JPH03161219A - Manufacture of drill bit for concrete boring - Google Patents
Manufacture of drill bit for concrete boringInfo
- Publication number
- JPH03161219A JPH03161219A JP30029689A JP30029689A JPH03161219A JP H03161219 A JPH03161219 A JP H03161219A JP 30029689 A JP30029689 A JP 30029689A JP 30029689 A JP30029689 A JP 30029689A JP H03161219 A JPH03161219 A JP H03161219A
- Authority
- JP
- Japan
- Prior art keywords
- drill bit
- shank
- cutting blade
- cutting edge
- surface hardness
- 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.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 238000005520 cutting process Methods 0.000 claims abstract description 29
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000000463 material Substances 0.000 claims abstract description 4
- 229910052742 iron Inorganic materials 0.000 claims abstract description 3
- 239000000956 alloy Substances 0.000 claims abstract 2
- 229910045601 alloy Inorganic materials 0.000 claims abstract 2
- 238000005553 drilling Methods 0.000 claims description 12
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 abstract description 12
- 238000010791 quenching Methods 0.000 abstract description 5
- 230000000171 quenching effect Effects 0.000 abstract description 5
- 229910000831 Steel Inorganic materials 0.000 abstract description 3
- 239000010959 steel Substances 0.000 abstract description 3
- 238000005299 abrasion Methods 0.000 abstract 1
- 238000003287 bathing Methods 0.000 abstract 1
- 238000005255 carburizing Methods 0.000 description 7
- 230000005540 biological transmission Effects 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 241001391944 Commicarpus scandens Species 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
Landscapes
- Processing Of Stones Or Stones Resemblance Materials (AREA)
Abstract
Description
【発明の詳細な説明】
本発明はハンマードリルに装着しコンクリート等に穿孔
を行うドリルビットの製造法に関するものである．
〔発明の背景〕
コンクリート等に穿孔を行うドリルビットは、ビットボ
ディ先端に切刃となる超硬チップを接合したものであり
、電動による回転及び打撃機構を有するハンマードリル
本体にドリルビットのシャンク部を装着し、回転及び打
撃力を負荷して先端切刃部においてコンクリート等を穿
孔するものである。このような公知のドリルビットにお
いては，回転トルク及び打撃力を伝達されるシャンク部
とハンマードリル本体の取付部及び切刃部とコンクリー
ト等の被加工物との摩擦は避けられず、耐摩耗性と高強
度を要求されるため、ドリルビットのボディは通常鉄鋼
材料を使用し浸炭焼入処理が施されている。しかし、従
来の浸炭焼入処理では浸炭硬化層を深くすると、熱処理
後のボディの変形を機械的に矯正する際に折損するため
、硬化層は０．２〜０．５ａ＋＋と浅くしている，また
、ボディの切刃部は、熱処理後に超硬チップを高周波等
により局部加熱してロー付け接合されているので、他の
部位に比べて著しく硬さが低下している。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a drill bit that is attached to a hammer drill and used to drill holes in concrete, etc. [Background of the Invention] A drill bit for drilling holes in concrete, etc. has a carbide tip that serves as a cutting edge attached to the tip of the bit body, and the shank portion of the drill bit is attached to a hammer drill body that has an electric rotation and impact mechanism. It is used to drill holes in concrete, etc. at the tip of the cutting edge by applying rotation and impact force. In such known drill bits, friction between the shank part, which transmits rotational torque and impact force, the mounting part of the hammer drill body, the cutting edge part, and the workpiece such as concrete is unavoidable, and wear resistance is reduced. Because high strength is required, the body of drill bits is usually made of steel and carburized and quenched. However, in conventional carburizing and quenching, if the carburized hardened layer is made deep, it will break when mechanically correcting the deformation of the body after heat treatment, so the hardened layer is made as shallow as 0.2 to 0.5a++. Further, the cutting edge portion of the body is brazed and joined by locally heating the carbide tip using high frequency or the like after heat treatment, so the hardness is significantly lower than that of other portions.
したがって、コンクリート等の穿孔において使用時間の
経過と共に摩擦部は摩耗し、シャンク部は回転トルク伝
達が不能に、切刃部はコンクリート粉砕粉の排出不良に
よる超硬チップの摩耗を促進し穿孔能力が低下してドリ
ルビットとしての機能を失っていた。さらに、穿孔時に
切刃の食い込みによる回転のロック等の異常応力が加わ
った場合に、硬さの低い切刃部から折損することがあっ
たこのような背景から，ボディのシャンク部及び切刃部
の耐摩耗性が高く、かつ，靭性のあるドリルビットの開
発が望まれていた。Therefore, when drilling concrete, etc., the friction part wears out over time, the shank part becomes unable to transmit rotational torque, and the cutting part accelerates wear of the carbide tip due to poor discharge of crushed concrete powder, reducing the drilling ability. It had deteriorated and lost its function as a drill bit. Furthermore, if abnormal stress is applied such as locking of rotation due to biting of the cutting edge during drilling, the cutting edge may break due to its low hardness.Because of this background, the shank and cutting edge of the body It has been desired to develop a drill bit with high wear resistance and toughness.
本発明の目的は、上記した欠点を無くすため、ドリルビ
ットボディのシャンク部及び切刃部に耐摩耗性を付与し
、さらにボディに靭性を付加した長寿命ドリルビットの
製造法を提供することにある。An object of the present invention is to provide a method for manufacturing a long-life drill bit in which wear resistance is imparted to the shank portion and cutting edge portion of the drill bit body, and toughness is added to the body, in order to eliminate the above-mentioned drawbacks. be.
第１図はドリルビットの全体図であり、ボディ（１）と
先端に接合された超硬チップ（２）で構成されている。FIG. 1 is an overall view of the drill bit, which consists of a body (1) and a carbide tip (2) joined to the tip.
ドリルピット各部を機能別に分けると、先端の切刃部（
３）、リード溝部（４）及びシャンク部（５）とに分け
られ、シャンク部の回転及び打撃伝達部（６）の横断面
形状は六角、四角及びスプライン形等がある。第２図は
六角シャンク形ドリルビットとハンマードリル本体との
接続図であり、ドリルビットは本体のセカンドハンマー
（７）を介して、シリンダー（８）とハンマー（９）に
より回転及び打撃力を負荷される。If we divide each part of the drill pit by function, we can see that the cutting edge at the tip (
3) It is divided into a lead groove part (4) and a shank part (5), and the cross-sectional shape of the rotation and impact transmission part (6) of the shank part can be hexagonal, square, spline, etc. Figure 2 is a connection diagram of the hexagonal shank type drill bit and the hammer drill body, and the drill bit is loaded with rotational and impact force by the cylinder (8) and hammer (9) through the second hammer (7) of the body. be done.
第３図は六角シャンク形ドリルビットの回転及び打撃伝
達部（６）とセカンドハンマー（７）の横断面形状を示
したものであり，動作時においてセカンドハンマー（７
）はＡの方向に回転し、ドリルビット六角部の角と密着
して回転トルクが伝達されるため，使用時間の経過と共
に角部が摩耗し、遂にはセカンドハンマーが空転しトル
ク伝達が不能になる。なお、セカンドハンマー（７）は
通常鉄系材料から威り，その表面硬さはＨｖ７５０以上
として耐摩耗性の向上が図れれる。Figure 3 shows the cross-sectional shapes of the rotation and impact transmission part (6) and the second hammer (7) of the hexagonal shank type drill bit.
) rotates in the direction of A, and the rotational torque is transmitted through close contact with the hexagonal corner of the drill bit, so the corner wears out over time, and eventually the second hammer becomes idling and torque transmission becomes impossible. Become. The second hammer (7) is usually made of iron-based material, and its surface hardness is set to Hv750 or higher to improve wear resistance.
本発明者らは、強靭で耐摩耗性を有するドリルビットを
開発すべく，種々検討した結果，以下に示す製造工程に
より目的を達或できることを見い出した。すなわち、鉄
鋼材料より成るドリルビットボディに浸炭処理を施した
のち，熱浴中に焼入れしてボディの表面硬さをＨ ｖ
３ ５ ０〜５００とし、次に高周波加熱装置のように
部分加熱のできる炉を用いて切刃部に超硬チップをロー
付けすると同時にシャンク部も同時に加熱したのち焼入
れし、切刃部とシャンク部の表面硬さをＨｖ６００〜７
５０、硬化層深さをＬ．Ｏｍとするものである。なお、
浸炭処理によるボディの表面炭素濃度は０．４０−０．
６０％となるようにする。The inventors of the present invention have conducted various studies to develop a drill bit that is strong and wear-resistant, and have found that the purpose can be achieved by the manufacturing process described below. That is, after carburizing a drill bit body made of steel material, it is quenched in a hot bath to reduce the surface hardness of the body to Hv.
350 to 500, then braze the carbide tip to the cutting edge using a furnace capable of partial heating such as a high-frequency heating device, heat the shank at the same time, and then harden the cutting edge and shank. The surface hardness of the part is Hv600~7
50, hardened layer depth L. Om. In addition,
The surface carbon concentration of the body after carburizing is 0.40-0.
Set it to 60%.
ここで、熱浴焼入れによるボディの表面硬さをＨ ｖ
３ ５ ０〜５００としたのは、ボディに靭性を付与し
熱処理後の変形矯正時及び使用時の折損を防止するため
であり、Ｈｖ３５０以下では、軟か過ぎて変形して使用
に耐えず、Ｈ ｖ ５ ０ ０以上では硬過ぎて靭性を
失い、熱処理後の変形矯正時及び使用時に折損し易くな
る．切刃部とシャンク部の表面硬さをＨｖ６００〜７５
０としたのは、両部の耐摩耗性を高めるためであり、Ｈ
ｖ６００以下では耐摩耗性が低く，寿命が短かくなり、
Ｈｖ７５０以上ではシャンク部と嵌合するハンマードリ
ル本体のセカンドハンマーの摩耗を早め、本体寿命を短
かくするためである，
硬化層深さを１．Ｏｎ以上としたのは、シャンク部の摩
耗寿命は約ｌｍなのでシャンク部の摩耗による表面硬さ
低下を最大限抑え，長寿命を得るためである。また、ボ
ディの表面炭素濃度を０．４０〜０．６０％としたのは
、０．４０％以下では切刃部及びシャンク部の表面硬さ
をＨｖ６００以上とすることが困難なためであり、０．
６０以上では熱浴焼入れにおいて表面硬さをＨｖ３６０
〜５００とするための熱浴温度が高くなり、ボディ心部
硬さが低くなって靭性を低下させるためである。Here, the surface hardness of the body due to hot bath quenching is H v
350 to 500 is in order to impart toughness to the body and prevent breakage during deformation correction after heat treatment and during use.If Hv is less than 350, it will be too soft and deformed to withstand use. If Hv500 or more, it becomes too hard and loses toughness, making it easy to break during correction of deformation after heat treatment and during use. The surface hardness of the cutting edge and shank is Hv600-75.
The reason for setting it to 0 is to increase the wear resistance of both parts, and H
Below v600, the wear resistance is low and the lifespan is shortened.
At Hv750 or higher, the hardened layer depth should be set to 1. The reason why it is set to On or more is to minimize the decrease in surface hardness due to wear of the shank and obtain a long life since the wear life of the shank is approximately 1 m. In addition, the reason why the surface carbon concentration of the body is set to 0.40 to 0.60% is because if it is less than 0.40%, it is difficult to make the surface hardness of the cutting edge part and shank part Hv600 or more. 0.
60 or higher, the surface hardness is reduced to Hv360 in hot bath quenching.
This is because the hot bath temperature for setting the temperature to 500°C becomes high, which lowers the hardness of the core of the body and lowers the toughness.
以上の条件の中で最も適切な条件は、浸炭処理後の熱浴
焼入れによる硬さ；Ｈｖ４００、切刃部及びシャンク部
の表面硬さ； Ｈ ｖ ７ ０ ０、硬化層深さ；１．
５ｍｏ＋で、浸炭処理時の表面炭素濃度；０．５０％で
ある，
〔発明の実施例〕
第４図は、本発明ドリルビットの長さ方向の表面硬さ及
び内部硬さ分布であり，第５図は本発明ドリルビットと
従来のドリルビットのシャンク部の断面硬さ分布を示し
たものである。本発明ドリルビットはＪＩＳ規格の構造
用合金鋼のＳＣＭ４３５で成形された３８φドリルビッ
トに，浸炭雰囲気温度；９３０℃、炉内炭素濃度；０．
５０％で９０分間浸炭したのち、８３０℃に降温し、４
００℃のソルトバス中に焼入れして６０分間保持しその
後空冷した。次に、切刃部先端の溝に超硬チップの両側
に銅サンドインチ銀ロー板を添えて挿入して固定したの
ち、高周波加熱装置によりシャンク部と同時に８５０℃
に加熱して超硬チップをロー付けし、直ちに約８０℃の
オイルパス中に焼入れし、その後２００℃で焼もどし処
理を行ったものである。第４図からわかるように、リー
ド溝部の硬さを切刃部及びシャンク部より低くすること
により、使用時に受ける衝撃を吸収するため，靭性が著
しく向上する。また，第５図により本発明ドリルビット
は硬化層が深いため、摩耗による表面硬さ低下がほとん
どなく、長寿命が得られることがわかる。第６図は本発
明ドリルビットを従来のドリルビットのシャンク部の摩
耗試験結果であり、本結果によれば、従来品はシャンク
部の初期摩耗が大きく，穴明け６２０ケで摩耗量がＩＩ
ＩＩＩ１に達して寿命となるのに対し、本発明品は初期
摩耗が少なく、穴明け１５００ケで摩耗量が１通となり
、約２．４倍の長寿命が得られた。第７図は本発明ドリ
ルビットと従来のドリルビットのコンクリート穴明け数
と切刃部の摩耗寸法及び穴明け速度の関係を示したもの
であり、これより明らかなように、本発明ドリルビット
は切刃部の摩耗量及びコンクリート穴明け速度において
も従来のドリルビットより優れていることがわかる．〔
発明の効果〕
本発明によれば、図６に示したように従来のドリルビッ
トと比較して、シャンク部の摩耗量が少ないので、約２
．４倍の長寿命ドリルビットを得ることができる。Among the above conditions, the most appropriate conditions are: hardness due to hot bath quenching after carburizing; Hv400; surface hardness of the cutting edge and shank; Hv700; hardened layer depth;1.
5mo+, surface carbon concentration during carburizing treatment: 0.50% [Embodiment of the invention] Figure 4 shows the surface hardness and internal hardness distribution in the longitudinal direction of the drill bit of the present invention. FIG. 5 shows the cross-sectional hardness distribution of the shanks of the drill bit of the present invention and the conventional drill bit. The drill bit of the present invention is a 38φ drill bit made of SCM435, a structural alloy steel according to JIS standards, with a carburizing atmosphere temperature of 930°C and a carbon concentration in the furnace of 0.
After carburizing at 50% for 90 minutes, the temperature was lowered to 830°C and 4
It was quenched in a salt bath at 00°C, held for 60 minutes, and then air cooled. Next, a copper sand inch silver solder plate was inserted on both sides of the carbide tip into the groove at the tip of the cutting edge and fixed, and then heated to 850°C at the same time as the shank using a high-frequency heating device.
The carbide tip was brazed by heating to 200°C, immediately quenched in an oil path at about 80°C, and then tempered at 200°C. As can be seen from FIG. 4, by making the hardness of the lead groove portion lower than that of the cutting edge portion and the shank portion, the impact received during use is absorbed, and the toughness is significantly improved. Furthermore, it can be seen from FIG. 5 that since the drill bit of the present invention has a deep hardened layer, there is almost no decrease in surface hardness due to wear, and a long life can be obtained. Figure 6 shows the wear test results of the shank part of the drill bit of the present invention compared to the conventional drill bit.According to the results, the initial wear of the shank part of the conventional drill bit was large, and the amount of wear reached II after drilling 620 holes.
In contrast, the product of the present invention had less initial wear and only one piece of wear was produced after 1,500 holes were drilled, resulting in a life that was about 2.4 times longer. Figure 7 shows the relationship between the number of holes drilled in concrete, the wear dimension of the cutting edge, and the drilling speed of the drill bit of the present invention and the conventional drill bit.As is clear from this, the drill bit of the present invention It can be seen that this drill bit is superior to conventional drill bits in terms of wear on the cutting edge and concrete drilling speed. [
[Effects of the Invention] According to the present invention, as shown in FIG.
．． You can get a drill bit that lasts four times longer.
第１図はドリルビットの全体図であり、第２図はドリル
ビットとハンマードリル本体との嵌合状態を示した断面
図であり、第３図はハンマードリル本体のセカンドハン
マーとドリルビットの嵌合状態の横断面図である。
第４図は本発明になるドリルビットの長さ方向の表面及
び心部の硬さ分布図であり、第５図は本発明になるドリ
ルビットと従来のドリルビットのシャンク部の断面硬さ
分布比較グラフである。第６図は本発明になるドリルビ
ットと従来のドリルビットのコンクリート穴明けによる
シャンク部の摩耗試験結果を示すグラフであり，第７図
は同じくコンクリート穴明け数と切刃部の摩耗量及び穴
明け速度の関係を示したグラフである。
図において、ｌはドリルビットボディ，２は超硬チップ
、３は切刃部、４はリード溝部、５はシャンク部、６は
回転打撃伝達部、７はセカンドハンマー，８はシリンダ
、９はハンマーである。Fig. 1 is an overall view of the drill bit, Fig. 2 is a sectional view showing the fitted state of the drill bit and the hammer drill body, and Fig. 3 is a sectional view showing the fitted state of the drill bit and the second hammer of the hammer drill main body. FIG. FIG. 4 is a hardness distribution diagram of the surface and core in the length direction of the drill bit according to the present invention, and FIG. 5 is a cross-sectional hardness distribution diagram of the shank portion of the drill bit according to the present invention and the conventional drill bit. This is a comparison graph. Figure 6 is a graph showing the wear test results of the shank part of the drill bit of the present invention and the conventional drill bit when drilling concrete holes, and Figure 7 is a graph showing the number of holes drilled in concrete, the amount of wear on the cutting edge, and the hole diameter. It is a graph showing the relationship between dawning speed. In the figure, l is the drill bit body, 2 is the carbide tip, 3 is the cutting edge, 4 is the lead groove, 5 is the shank, 6 is the rotary impact transmission part, 7 is the second hammer, 8 is the cylinder, and 9 is the hammer. It is.
Claims (1)
において、ビットボディ全体を浸炭処理し、その硬さを
Ｈｖ３５０〜５００として靭性を与えたのち、切刃とな
る部分に超硬合金を接合すると同時に、切刃部及びシャ
ンク部を焼入処理したことを特徴とするコンクリート穿
孔用ドリルビットの製造法。 ２、切刃部の超硬合金接合焼入処理とシャンク部の焼入
処理を同時に行い、表面硬さを Ｈｖ６００〜７５０、硬化層深さを１．０ｍｍ以上とし
て、両部所に耐摩耗性を付加したことを特徴とする請求
項１記載のコンクリート穿孔 用ドリルビットの製造法。 ３、浸炭炭素濃度を０．４０〜０．６０％としたことを
特徴とする請求項１記載のコン クリート穿孔用ドリルビットの製造法。[Claims] 1. In a concrete drilling drill bit made of iron-based material, the entire bit body is carburized to give it toughness with a hardness of 350 to 500 Hv, and then the part that will become the cutting edge is made of carbide. A method for manufacturing a drill bit for concrete drilling, characterized in that the cutting edge and shank are hardened at the same time as the alloy is bonded. 2. The cemented carbide joint hardening treatment of the cutting edge part and the hardening treatment of the shank part are performed simultaneously, and the surface hardness is Hv600-750 and the hardened layer depth is 1.0mm or more, making both parts wear resistant. 2. The method for producing a concrete drilling drill bit according to claim 1, further comprising: 3. The method for producing a drill bit for drilling concrete according to claim 1, wherein the carburized carbon concentration is 0.40 to 0.60%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30029689A JPH03161219A (en) | 1989-11-17 | 1989-11-17 | Manufacture of drill bit for concrete boring |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30029689A JPH03161219A (en) | 1989-11-17 | 1989-11-17 | Manufacture of drill bit for concrete boring |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03161219A true JPH03161219A (en) | 1991-07-11 |
Family
ID=17883079
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30029689A Pending JPH03161219A (en) | 1989-11-17 | 1989-11-17 | Manufacture of drill bit for concrete boring |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03161219A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5299441A (en) * | 1991-11-22 | 1994-04-05 | Yugenkaisha Shinjo Seisakusho | Method of making a mandrel comprising a drill section for a self-drilling blind rivet |
-
1989
- 1989-11-17 JP JP30029689A patent/JPH03161219A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5299441A (en) * | 1991-11-22 | 1994-04-05 | Yugenkaisha Shinjo Seisakusho | Method of making a mandrel comprising a drill section for a self-drilling blind rivet |
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