CN110259389B - Preparation method of rolling gauge protection drill bit - Google Patents
Preparation method of rolling gauge protection drill bit Download PDFInfo
- Publication number
- CN110259389B CN110259389B CN201910599575.2A CN201910599575A CN110259389B CN 110259389 B CN110259389 B CN 110259389B CN 201910599575 A CN201910599575 A CN 201910599575A CN 110259389 B CN110259389 B CN 110259389B
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- China
- Prior art keywords
- positioning
- drill bit
- ball
- hoop
- mounting groove
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- 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.)
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/42—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits
- E21B10/43—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits characterised by the arrangement of teeth or other cutting elements
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
Abstract
The invention discloses a rolling gauge protection drill bit which comprises a drill bit main body, wherein the drill bit main body comprises a blade, the blade comprises a gauge protection part, a mounting groove is formed in the gauge protection part, a ball is arranged in the mounting groove and is in rolling connection with the mounting groove, cutting teeth are fixedly arranged on the gauge protection part, the rotating direction of the drill bit is taken as the positive direction, the cutting teeth are arranged at the front part of the gauge protection part, the ball is arranged at the rear part of the cutting teeth, and the ball is partially protruded outside the gauge protection part. The rolling direction of the ball can be changed at any time, and no matter when the drill bit turns or the drilling rate changes, the ball can both reduce the frictional force of gauge and the wall of a well through the form of rolling, improves drilling efficiency.
Description
Technical Field
The invention relates to the field of petroleum drilling equipment, in particular to a preparation method of a rolling gauge protection drill bit.
Background
The friction force in the drilling process is reduced, the drilling efficiency is improved, the friction coefficient of the diameter-protecting part and the well wall or the contact area of the diameter-protecting part and the well wall can be reduced, and because the diameter-protecting part needs to play a role in compacting the well wall, the contact area of the diameter-protecting part and the well wall cannot be too small, otherwise, the diameter-protecting function becomes a cutting function, and the diameter-protecting effect is reduced. Is a design difficulty of the gauge. The prior art proposes to arrange a roller on the gauge to reduce the friction coefficient between the gauge and the well wall. For example, chinese patent CN 201310126849.9-a device for correcting the borehole wall enhanced bit gauge protection effect by using rolling action, and chinese patent cn201620853605.x rolling gauge protection PDC bit, both propose similar structures of arranging rollers on gauge protection parts. The chinese patent cn201620853605.x rolling gauge-keeping PDC drill bit also adopts a roller to keep gauge in the disclosed structure, wherein a recess is provided on the gauge-keeping section of each blade, a roller assembly is installed in the recess, the roller assembly is provided with a rolling shaft, and the rolling shaft is fixedly connected with the drill bit body so as to combine the roller assembly and the drill bit body into a rolling gauge-keeping structure.
However, the practical application is very rare because the gauge of the roller or the roller has large defects. The problems that the number of parts is large, the connection relation is complex, the using environment of the drill bit is severe, vibration and extrusion are large in the using process, and the parts related to the roller are easy to damage are caused; when the drill bit is used, the rotating shaft is very large in extrusion acting force and easy to deform, and the rotating shaft is easy to bend and damage due to vibration.
Further, since the roller receives a large frictional force in the same direction as the extending direction of the rotary shaft, the point on the surface of the drill not only rotates along the drill but also travels together with the drill, and therefore, the actual movement locus of the point on the surface of the drill is spiral, and the speed of the drill changes depending on the hardness of the geology, and therefore, the pitch of the actual movement locus of the point on the surface of the drill is not uniform, the roller receives a frictional force of the wall of the well in the extending direction of the shaft of the roller, the end surface of the roller is in close contact with the groove in which the roller is installed and continuously rubs against the groove wall, and the roller does not receive a large frictional force to the diameter reducing portion.
This configuration has been rarely used in practice because of the above disadvantages of using rollers to reduce friction between the gauge and the borehole wall.
In the prior art, most gauge protection parts are provided with gauge protection teeth and back-reaming holes, and the gauge protection teeth are used for cutting a well wall, so that the friction between the gauge protection teeth and the well wall is large, the reduction of the drilling efficiency is obvious, and a new mode for reducing the friction between a gauge protection part and the well wall is very necessary.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the rolling gauge protection drill bit is high in strength, not prone to damage and beneficial to improving drilling efficiency.
The solution of the invention for solving the technical problem is as follows:
the utility model provides a roll gauge bit, includes the drill bit main part, the drill bit main part includes the wing, the wing includes the gauge portion, be equipped with the mounting groove in the gauge portion, be equipped with the ball in the mounting groove, the ball with mounting groove roll connection, the last cutting teeth that has still set firmly of gauge portion to the direction of rotation of drill bit is the positive direction, the cutting teeth is located the front portion of gauge portion, the ball is located the cutting teeth rear, the ball part is protruding outside the gauge portion.
The ball bearing is fixedly connected with the mounting groove, and a gap is formed between the ball bearing and the wall surface of the mounting groove.
Furthermore, the positioning holes are 1/3-1/5 spherical.
Rotatable ground, the location hoop includes spacer, lower spacer, the ball is located go up the spacer with between the spacer down, go up the spacer, all be equipped with the locating hole between the spacer down.
Further, the positioning device also comprises a retaining block, and the retaining block is arranged between the adjacent upper positioning piece and the lower positioning piece.
Optionally, the positioning hoop further comprises a middle positioning plate, and positioning holes are formed in the top surface and the bottom surface of the middle positioning plate between the upper positioning plate and the lower positioning plate.
Further, the positioning device also comprises a holding block, wherein the holding block is arranged between the adjacent upper positioning sheets and the adjacent middle positioning sheets, or the holding block is arranged between the adjacent lower positioning sheets and the adjacent middle positioning sheets.
Further, the retaining block is in splined engagement with the retaining band.
Optionally, the front side and the rear side of location hoop with all be equipped with the welding clearance between the mounting groove, the location hoop with the mounting groove welding links to each other, still includes the gasket, the gasket is located the hoop of location with between the mounting groove, the gasket is located the top or the below of location hoop.
A preparation method of a rolling gauge bit is used for preparing the rolling gauge bit and comprises the following steps: s1, casting the drill bit main body, and casting a mounting groove; s2, sand blasting is carried out on the drill bit main body; s3, mounting a positioning hoop, a ball and a retaining block into the mounting groove, and inserting the gasket between the positioning hoop and the mounting groove; s4, heating the drill bit main body to 480-520 ℃, and then placing the drill bit main body on a welding operation table; s5, welding the positioning hoop and the holding block with the mounting groove; s6, welding the surface of the blade wing; s7, placing the blank in a heat preservation box, keeping the temperature constant for 1 hour, and slowly cooling for more than 4 hours; and S8, welding the polycrystalline diamond cutting tooth.
The invention has the beneficial effects that: the rolling direction of the ball can be changed at any time, and no matter when the drill bit turns or the drilling rate changes, the ball can both reduce the frictional force of gauge and the wall of a well through the form of rolling, improves drilling efficiency.
Drawings
In order to more clearly illustrate the technical solution in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is clear that the described figures are only some embodiments of the invention, not all embodiments, and that a person skilled in the art can also derive other designs and figures from them without inventive effort.
FIG. 1 is a schematic view of the present invention;
FIG. 2 is a schematic view of a bit body of the present invention;
FIG. 3 is a schematic illustration of a partial explosion of the present invention;
FIG. 4 is one of the enlarged partial views of the present invention;
fig. 5 is a second partial enlarged view of the present invention.
Detailed Description
Referring to fig. 1 to 5, this is an embodiment of the invention, specifically:
the utility model provides a roll gauge bit, includes drill bit main part 1, drill bit main part 1 includes the blade, the blade includes gauge part 2, be equipped with mounting groove 21 on the gauge part 2, be equipped with ball 3 in the mounting groove 21, ball 3 with mounting groove 21 roll connection, cutting teeth 4 has still set firmly on the gauge part 2 to the direction of rotation of drill bit is the positive direction, cutting teeth 4 locates the front portion of gauge part 2, ball 3 locates cutting teeth 4 rear, ball 3 part is protruding outside gauge part 2. Preferably, the highest point of the ball 3 is not higher than the highest point of the cutting tooth 4. The cutting teeth 4 play a role in cutting and trimming the well wall, the gauge protection part 2 plays a role in compacting the gauge protection of the well wall, the ball 3 connected with the gauge protection part 2 in a rolling manner is arranged on the gauge protection part 2, the ball 3 rolls on the well wall in the process that a drill bit rotates in the positive direction and advances forwards, the rolling path is spiral, the rolling direction of the ball 3 can be changed at any time, and the ball 3 can pass through the rolling manner when the drill bit turns or the drilling speed is changed, so that the friction force between the gauge protection part and the well wall is reduced, and the drilling efficiency is improved.
Further, the positioning device further comprises a positioning hoop 5, a positioning hole 51 is formed in the positioning hoop 5, the ball 3 is arranged in the positioning hole 51, and the positioning hoop 5 is fixedly connected with the mounting groove 21. Preferably, the distance between the ball 3 and the wall surface of the mounting groove 21 is 0.05-2 mm. The position of the ball 3 is determined by the positioning hole 51, the ball 3 is not contacted with the wall surface of the mounting groove 21, when in processing, the ball can roll smoothly only by ensuring the surface roughness of the ball 3 and the surface roughness of the positioning hole 51, the positioning hole 51 which is processed smoothly on the positioning hoop 5 is easier than the positioning hole which is processed smoothly in the mounting groove, and the precision of the diameter of the positioning hole 51 is conveniently ensured.
Furthermore, the positioning holes 51 are 1/3-1/5 spheres. Even if the surface of the positioning collar is worn to a certain extent so that the positioning hole 51 becomes shallow, the positioning hole 51 can restrain the ball 3 in the positioning hole as long as the deepest vicinity of the positioning hole 51 is still covered outside the ball 3. Preferably, the diameter of the positioning hole 51 is 0.05-0.5 mm larger than the diameter of the ball 3.
Optionally, the positioning hoop 5 includes an upper positioning plate 52 and a lower positioning plate 53, the ball 3 is disposed between the upper positioning plate 52 and the lower positioning plate 53, and the positioning hole 51 is disposed between the upper positioning plate 52 and the lower positioning plate 53. Set the location hoop 5 into spacer 52 and spacer 53 down, can be easy to assemble ball 3, during the installation, can arrange lower spacer 52 in mounting groove 21 earlier, arrange ball 3 in locating hole 51 again, at last with last spacer 53 embedding mounting groove 21 in, and push last spacer 53 to the position that is close to ball 3, can form the clearance between the last wall of last spacer 53 and mounting groove 21, this clearance can be used to weld spacer 53 and mounting groove 21.
Further, the positioning device further comprises a retaining block 6, and the retaining block 6 is arranged between the adjacent upper positioning sheets 52 and the adjacent lower positioning sheets 53. In order to accurately ensure the gap between the ball 3 and the positioning hole 51, the retaining block 6 may be provided to control the gap between the upper positioning plate 52 and the lower positioning plate 53 in such a manner that the height of the retaining block 6 is controlled and both ends of the retaining block 6 abut against the upper positioning plate 52 and the lower positioning plate 53, so that the distance between the upper positioning plate and the lower positioning plate in the positioning hole 51 can be controlled, and the accuracy of the gap between the ball 3 and the positioning hole 51 is also ensured.
In some embodiments, the positioning hoop 5 further comprises a middle positioning plate 54, the top surface and the bottom surface of the middle positioning plate 54 are provided with positioning holes 51, and the middle positioning plate 54 is disposed between the upper positioning plate 52 and the lower positioning plate 53. The positioning piece 54 can increase the position for installing the ball 3.
Further, the positioning device further comprises a retaining block 6, wherein the retaining block 6 is arranged between the adjacent upper positioning sheets 52 and the adjacent middle positioning sheets 54, or the retaining block 6 is arranged between the adjacent lower positioning sheets 53 and the adjacent middle positioning sheets 54.
Further, the holding block 6 is spline-connected to the positioning band 5. By adopting the key way connection mode, the transverse freedom degree of the holding block 6 can be limited, and a gap is formed at the joint of the holding block 6 and the positioning hoop 5, so that the area available for welding is increased, and the strength is increased.
In some embodiments, welding gaps are respectively provided between the front side and the rear side of the positioning hoop 5 and the mounting groove 21, the positioning hoop 5 is connected to the mounting groove 21 by welding, the positioning hoop further comprises a gasket 7, the gasket 7 is provided between the positioning hoop and the mounting groove 21, and the gasket 7 is provided above or below the positioning hoop 5. The arrangement of the broken stone welding gap is beneficial to convenient installation of the ball and the positioning hoop, and the gasket 7 is used for controlling the welding gap and avoiding the overlarge welding gap.
A preparation method of a rolling gauge bit is used for preparing the rolling gauge bit and comprises the following steps: s1, casting the drill bit main body 1, and casting the mounting groove 21; s2, sand blasting is carried out on the drill bit body 1; s3, installing the positioning hoop 5, the ball 3 and the retaining block 6 into the installation groove 21, and inserting the gasket 7 between the positioning hoop 5 and the installation groove 21; s4, heating the drill bit main body 1 to 480-520 ℃, and then placing the drill bit main body on a welding operation table; s5, welding the positioning hoop 5 and the holding block 6 with the mounting groove 21; s6, welding the surface of the blade wing; s7, placing the blank in a heat preservation box, keeping the temperature constant for 1 hour, and slowly cooling for more than 4 hours; and S8, welding the polycrystalline diamond cutter 4.
In the description of the present invention, it is to be understood that the terms "length", "upper", "lower", "top", "bottom", "inner", "outer", "circumferential", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and simplification of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims (7)
1. A preparation method of a rolling gauge protection drill bit is characterized by comprising the following steps: the method is used for preparing the rolling gauge protection drill bit;
the rolling gauge protection drill bit comprises a drill bit main body (1), wherein the drill bit main body (1) comprises a blade, the blade comprises a gauge protection part (2), a mounting groove (21) is formed in the gauge protection part (2), a ball (3) is arranged in the mounting groove (21), the ball (3) is in rolling connection with the mounting groove (21), cutting teeth (4) are further fixedly arranged on the gauge protection part (2), the rotating direction of the drill bit is the positive direction, the cutting teeth (4) are arranged at the front part of the gauge protection part (2), the ball (3) is arranged at the rear part of the cutting teeth (4), and the ball (3) is partially protruded outside the gauge protection part (2); the rolling gauge protection drill bit further comprises a positioning hoop (5), a positioning hole (51) is formed in the positioning hoop (5), the ball (3) is arranged in the positioning hole (51), the positioning hoop (5) is fixedly connected with the mounting groove (21), and a gap is formed between the ball (3) and the wall surface of the mounting groove (21); the leading flank and the trailing flank of location hoop (5) with all be equipped with weld gap between mounting groove (21), location hoop (5) with mounting groove (21) welding links to each other, still includes gasket (7), gasket (7) are located hoop of location with between mounting groove (21), gasket (7) are located the top or the below of hoop (5) are located in the location:
the method comprises the following steps:
s1, casting the drill bit main body (1) and casting a mounting groove (21);
s2, carrying out sand blasting on the drill bit main body (1);
s3, installing the positioning hoop (5), the ball (3) and the retaining block (6) into the installation groove (21), and inserting the gasket (7) between the positioning hoop (5) and the installation groove (21);
s4, heating the drill bit main body (1) to 480-520 ℃, and then placing the drill bit main body on a welding operation table;
s5, welding the positioning hoop (5) and the retaining block (6) with the mounting groove (21);
s6, welding the surface of the blade wing;
s7, placing the blank in a heat preservation box, keeping the temperature constant for 1 hour, and slowly cooling for more than 4 hours;
and S8, welding the polycrystalline diamond cutting tooth (4).
2. The method of making a rolling gage drill bit as defined in claim 1, wherein: the positioning holes (51) are 1/3-1/5 spheres.
3. The method of making a rolling gage drill bit as defined in claim 1, wherein: the positioning hoop (5) comprises an upper positioning sheet (52) and a lower positioning sheet (53), the ball (3) is arranged between the upper positioning sheet (52) and the lower positioning sheet (53), and positioning holes (51) are formed between the upper positioning sheet (52) and the lower positioning sheet (53).
4. The method of making a rolling gage drill bit as defined in claim 3, wherein: the positioning device also comprises a retaining block (6), wherein the retaining block (6) is arranged between the adjacent upper positioning sheets (52) and the lower positioning sheets (53).
5. The method of making a rolling gage drill bit as defined in claim 3, wherein: the positioning hoop (5) further comprises a middle positioning sheet (54), the middle positioning sheet (54) is arranged between the upper positioning sheet (52) and the lower positioning sheet (53), and positioning holes (51) are formed in the top surface and the bottom surface of the middle positioning sheet (54).
6. The method of making a rolling gage drill bit as defined in claim 5, wherein: the positioning device further comprises a retaining block (6), wherein the retaining block (6) is arranged between the adjacent upper positioning sheets (52) and the adjacent middle positioning sheets (54), or the retaining block (6) is arranged between the adjacent lower positioning sheets (53) and the adjacent middle positioning sheets (54).
7. The method of making a rolling gage drill bit as defined in claim 6, wherein: the holding block (6) is in keyway connection with the positioning hoop (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910599575.2A CN110259389B (en) | 2019-07-04 | 2019-07-04 | Preparation method of rolling gauge protection drill bit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910599575.2A CN110259389B (en) | 2019-07-04 | 2019-07-04 | Preparation method of rolling gauge protection drill bit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110259389A CN110259389A (en) | 2019-09-20 |
| CN110259389B true CN110259389B (en) | 2021-01-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910599575.2A Active CN110259389B (en) | 2019-07-04 | 2019-07-04 | Preparation method of rolling gauge protection drill bit |
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| CN (1) | CN110259389B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112392405B (en) * | 2020-12-28 | 2022-06-21 | 西南石油大学 | Special drill bit of reverse circulation well drilling |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201671547U (en) * | 2010-05-06 | 2010-12-15 | 中国石油天然气股份有限公司 | PDC drill with gauge having cylinder roller |
| CN203308383U (en) * | 2013-04-12 | 2013-11-27 | 成都保瑞特钻头有限公司 | Device for amending well wall and improving drill bit gauge protection effect through action of rolling |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7836792B2 (en) * | 2008-09-25 | 2010-11-23 | Baker Hughes Incorporated | System, method and apparatus for enhanced cutting element retention and support in a rock bit |
| WO2011017673A2 (en) * | 2009-08-07 | 2011-02-10 | Smith International, Inc. | Thermally stable polycrystalline diamond constructions |
| CN203547549U (en) * | 2013-11-18 | 2014-04-16 | 成都百施特金刚石钻头有限公司 | Spin type pdc drill bit |
| CN205895148U (en) * | 2016-08-09 | 2017-01-18 | 武汉亿斯达工具有限公司 | Roll and protect footpath PDC drill bit |
| CN207829819U (en) * | 2018-02-10 | 2018-09-07 | 西南石油大学 | A kind of low torque diamond bit suitable for hard formation drilling |
| CN208106331U (en) * | 2018-02-10 | 2018-11-16 | 西南石油大学 | Combined type diamond bit with slew buffer structure |
| CN208633779U (en) * | 2018-08-21 | 2019-03-22 | 立府精密机械有限公司 | A kind of diamond compact bit |
-
2019
- 2019-07-04 CN CN201910599575.2A patent/CN110259389B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201671547U (en) * | 2010-05-06 | 2010-12-15 | 中国石油天然气股份有限公司 | PDC drill with gauge having cylinder roller |
| CN203308383U (en) * | 2013-04-12 | 2013-11-27 | 成都保瑞特钻头有限公司 | Device for amending well wall and improving drill bit gauge protection effect through action of rolling |
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| Publication number | Publication date |
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| CN110259389A (en) | 2019-09-20 |
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Effective date of registration: 20220418 Address after: 300000 next to the bus stop of Lilin group, Fukang Road, Sanhe Village, gegu Town, Jinnan District, Tianjin Patentee after: TIANJIN LILIN BIT Co.,Ltd. Address before: 618300 East 2nd section of Zhuhai Road, Guanghan Economic Development Zone, Deyang City, Sichuan Province Patentee before: LIFU PRECISION MACHINERY Co.,Ltd. |