In some embodiments, the second wear portion is an annular wear layer coated with tungsten carbide.
In some embodiments, the hob is an 18 "single-bladed tipped hob with a diameter of 457.2mm.
In some embodiments, the hob width is 334.7mm and the cutter body width is 225mm.
A shield cutterhead is provided with the wear-resistant inserted hob for hard rock shield.
Compared with the prior art, the utility model has the beneficial effects that: the utility model provides a wear-resistant insert hob and a shield cutter head for a hard rock shield, wherein the wear-resistant insert hob for the hard rock shield reduces the wear speed of a cutter ring, improves the wear resistance and impact resistance of the cutter ring, simultaneously ensures that the wear-resistant insert hob for the hard rock shield has high strength, toughness, good hardenability and overheat resistance stability, further improves the whole service life of the cutter, and improves the rock breaking efficiency. Specifically, it has at least the following practical effects:
the alloy teeth of the first wear-resisting part are provided with a first height protruding from the surface of the cutter ring in the middle, the left side and the right side are provided with a second height protruding from the surface of the cutter ring, the alloy teeth are provided with the second height protruding from the surface of the cutter ring in the middle and the two sides, the first surface of the cutter ring is used for enabling the alloy teeth to be firstly contacted with rock strata of an excavation surface in the rock breaking process, the cutter ring is protected, the wear resistance of the cutter ring is improved, and the second surface is reserved for the alloy teeth to have a certain invasion depth, so that the rock breaking efficiency of the wear-resisting inserted hob for the hard rock shield is improved.
The second height is larger than the first height, so that the angle of the alloy tooth edge is not too small in order to control the angle of the alloy tooth top edge, namely the alloy tooth top is not too sharp, the alloy tooth is prevented from cracking and falling, and the impact resistance of the alloy tooth edge angle is improved.
The annular wear-resistant layer arranged on the second wear-resistant part enables the wear-resistant inserted hob for the hard rock shield to have high strength, toughness, good hardenability and stability against overheating, and the annular wear-resistant layer is coated on the surface of the cutter ring, so that the wear rate of the cutter can be effectively slowed down.
It should be understood that the implementation of any of the embodiments of the utility model is not intended to simultaneously possess or achieve some or all of the above-described benefits.
Drawings
In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those of ordinary skill in the art that the drawings in the following description are exemplary only and that other implementations can be obtained from the extensions of the drawings provided without inventive effort.
The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the utility model, which is defined by the claims, but rather by the claims.
FIG. 1 is a front view of a hard rock shield wear-resistant insert hob according to an embodiment of the present utility model;
FIG. 2 is a side view of a hard rock shield wear insert hob according to an embodiment of the present utility model;
FIG. 3 is a front view of an alloy tooth construction according to one embodiment of the utility model;
FIG. 4 is a side view of an alloy tooth structure according to one embodiment of the utility model.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the embodiments of the present utility model will be described in further detail with reference to the embodiments and the accompanying drawings. The exemplary embodiments of the present utility model and their descriptions herein are for the purpose of explaining the present utility model, but are not to be construed as limiting the utility model.
In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.
It should be understood that the terms "comprises/comprising," "consists of … …," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such product, apparatus, process, or method as desired. Without further limitation, an element defined by the phrases "comprising/including … …," "consisting of … …," and the like, does not exclude the presence of other like elements in a product, apparatus, process, or method that includes the element.
It is further understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship based on that shown in the drawings, merely to facilitate describing the present utility model and to simplify the description, and do not indicate or imply that the devices, components, or structures referred to must have a particular orientation, be configured or operated in a particular orientation, and are not to be construed as limiting the present utility model.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.
The wear-resistant inserted hob for the hard rock shield provided by the utility model has the advantages that the cutter ring has high strength and toughness, the wear speed of the cutter ring can be effectively reduced, the wear resistance and impact resistance of the cutter ring are improved, the hob is not easy to crack and fall off when the hob breaks rocks, the whole service life of the cutter can be further prolonged, and the rock breaking efficiency is improved.
The implementation of the present utility model will be described in detail with reference to the preferred embodiments.
The utility model provides a wear-resistant inserted hob for a hard rock shield, which is shown in fig. 1 and 2 and comprises a hob body 1 and a hob ring 2.
Specifically, the cutter ring 2 is circumferentially arranged along the outer side of the cutter body 1 and in interference fit with the cutter body 1, the cutter ring 2 is provided with a first wear-resistant part 21, the first wear-resistant part 21 is arranged on the outermost periphery of the cutter ring 2, a plurality of alloy teeth 210 are circumferentially uniformly and alternately embedded on the outermost periphery of the cutter ring 2, the alloy teeth 210 protrude upwards from the surface of the cutter ring, the middle of the alloy teeth protrudes to a first height from the surface of the cutter ring 2, the left side and the right side protrude to a second height from the surface of the cutter ring 2, and the second height is larger than the first height.
According to the utility model, the plurality of alloy teeth 210 are uniformly embedded at intervals in the circumferential direction of the outermost periphery of the cutter ring 2 as the first wear-resistant part 21, the plurality of alloy teeth 210 are contacted with the rock surface to play a role of cutting and crushing, the plurality of alloy teeth 210 continuously expand initial cracks generated by impact crushing to lateral cracks of the rock surface and branch cracks of the rock surface, and the lateral cracks of the rock surface caused by the alloy teeth 210 are fully developed and communicated with each other, so that the rock surface is promoted to peel, the rock breaking is facilitated, and the rock breaking efficiency is improved.
The alloy teeth 210 of the first wear-resistant part 21 are provided with a first height protruding from the surface of the cutter ring 2 in the middle, and a second height protruding from the surface of the cutter ring 2 is provided on the left and right sides, and the middle and two sides of the alloy teeth 210 are provided with the surfaces protruding from the cutter ring 2, firstly, in order to enable the alloy teeth 210 to be firstly contacted with rock strata on an excavation surface in the rock breaking process, the cutter ring 2 is protected, the wear resistance of the cutter ring 2 is improved, secondly, a certain invasion depth is reserved for the alloy teeth 210, and the rock breaking efficiency of the wear-resistant cutting hob for the hard rock shield is improved.
With continued reference to fig. 1 and 2, the alloy teeth 210 are embedded on the outermost periphery of the cutter ring 2 in a protruding manner, and because the outermost ends of the cutter ring 2 form an included angle along the two sides of the cutter ring 2, the alloy teeth 210 are formed with a first height and a second height along the two sides of the alloy teeth, which are higher than the first height, so that the angle of the top edge of the alloy teeth 210 is controlled, the angle of the alloy teeth is not too small, i.e. the top of the alloy teeth 210 is not too sharp, the alloy teeth 210 are prevented from cracking and falling off during rock breaking, and the impact resistance of the edge angle of the alloy teeth 210 is improved.
Preferably, the cutter ring 2 is made of a 40CrNiMo steel material.
In the utility model, the alloy teeth 210 are hard alloy teeth, the chemical components of the hard alloy teeth are mainly tungsten carbide (WC) and binder cobalt (Co), the alloy teeth 210 are made of hard alloy, the overall hardness, toughness and wear resistance of the cutter ring 2 are improved, and the impact resistance is stronger.
Preferably, the alloy teeth 210 are made of cemented carbide with model YG 15C.
In some embodiments, referring to fig. 2, a plurality of alloy teeth 210 are uniformly embedded at intervals in the circumferential direction of the cutter ring 2, and the plurality of alloy teeth 210 which are uniformly distributed improve the wear resistance of the cutter ring 2 in the circumferential direction, prolong the service life of the cutter ring 2, reduce the cutter changing frequency of the shield tunneling machine, and improve the overall rock breaking efficiency.
It should be appreciated that the number of alloy teeth 210 inlaid at the outermost periphery of cutter ring 2 is related to the diameter of the specific use of the cutter ring 2 at the construction site, and it is preferred herein that the alloy teeth 210 are inlaid 42 at evenly spaced intervals circumferentially at the outermost periphery of the cutter ring 2.
Referring to fig. 3, the alloy teeth 210 are approximately polygonal in structure, and the polygonal alloy teeth are symmetrical about a plane in which axes thereof lie as a whole. The specific shape of the alloy teeth 210 is not set forth herein.
Preferably, the alloy teeth 210 are 22mm in length and 20mm in width, it being understood that the length and width are the length and width of the cross-sectional dimensions thereof.
In the present utility model, the length and width of the alloy teeth 210 are not greatly different, so that the alloy teeth 210 can be prevented from bearing larger impact when breaking rock.
In some embodiments, the first height of the middle of the alloy tooth 210 protruding from the surface of the cutter ring 2 is 1-2mm, and the second height of the left and right sides of the alloy tooth 210 protruding from the surface of the cutter ring 2 is 2-4mm.
Preferably, referring to fig. 4, it is preferred herein that the first height of the surface of the cutter ring 2 protruding from the middle of the alloy tooth 210 is 1mm, and the second height of the surface of the cutter ring 2 protruding from the left and right sides of the alloy tooth 210 is 3mm.
In the utility model, the first height is set to be 1mm, so that the abrasion resistance of the whole cutter ring 2 is improved, and the impact property is reduced; the second height is set to be 3mm, and the rock breaking efficiency can be improved due to the fact that the hob breaks rock, the cutter extrudes and shears to break rock mass of the face, and the cutter rings 2 on two sides are protected to improve the overall wear resistance of the cutter rings 2.
In some embodiments, see fig. 1 and 2, the cutter ring 2 is further provided with a second wear part 22, which second wear part 22 is arranged circumferentially on both sides of the first wear part 21, comprising an annular wear layer coated on both sides.
In the utility model, the annular wear-resistant layers are coated on the two sides of the cutter ring 2, and the annular wear-resistant layer material has good wear resistance and hardness, so that the wear rate of the cutter ring 2 can be effectively slowed down, the service life of the cutter ring 2 is prolonged, and the cutter changing frequency is reduced.
Preferably, the second wear portion 22 is an annular wear layer coated with tungsten carbide.
The width design of the annular wear-resistant layer is set according to the maximum penetration of the hob, namely when the hob invades the rock mass to the maximum depth (such as 30mm depth), the place where the cutter ring 2 is in direct contact with the rock mass is covered by the wear-resistant layer.
Preferably, the annular wear layer has a width of 40mm.
According to the utility model, the first wear-resistant part 21 and the second wear-resistant part 22 are arranged on the periphery of the cutter ring 2, the first wear-resistant part 21 is a plurality of alloy teeth 210 which are uniformly embedded on the outermost periphery of the cutter ring 2 at intervals along the circumferential direction, the alloy teeth 210 have high strength and toughness, and as the first wear-resistant part 21 is arranged on the outermost periphery of the cutter ring 2, when a cutter digs a hard rock stratum, the first wear-resistant part 21 firstly contacts the rock stratum and breaks the rock stratum, the first wear-resistant part 21 firstly forms a first-stage protection on the cutter ring 2, the integral impact resistance is improved, the cutter ring 2 starts to contact the rock stratum in the process of extending the first wear-resistant part 21 into the rock stratum, and the second wear-resistant part 22 is circumferentially arranged on both sides of the first wear-resistant part 21, namely the wear resistance of the cutter ring 2 is improved to protect the cutter ring 2, so that the second-stage protection of the cutter ring 2 is formed.
The cutter ring 2 forms double protection of one stage and two stages, so that the hob has high strength and toughness, good hardenability and overheat resistance stability, can effectively break rock, reduces the cutter changing frequency of a shield machine, and prolongs the service life of a cutter.
In some embodiments, referring to FIG. 1, the hob of the present utility model is an 18 "single-bladed, tipped hob with a diameter of 457.2mm.
Preferably, the width of the hob is 334.7mm, and the width of the cutter body 1 is 225mm.
In some embodiments, referring to fig. 2, the hob further comprises a hob shaft 3, which hob shaft 3 is arranged in the centre of the hob body 1. It is easy to understand that the cutter shaft 3 is a transmission shaft of the cutter and is used for being fixed on the cutter base.
Preferably, the center of the cutter shaft 3 is provided with a center hole, the section of the cutter shaft 3 is in an irregular hexagon shape, and the cutter shaft is formed by connecting three straight lines and three arc lines at intervals. The hob is designed to have the shape which is convenient for fixing the hob shaft 3 on one hand and convenient for installing and dismantling on the other hand, and improves the vibration resistance of the hob during rock breaking.
The utility model also provides a shield cutter head, which is provided with the wear-resistant inserted hob for the hard rock shield.
The utility model provides a wear-resistant insert hob for a hard rock shield, which reduces the wear speed of a cutter ring, improves the wear resistance and impact resistance of the cutter ring, simultaneously ensures that the wear-resistant insert hob for the hard rock shield has high strength, toughness, good hardenability and overheat resistance stability, further improves the whole service life of a cutter and improves the rock breaking efficiency.
It is easy to understand by those skilled in the art that the above preferred embodiments can be freely combined and overlapped without conflict.
The foregoing description of the preferred embodiments of the utility model is not intended to limit the utility model to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the utility model.
Claims (9)
1. The utility model provides a hard rock shield constructs with wear-resisting gear hobbing cutter which characterized in that includes:
a cutter body;
the cutter ring is circumferentially arranged along the outer side of the cutter body, a first wear-resistant part is arranged on the outermost periphery of the cutter ring, the cutter ring comprises a plurality of alloy teeth which are uniformly and circumferentially inlaid on the outermost periphery of the cutter ring at intervals, the alloy teeth protrude upwards from the surface of the cutter ring, the middle of the alloy teeth protrude by a first height from the surface of the cutter ring, the left side and the right side protrude by a second height from the surface of the cutter ring, and the second height is larger than the first height; the cutter ring is further provided with a second wear-resistant part, the second wear-resistant part is arranged on two sides of the first wear-resistant part in a surrounding mode, and the second wear-resistant part comprises annular wear-resistant layers coated on two sides.
2. The hard rock shield wear-resistant insert hob according to claim 1, wherein the alloy teeth are uniformly embedded with 42 alloy teeth at intervals in the circumferential direction of the outermost circumference of the hob ring.
3. The hard rock shield wear-resistant insert hob according to claim 1, characterized in, that the alloy teeth have a length of 22mm and a width of 20mm.
4. The hard rock shield wear-resistant insert hob according to claim 1, characterized in, that the first height is 1-2mm and the second height is 2-4mm.
5. The hard rock shield wear-resistant insert hob according to claim 1, characterized in, that the annular wear layer has a width of 40mm.
6. The hard rock shield wear-resistant insert hob according to claim 1, characterized in, that the second wear part is an annular wear layer coated with tungsten carbide.
7. The hard rock shield wear-resistant insert hob according to claim 1, characterized in, that the hob is an 18 "single-bladed insert hob with a diameter of 457.2mm.
8. The hard rock shield wear-resistant insert hob according to claim 7, characterized in, that the hob width is 334.7mm and the hob body width is 225mm.
9. A shield cutterhead on which the wear-resistant tipped hob for hard rock shield according to any one of claims 1 to 8 is mounted.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN202222400102.5U CN218953314U (en) | 2022-09-09 | 2022-09-09 | Wear-resistant inserted hob and shield cutter head for hard rock shield |
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CN202222400102.5U CN218953314U (en) | 2022-09-09 | 2022-09-09 | Wear-resistant inserted hob and shield cutter head for hard rock shield |
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CN218953314U true CN218953314U (en) | 2023-05-02 |
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CN202222400102.5U Active CN218953314U (en) | 2022-09-09 | 2022-09-09 | Wear-resistant inserted hob and shield cutter head for hard rock shield |
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- 2022-09-09 CN CN202222400102.5U patent/CN218953314U/en active Active
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