KR101638945B1 - Chisel for breaker, and manufacturing method thereof - Google Patents

Chisel for breaker, and manufacturing method thereof Download PDF

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Publication number
KR101638945B1
KR101638945B1 KR1020150101691A KR20150101691A KR101638945B1 KR 101638945 B1 KR101638945 B1 KR 101638945B1 KR 1020150101691 A KR1020150101691 A KR 1020150101691A KR 20150101691 A KR20150101691 A KR 20150101691A KR 101638945 B1 KR101638945 B1 KR 101638945B1
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South Korea
Prior art keywords
heat treatment
chisel
hardness
working
working portion
Prior art date
Application number
KR1020150101691A
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Korean (ko)
Inventor
유장호
유병섭
유다은
최현정
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유장호
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Priority to KR1020150101691A priority Critical patent/KR101638945B1/en
Application granted granted Critical
Publication of KR101638945B1 publication Critical patent/KR101638945B1/en
Priority to PCT/KR2016/007585 priority patent/WO2017014481A1/en

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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F5/00—Dredgers or soil-shifting machines for special purposes
    • E02F5/30—Auxiliary apparatus, e.g. for thawing, cracking, blowing-up, or other preparatory treatment of the soil
    • E02F5/305—Arrangements for breaking-up hard ground
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C21D1/25—Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten")
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/22—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for drills; for milling cutters; for machine cutting tools
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/96—Dredgers; Soil-shifting machines mechanically-driven with arrangements for alternate or simultaneous use of different digging elements
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/96—Dredgers; Soil-shifting machines mechanically-driven with arrangements for alternate or simultaneous use of different digging elements
    • E02F3/966—Dredgers; Soil-shifting machines mechanically-driven with arrangements for alternate or simultaneous use of different digging elements of hammer-type tools
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F5/00—Dredgers or soil-shifting machines for special purposes
    • E02F5/30—Auxiliary apparatus, e.g. for thawing, cracking, blowing-up, or other preparatory treatment of the soil
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/28—Small metalwork for digging elements, e.g. teeth scraper bits
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/28—Small metalwork for digging elements, e.g. teeth scraper bits
    • E02F9/2808—Teeth
    • E02F9/285—Teeth characterised by the material used

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Percussive Tools And Related Accessories (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

Disclosed is a chisel for a breaker and a manufacturing method thereof. The chisel for a breaker according to an embodiment of the present invention includes a mounting portion mounted on a breaker main body and a working portion provided with a mountain-shaped striking portion at a tip end thereof. The working portion includes a central portion provided with a relatively high hardness by a hardening heat treatment, And a peripheral portion having a lower hardness than the central portion.

Description

{Chisel for breaker, and manufacturing method thereof}

The present invention relates to a chisel for a breaker, and more particularly, to a chisel for a breaker capable of maintaining a good crushing performance by keeping the fore end of the work part in a mountain shape in spite of wear due to use, and a manufacturing method thereof.

The breaker is a device that is installed in an excavator such as a construction equipment and performs excavation of the ground, crushing rock, dismantling the building.

As shown in Fig. 1, the breaker is composed of a main body 1 mounted on an excavator or the like and incorporating a hydraulic type striking device, and a crushing device for crushing rocks and concrete by receiving energy (impact force) And a chisel 2 for holding the chisel.

The chisel 2 is detachably mountable to the breaker body 1 so that it can be replaced when it is worn or broken. 2, the chisel 2 can be divided into a mounting portion 2a mounted on the breaker main body 1 and a working portion 2b performing a crushing operation. In addition, the tip end 3 of the working portion 2b is machined into a sharp-pointed shape for the crushing operation.

The distal end 3 of the working portion 2b of the chisel 2 keeps the sharp mountain 3a at the beginning of the work but wears as it is used for the crushing operation and turns into a blunt shape 3b to reduce the crushing effect. That is, after a certain period of use, the crushing force is lowered because the tip is rounded. Therefore, the conventional chisel 2 has to be frequently replaced with a new one during the work, or the tip end of the work part 3 must be machined into a mountain shape to be mounted.

SUMMARY OF THE INVENTION The present invention provides a chisel for a breaker and a method for manufacturing the same, which enables the tip end of a working portion to maintain a mountain-like shape even when worn by use, thereby maintaining a good crushing performance.

The present invention also provides a chisel for a breaker excellent in abrasion resistance and impact resistance and a manufacturing method thereof.

According to an aspect of the present invention, there is provided a hammering device comprising: a mounting portion mounted on a breaker main body; and a working portion provided with a mountain-shaped striking portion at a tip end thereof, wherein the working portion includes a central portion provided with a relatively high hardness by a hardening heat treatment, It is possible to provide a chisel for a breaker including a circumferential portion provided with a lower hardness.

The working portion may be provided such that the hardness gradually increases from the peripheral portion surface toward the center portion.

The mounting portion and the working portion may be formed of the same material, and the center portion of the mounting portion and the working portion may be formed to have the same hardness and strength by the curing heat treatment.

The center portion hardness of the mounting portion and the working portion may be HRC 47 to 52 and the hardness of the peripheral portion of the working portion may be HRC 30 to 36. [

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, the method comprising: a machining step of integrally machining a chisel having a mounting portion mounted on a breaker main body and a work portion provided with a mountain- A hardening heat treatment step of hardening the whole of the chisel after the processing step so as to have a hardness set by the hardening heat treatment; And a softening heat treatment step of locally softening the periphery of the working part after the hardening heat treatment step so that the hardness of the periphery of the working part is lower than the hardness of the central part of the mounting part and the working part, Can be provided.

Wherein the curing heat treatment step comprises a heating step of heating the chisel to a temperature of 850 to 900 DEG C in a heating chamber, a quenching heat treatment step of rapidly cooling the chisel in the cooling liquid after the heating step, And a tempering step of maintaining the temperature at 300 to 350 DEG C for 150 to 170 minutes.

In the softening heat treatment step, the periphery of the working part may be rapidly heated locally and then slowly cooled by a high frequency induction heating method.

The chisel for a breaker according to an embodiment of the present invention has a lower hardness at the periphery of the worker than at the center, so that the periphery wears earlier than the center at the time of use, and the tip of the worker continues to maintain a mountain shape. .

In addition, the breaker chisel according to the embodiment of the present invention is excellent in abrasion resistance and impact resistance because it has a relatively hard hardness surrounding the central portion of the work portion having a high hardness.

1 shows a main body of a general breaker and a chisel mounted thereon.
Fig. 2 shows the wear of the tip of the working part according to the construction and use of a general chisel.
3 shows a configuration of a chisel for a breaker according to an embodiment of the present invention.
4 shows a method of manufacturing a chisel for a breaker according to an embodiment of the present invention.
5 shows an example of softening heat treatment of the periphery of the working portion of the chisel for a breaker according to an embodiment of the present invention by a high frequency induction heating method.
6 is a graph showing a temperature deviation between a surface and a center of the periphery of a working portion of a breaker chisel according to an embodiment of the present invention when locally heating.
7 is a graph showing the hardness of the periphery and the center of the working portion of the breaker chisel according to the embodiment of the present invention.
FIG. 8 shows a wear pattern at the tip of a working part according to the use of the chisel for a breaker according to the embodiment of the present invention.
FIG. 9 shows an example in which the periphery of the working portion of the breaker chuck according to the embodiment of the present invention is stepwise heated locally so that the hardness gradually decreases from the central portion to the peripheral portion of the working portion.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to fully convey the spirit of the present invention to a person having ordinary skill in the art to which the present invention belongs. The present invention is not limited to the embodiments shown herein but may be embodied in other forms. For the sake of clarity, the drawings are not drawn to scale, and the size of the elements may be slightly exaggerated to facilitate understanding.

Referring to FIG. 3, the chisel 10 for a breaker according to the embodiment of the present invention may be in the form of a round bar or a polygonal bar. The chisel 10 has a mounting portion 11 mounted on a breaker and a working portion 12 for receiving impact energy from the breaker in a state exposed to the outside of the breaker (not shown) and crushing rock or concrete.

The mounting portion 11 is provided with a mounting groove 11a formed along the perimeter so that it can be engaged in the breaker and the working portion 12 is provided with a striking portion 13 which is machined to have a pointed mountain shape at the tip for the crushing operation .

Since the mounting portion 11 and the working portion 12 are integrally formed, it is difficult to distinguish them by the naked eye. 3, the mounting portion 11 and the working portion 12 are separately shown for convenience of explanation. The working portion 12 is also divided into a central portion 12a having a relatively high hardness and a peripheral portion 12b having a relatively low hardness around the central portion 12a in a virtual broken line 12c .

The mounting portion 11 and the working portion 12 of the chisel 10 according to the present embodiment are provided by the same material but the mounting portion 11 mounted on the breaker and the central portion 12a of the working portion 12 And the peripheral portion 12b of the working portion 12 is subjected to a softening heat treatment so as to have a relatively low hardness so as to maintain a relatively high hardness and strength, do.

The chisel 10 according to the present embodiment has the hardness and strength of the central portion 12a of the working portion 12 (including the striking portion 13) larger than the peripheral portion 12b of the working portion 12, The tip end of the working portion 12, that is, the striking portion 13, maintains a mountain-like shape and maintains the fracture performance even when the tip of the working portion 12 (the striking portion) . 8, reference numeral 13a denotes a state before use of the striking part 13, and reference numeral 13b denotes a state of wearing the striking part 13 after use.

Next, a method of manufacturing the chisel 10 according to the embodiment of the present invention will be described.

4, the method of manufacturing a chisel according to the present embodiment includes a processing step 21 for processing the shape of the chisel 10, a hardening heat treatment step 22 for hardening the entire chisel 10, And a softening heat treatment step 13 for locally softening and heat-treating the peripheral portion 12b of the working portion 12.

The machining process 21 is a process for manufacturing the chisel 10 having the mounting portion 11 and the working portion 12 as shown in Fig. 3 by processing the metal by forging, cutting, or the like. AISI 4140M2 alloy can be used as the material of the chisel 10, and the composition ratios thereof are shown in Table 1 below. This material can have sufficient hardness and strength to the central portion 12a of the working portion 12 of the chisel 10 through heat treatment and can be made to have a sufficiently high hardness and strength by increasing the molybdenum (Mo) The rigidity can be further enhanced.

Kinds C Si Mn P.S. Cr Mo Fe Composition ratio 0.38 to 0.43 0.15-0.35 0.60 to 0.90 0.030
Below 0.90 to 1.20 0.15-0.35 The remaining weight%

The hardening heat treatment step 22 is a step of heat-treating the entire chisel 10 after processing so as to have a relatively high hardness and strength. The curing heat treatment step 21 includes a heating step of heating the chisel 10 into a heating chamber at a temperature of 850 to 900 캜 and a heating step of heating the chisel 10 heated in the heating step for about 20 minutes A quenching heat treatment step in which the hardness is increased by cooling the quenching heat treatment step, and the quenching heat treatment step in which the chisel 10 is put back into the heating chamber at a temperature of 300 to 350 ° C. for 150 to 170 minutes to impart toughness .

The hardening heat treatment process 22 heat-treats the entire chisel 10 in this manner so that the hardness of the mounting portion 11 and the working portion 12 of the chisel 10 is about 47 to 52 HRC. When the hardening heat treatment process 22 is performed, the chisel 10 has sufficient rigidity to crush the rock or concrete in both the mounting portion 11 and the working portion 12. [

The softening heat treatment step 23 locally softens the peripheral portion 12b of the working portion 12 after the hardening heat treatment step 22 so that the hardness of the peripheral portion 12b of the working portion 12 is reduced, And the hardness of the central portion 12a of the working portion 12 is lowered.

The softening heat treatment step 22 is a softening heat treatment step in which the peripheral portion 12b of the working portion 12 is locally rapidly heated by a high frequency induction heating method and then gradually cooled, 12b. 5, when the coil-shaped induction heating apparatus 30 is disposed outside the peripheral portion 12b of the working portion 12 of the chisel 10, the surface of the peripheral portion 12b is rapidly rotated After heating, cool slowly. At this time, as shown in Fig. 6, the surface of the working portion 12 of the chisel 10 is rapidly heated to raise the temperature, and the central portion 12a is not substantially heated.

The hardness of the peripheral portion 12b of the working portion 12 through the softening heat treatment is about 30 to 36 HRC. The chisel 10 after the softening heat treatment process 23 has the hardness of the central portion 12a of the mounting portion 11 and the working portion 12 of HRC 47 to 52 and the hardness of the peripheral portion 12b of the working portion 12 May be HRC 30-36. That is, the hardness of the working portion 12 gradually increases from the surface of the peripheral portion 12b toward the central portion 12a, as shown in Fig.

The softening heat treatment process 23 can control the heating temperature and the heating depth of the peripheral portion 12b by controlling the output of the induction heating device 30, the supply power frequency, the heating time, and the like. The softening heat treatment step 23 repeats a plurality of times by controlling the output or the like of the induction heating apparatus 30 in such a manner so as to form the peripheral portion 12b from the central portion 12a of the working portion 12 ) Surface may be lowered step by step. In other words, the hardness may be gradually lowered from the center portion 12a to the peripheral portion 12b in the form of A region> B region> C region.

 As described above, since the breaker chisel 10 according to the present embodiment is subjected to the curing heat treatment so that the central portion 12a of the working portion 12 including the mounting portion 11 and the striking portion 13 maintains a relatively high hardness and strength Strength and abrasion resistance for crushing of rock or concrete can be maintained. The peripheral portion 12b of the working portion 12 is subjected to the softening heat treatment at a relatively low hardness to protect the central portion 12a of the working portion 12 to increase the impact resistance, thereby enhancing the durability.

In the breaker chisel 10 according to the present embodiment, since the hardness of the peripheral portion 12b of the working portion 12 is lower than the hardness of the central portion 12a, the peripheral portion 12b is worn before the central portion 12a Therefore, even when the striking portion 13 is worn by use, the striking portion 13 maintains a mountain shape and can maintain a good crushing performance even if it is used for a long time.

Since the manufacturing method of the breaker chisel 10 according to the present embodiment performs the hardening heat treatment step 22 and the softening heat treatment step 23 as described above after the processing step 21, the entire manufacturing process is simple It is possible to manufacture the chisel 10 having the excellent fracture performance, impact resistance and abrasion resistance while minimizing the cost.

10: chisel, 11: mounting part,
12: working part, 12a: central part of working part,
12b: circumferential portion of the working portion, 13: striking portion,
21: a processing step, 22: a curing heat treatment step,
23: Softening heat treatment process.

Claims (7)

A chisel for a breaker, comprising: a mounting portion mounted on a breaker main body; and a working portion provided with a mountain-shaped striking portion at its tip,
Wherein the working portion includes a central portion provided with a relatively high hardness by a hardening heat treatment and a peripheral portion provided with a hardness lower than that of the center portion by softening heat treatment so that the hitting portion can be maintained in a mountain- Chisel. The method according to claim 1,
Wherein the working portion gradually increases in hardness from the peripheral surface to the central portion. 3. The method according to claim 1 or 2,
Wherein the mounting portion and the working portion are made of the same material,
Wherein the mounting portion and the central portion of the working portion are provided with the same hardness and strength by the hardening heat treatment. The method according to claim 1,
The center portion hardness of the mounting portion and the working portion is HRC 47 to 52,
And the peripheral portion hardness of the working portion is HRC 30 to 36. A machining step of integrally machining a chisel having a mounting portion mounted on the breaker main body and a working portion provided with a mountain-shaped striking portion at its tip;
A hardening heat treatment step of hardening the whole of the chisel after the processing step so as to have a hardness set by the hardening heat treatment; And
Wherein the periphery of the working portion is locally subjected to a softening heat treatment after the hardening heat treatment step to soften the periphery of the working portion so that the hardness of the periphery of the working portion becomes lower than the hardness of the central portion of the mounting portion and the working portion, A method of manufacturing a chisel for a breaker including a heat treatment process. 6. The method of claim 5,
The curing heat treatment process
A heating step of heating the chisel at a temperature of 850 to 900 DEG C in a heating chamber,
A quenching heat treatment step of cooling the chisel in the cooling liquid after the heating step,
And a tempering heat treatment step of maintaining the chisel at a temperature of 300 to 350 DEG C for 150 to 170 minutes in the heating chamber after the quenching heat treatment step. The method according to claim 5 or 6,
The softening heat treatment step
Wherein the peripheral portion of the working portion is locally rapidly heated by a high frequency induction heating method, and then slowly cooled.
KR1020150101691A 2015-07-17 2015-07-17 Chisel for breaker, and manufacturing method thereof KR101638945B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1020150101691A KR101638945B1 (en) 2015-07-17 2015-07-17 Chisel for breaker, and manufacturing method thereof
PCT/KR2016/007585 WO2017014481A1 (en) 2015-07-17 2016-07-13 Chisel for breaker and method for manufacturing same

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KR1020150101691A KR101638945B1 (en) 2015-07-17 2015-07-17 Chisel for breaker, and manufacturing method thereof

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20170117357A (en) * 2017-10-11 2017-10-23 이찬주 A Point Chisel Having an Extended Life Span

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210301361A1 (en) * 2020-03-31 2021-09-30 Caterpillar Inc. Tool for a hydraulic hammer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63237877A (en) * 1987-03-26 1988-10-04 大同特殊鋼株式会社 Method of thermally treating rod for rock drill
JPH0812220B2 (en) * 1984-03-29 1996-02-07 株式会社東芝 Transmission line fault locator
KR20100047676A (en) * 2008-10-29 2010-05-10 임행주 Method for manufacturing the chisel pin
KR20120031541A (en) * 2010-09-25 2012-04-04 이원기 Breaker chisel

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4812220B2 (en) * 2002-05-10 2011-11-09 株式会社小松製作所 High hardness and toughness steel
KR100768775B1 (en) * 2006-05-18 2007-11-05 주식회사 티엠시 A chisel of hydraulic breaker and a method for producing it

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0812220B2 (en) * 1984-03-29 1996-02-07 株式会社東芝 Transmission line fault locator
JPS63237877A (en) * 1987-03-26 1988-10-04 大同特殊鋼株式会社 Method of thermally treating rod for rock drill
KR20100047676A (en) * 2008-10-29 2010-05-10 임행주 Method for manufacturing the chisel pin
KR20120031541A (en) * 2010-09-25 2012-04-04 이원기 Breaker chisel

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20170117357A (en) * 2017-10-11 2017-10-23 이찬주 A Point Chisel Having an Extended Life Span

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