CN113878135B - Boring processing method for ultra-long hole of special-shaped part - Google Patents
Boring processing method for ultra-long hole of special-shaped part Download PDFInfo
- Publication number
- CN113878135B CN113878135B CN202111183701.XA CN202111183701A CN113878135B CN 113878135 B CN113878135 B CN 113878135B CN 202111183701 A CN202111183701 A CN 202111183701A CN 113878135 B CN113878135 B CN 113878135B
- Authority
- CN
- China
- Prior art keywords
- boring
- guide bushing
- phi
- hole
- cutter bar
- 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.)
- Active
Links
- 238000003672 processing method Methods 0.000 title claims abstract description 11
- 238000005553 drilling Methods 0.000 claims abstract description 41
- 238000000034 method Methods 0.000 claims abstract description 35
- 238000003754 machining Methods 0.000 claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 claims abstract description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 16
- 229910052742 iron Inorganic materials 0.000 claims description 8
- 238000003860 storage Methods 0.000 claims description 8
- 238000001816 cooling Methods 0.000 claims description 7
- 229910001369 Brass Inorganic materials 0.000 claims description 4
- 229910001018 Cast iron Inorganic materials 0.000 claims description 4
- 239000010951 brass Substances 0.000 claims description 4
- 230000001050 lubricating effect Effects 0.000 claims description 4
- 210000001503 joint Anatomy 0.000 claims description 3
- 239000011148 porous material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B35/00—Methods for boring or drilling, or for working essentially requiring the use of boring or drilling machines; Use of auxiliary equipment in connection with such methods
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B29/00—Holders for non-rotary cutting tools; Boring bars or boring heads; Accessories for tool holders
- B23B29/02—Boring bars
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B41/00—Boring or drilling machines or devices specially adapted for particular work; Accessories specially adapted therefor
- B23B41/02—Boring or drilling machines or devices specially adapted for particular work; Accessories specially adapted therefor for boring deep holes; Trepanning, e.g. of gun or rifle barrels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B49/00—Measuring or gauging equipment on boring machines for positioning or guiding the drill; Devices for indicating failure of drills during boring; Centering devices for holes to be bored
- B23B49/02—Boring templates or bushings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B51/00—Tools for drilling machines
- B23B51/06—Drills with lubricating or cooling equipment
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Abstract
The invention provides a boring processing method for an ultra-long hole of a special-shaped part, which comprises the following steps: step one: pre-drilling holes; step two: establishing a process hole; step three: manufacturing a special cutter bar; step four: manufacturing a guide bushing; step five: boring. The machining method finishes boring the long hole by adopting the method of boring the cutter bar and the sliding bush special for design by utilizing the advantages of the numerical control machine tool and the application of new cutters and turning around the machining, thereby achieving the purposes of improving the machining efficiency and reducing the machining cost.
Description
Technical Field
The invention relates to a boring processing method for an ultra-long hole of a special-shaped part, and belongs to the technical field of deep hole processing.
Background
In the processing process of a bearing seat long hole of a certain company, the part is a cuboid with the processing content of 1700 multiplied by 990 multiplied by 350cm, the processing content is mainly concentrated in the pre-welding processing of various oil holes, pipeline holes, pipe threads and bearing holes, the processing precision requirement is not high, but the processing difficulty is very high, the most difficult processing is the processing of a long hole with the diameter of 130 multiplied by 1700cm, and the deep hole drilling machine cannot process due to the irregular appearance and can only be completed on a boring machine. To finish machining the phi 130 hole, a common boring machine is divided into a plurality of steps of drilling, expanding and boring, and boring process is also required to be replaced with boring cutter bars with different specification lengths for sectional machining, which is time-consuming and labor-consuming.
Disclosure of Invention
The invention aims to provide a boring processing method for an ultra-long hole of a special-shaped part, which is used for completing boring processing of a long hole by adopting a special boring cutter bar and a sliding bush by designing a turning processing method by utilizing the advantages of a numerical control machine tool and the application of a new cutter, thereby achieving the purposes of improving the processing efficiency and reducing the processing cost.
In order to achieve the technical characteristics, the aim of the invention is realized in the following way: the boring processing method of the ultra-long hole of the special-shaped part comprises the following steps:
step one: pre-drilling holes;
step two: establishing a process hole;
step three: manufacturing a special cutter bar;
step four: manufacturing a guide bushing;
step five: boring.
The specific operation process of the first step is that a numerical control boring machine with a rotary table is selected for processing parts, and a large-diameter deep hole drill is selected; and (3) drilling one end of the part by using a numerical control boring machine, turning around the part by using a rotary table after the part is machined to a certain depth, and drilling the other end of the part, thereby completing the pre-drilling of the part.
The selected numerical control boring machine is an in-band cooling boring machine;
the large-diameter deep hole drill is a high-speed super large-diameter deep hole drill;
drilling line speed V c ≥100m/min；
The maximum depth of the unidirectional drilling of the pre-drilling hole is 700cm;
the pore diameter phi B of the pre-drilled hole is smaller than the pore diameter phi A of the standard hole to be processed.
The specific operation process of the second step is that process holes are established at two ends of the pre-drilled hole in the first step, wherein the diameter size of the process holes is controlled to be phi A+0.1, the process holes are deeply processed to be 500cm, and the front and back sizes are consistent and are used for supporting the supporting guide sleeve in the follow-up boring operation.
The special cutter bar in the third step adopts a cutter bar joint module with the diameter phi B and the same diameter as that of the large-diameter deep hole drill; the cutter bar joint module is used for lengthening the large-diameter deep hole drill to phi B multiplied by 900cm, and the original large-diameter deep hole drill is in butt joint with the cutter bar joint module; and then drilling the two ends of the pre-drilling hole continuously until the pre-drilling holes at the two ends are drilled through, so that scrap iron is discharged during subsequent boring.
The guide bushing in the fourth step is used for supporting the boring cutter bar; the inner diameter phi C of the guide bushing is equal to the outer diameter phi D of the boring cutter bar, and the outer diameter of the guide bushing is equal to the aperture phi A of the standard hole.
The inner diameter phi C of the guide bushing is controlled to be phi C+0.2; the outer diameter of the boring cutter bar is controlled to be phi C+0.1; and the outer diameter of the guide bushing is controlled to be phi A-0.1.
The inner hole of the guide bushing is provided with two annular oil storage cavities, the inner wall of the guide bushing is connected with the oil storage cavities at 120-degree positions through three grooves, a lubricating effect is achieved, friction force between the cutter bar and the guide bushing is reduced, and QT400 cast iron or brass is selected as a guide bushing material.
In the fifth step, the boring cutter bar is supported by the guide bushing, the guide bushing can slide freely in the hole, scrap iron is smoothly discharged from the rear during boring, and sectional machining is adopted.
The invention has the following beneficial effects:
1. according to the invention, the high-efficiency large-diameter internal cooling drill bit is adopted for drilling, the cutting parameter S=300/F=30 of the cutter is adopted, the machining efficiency of machining one hole is only 25-30 minutes, which is more than 10 times that of a common drill bit, and through the design of a simple and reasonable boring cutter bar and a guide bushing tool, the boring of a long hole is completed by turning around by establishing a process hole, the method is simple and easy to operate, and the machining process is stable and reliable, so that the machining difficulty of the long hole of a special-shaped part is effectively solved.
2. According to the invention, the boring processing of the long hole is completed by utilizing the advantages of the numerical control machine tool and the application of a new tool and by designing the special boring cutter bar and the sliding bush and turning around the processing method, so that the purposes of improving the processing efficiency and reducing the processing cost are achieved.
3. By adopting the processing method, the invention solves the problems of high processing difficulty and low efficiency on the common boring and milling machine, is convenient to operate and has higher efficiency.
Drawings
The invention is further described below with reference to the drawings and examples.
Fig. 1 is a front view of a part to be machined in accordance with the present invention.
Fig. 2 is a side view of a part to be machined in accordance with the present invention.
Fig. 3 is a front view of the present invention for completing processing of a process hole.
Fig. 4 is a block diagram of a tool bar joint module according to the present invention.
Fig. 5 is a front cross-sectional view of the guide bushing of the present invention.
Fig. 6 is a left cross-sectional view of the guide bushing of the present invention.
Fig. 7 is a block diagram of a boring bar according to the present invention.
FIG. 8 is a schematic diagram of the boring process of the present invention.
Detailed Description
Embodiments of the present invention will be further described with reference to the accompanying drawings.
Referring to fig. 1-8, the boring processing method for the ultra-long hole of the special-shaped part comprises the following steps:
step one: pre-drilling holes;
step two: establishing a process hole;
step three: manufacturing a special cutter bar;
step four: manufacturing a guide bushing;
step five: boring.
Further, the specific operation process of the first step is that a numerical control boring machine with a rotary table is selected for processing parts, and a large-diameter deep hole drill is selected; and (3) drilling one end of the part by using a numerical control boring machine, turning around the part by using a rotary table after the part is machined to a certain depth, and drilling the other end of the part, thereby completing the pre-drilling of the part.
Further, the selected numerical control boring machine is an in-band cooling boring machine; the internal cooling boring machine has a certain cooling effect.
Furthermore, the large-diameter deep hole drill is a high-Mic large-diameter deep hole drill;
further, the drilling line speed V c Not less than 100m/min; by adopting the drilling speed, the drilling efficiency is effectively improved.
Further, the maximum depth of the unidirectional drilling of the pre-drilling hole is 700cm;
further, the pore diameter Φb of the pre-drilled hole is smaller than the pore diameter Φa of the standard hole to be processed.
Furthermore, the specific operation process of the second step is that process holes are established at two ends of the pre-drilled hole in the first step, wherein the diameter size of the process holes is controlled to be phi A+0.1, the process holes are deeply processed to be 500cm, and the front and back sizes are consistent and are used for supporting the supporting guide sleeve in the subsequent boring operation.
Furthermore, the special cutter bar in the third step adopts a cutter bar joint module with the diameter phi B and the same diameter as that of the large-diameter deep hole drill; the cutter bar joint module is used for lengthening the large-diameter deep hole drill to phi B multiplied by 900cm, and the original large-diameter deep hole drill is in butt joint with the cutter bar joint module; and then drilling the two ends of the pre-drilling hole continuously until the pre-drilling holes at the two ends are drilled through, so that scrap iron is discharged during subsequent boring.
Further, the guide bushing in the fourth step is used for supporting the boring cutter bar; the inner diameter phi C of the guide bushing is equal to the outer diameter phi D of the boring cutter bar, and the outer diameter of the guide bushing is equal to the aperture phi A of the standard hole.
Further, the inner diameter phi C of the guide bushing is controlled to be phi C+0.2; the outer diameter of the boring cutter bar is controlled to be phi C+0.1; and the outer diameter of the guide bushing is controlled to be phi A-0.1.
Furthermore, the inner hole of the guide bushing is provided with two annular oil storage cavities, the inner wall is connected with the oil storage cavities at 120-degree positions through three grooves, a lubricating effect is achieved, friction between the cutter bar and the guide bushing is reduced, and QT400 cast iron or brass is selected as the guide bushing.
In the fifth step, the boring bar is supported by the guide bushing, the guide bushing is enabled to slide freely in the hole, scrap iron is smoothly discharged from the rear during boring, and sectional machining is adopted.
Example 2:
the technical scheme of the invention is that deep hole processing is completed through the steps of pre-drilling, establishing a process hole, manufacturing a special cutter bar, manufacturing a guide bushing and boring.
Step one: pre-drilling.
Because the part is of a cuboid structure, the size of the part reaches 1700cm multiplied by 990cm, and the required processing phi 130 is longThe hole is parallel to the length direction, because the length of the part is too long, the numerical control boring machine with internal cooling is selected, the deep hole with the large diameter is drilled on the boring machine by the high-speed super-large diameter and the pre-drilling is finished by turning around the rotary worktable, and the cutter has the advantages of large diameter of one-time drilling and high linear velocity V of drilling c And the machining efficiency is high, wherein the machining speed is more than or equal to 100 m/min.
Step two: and (5) establishing a process hole.
In order to facilitate the use of the subsequent boring support guide bushing, process holes are required to be established at two ends of the phi 130 hole, the diameter size of the hole is controlled to be phi 130+0.1, the depth is processed to be 500cm, the front and back sizes are consistent, and the guide bushing is used for support.
Step three: and manufacturing a special cutter bar.
And a 200mm constant diameter module is used for lengthening a large-diameter deep hole with phi of 110 multiplied by 700 to phi of 110 multiplied by 900, two drilling ends are continued, 1700-size drilling is carried out, and scrap iron is conveniently discharged during subsequent boring.
Step four: and manufacturing a guide bushing.
Because the hole is too long, the U-turn boring cutter bar overhangs by 1.2 meters and cannot be used normally, and the cutter bar must be added with a guide bushing. A BT50 handle is designed, a boring cutter rod with the length phi 90 minus 0.1 multiplied by 1200cm is designed, the inner diameter of a guide bushing is matched with the size phi 90 plus 0.2 according to the outer diameter of the cutter rod, the outer diameter of the bushing is matched with the size phi 130-0.1 according to the size of a machining hole, a certain gap is reserved, two annular oil storage cavities are arranged in the inner hole of the bushing, three grooves in the 120-degree position of the inner wall are connected with the oil storage cavities, a good lubricating effect can be achieved, the friction force between the cutter rod and the bushing is reduced, and QT400 cast iron or brass is selected as a bushing material.
Step five: boring.
The boring processing is supported by the guide bushing, and the welding cutter is adopted, so that a large cutter draft can be ensured, the single side is 5mm, the cutting vibration of the cutter is effectively eliminated, and the processing process is more stable. The scrap iron is smoothly discharged from the back when the hole is drilled, so that the continuity of the hole is improved, the processing process is stable, and the processing efficiency is obviously improved due to the adoption of sectional processing.
Claims (2)
1. The boring processing method for the ultra-long hole of the special-shaped part is characterized by comprising the following steps of:
step one: pre-drilling holes;
step two: establishing a process hole;
step three: manufacturing a special cutter bar;
step four: manufacturing a guide bushing;
step five: boring;
the specific operation process of the first step is that a numerical control boring machine with a rotary table is selected for processing parts, and a large-diameter deep hole drill is selected; drilling one end of the part by a numerical control boring machine, turning around the part by using a rotary table after the part is machined to a certain depth, and drilling the other end of the part to finish pre-drilling of the part;
the selected numerical control boring machine is an in-band cooling boring machine;
the large-diameter deep hole drill is a high-speed super large-diameter deep hole drill;
drilling line speed V c ≥100m/min；
The maximum depth of the unidirectional drilling of the pre-drilling hole is 700cm;
the aperture phi B of the pre-drilled hole is smaller than the aperture phi A of the standard hole to be processed;
the specific operation process of the second step is that process holes are established at two ends of the pre-drilled hole in the first step, wherein the diameter size of the process holes is controlled to be phi A+0.1, the process holes are deeply processed to 500cm, and the front and back sizes are consistent and are used for supporting the supporting guide sleeve in the subsequent boring operation;
the special cutter bar in the third step adopts a cutter bar joint module with the diameter phi B and the same diameter as that of the large-diameter deep hole drill; the cutter bar joint module is used for lengthening the large-diameter deep hole drill to phi B multiplied by 900cm, and the original large-diameter deep hole drill is in butt joint with the cutter bar joint module; drilling the two ends of the pre-drilled hole continuously until the pre-drilled holes at the two ends are drilled through, so that scrap iron is discharged during subsequent boring;
the guide bushing in the fourth step is used for supporting the boring cutter bar; the inner diameter phi C of the guide bushing is equal to the outer diameter phi D of the boring cutter bar, and the outer diameter of the guide bushing is equal to the aperture phi A of the standard hole;
the inner hole of the guide bushing is provided with two annular oil storage cavities, the inner wall of the guide bushing is connected with the oil storage cavities at the position of 120 degrees, so that the guide bushing has a lubricating effect, the friction force between the cutter bar and the guide bushing is reduced, and the guide bushing is made of QT400 cast iron or brass;
in the fifth step, the boring cutter bar is supported by the guide bushing, the guide bushing can slide freely in the hole, scrap iron is smoothly discharged from the rear during boring, and sectional machining is adopted.
2. The method for boring the ultra-long hole of the special-shaped part according to claim 1, wherein the method comprises the following steps: the inner diameter phi C of the guide bushing is controlled to be phi C+0.2; the outer diameter of the boring cutter bar is controlled to be phi C+0.1; and the outer diameter of the guide bushing is controlled to be phi A-0.1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111183701.XA CN113878135B (en) | 2021-10-11 | 2021-10-11 | Boring processing method for ultra-long hole of special-shaped part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111183701.XA CN113878135B (en) | 2021-10-11 | 2021-10-11 | Boring processing method for ultra-long hole of special-shaped part |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113878135A CN113878135A (en) | 2022-01-04 |
| CN113878135B true CN113878135B (en) | 2024-03-29 |
Family
ID=79006094
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111183701.XA Active CN113878135B (en) | 2021-10-11 | 2021-10-11 | Boring processing method for ultra-long hole of special-shaped part |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113878135B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1593788A1 (en) * | 1987-11-16 | 1990-09-23 | Ленинградский механический институт им.Маршала Советского Союза Устинова Д.Ф. | Method and apparatus for working deep holes |
| CN103028752A (en) * | 2012-11-28 | 2013-04-10 | 湖北三环锻压设备有限公司 | Processing method for phi 52H7*850 deep hinge pin keyhole at matched position of parts of different materials |
| CN104625152A (en) * | 2014-12-02 | 2015-05-20 | 李连江 | Method for machining deep hole of long-cylinder part |
| CN107598204A (en) * | 2017-10-10 | 2018-01-19 | 上海第机床厂有限公司 | The deep hole processing method of CRDM drive rod |
| CN108115176A (en) * | 2017-12-18 | 2018-06-05 | 航天科工哈尔滨风华有限公司 | A kind of high-precision step shaft titanium alloy material Fine and Deep Hole high-efficiency machining method |
| CN109676167A (en) * | 2019-02-28 | 2019-04-26 | 常州机电职业技术学院 | A kind of special holder and its application method of horizontal lathe processing deep and long hole |
| CN111093870A (en) * | 2017-09-07 | 2020-05-01 | Osg株式会社 | Deep hole machining method |
-
2021
- 2021-10-11 CN CN202111183701.XA patent/CN113878135B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1593788A1 (en) * | 1987-11-16 | 1990-09-23 | Ленинградский механический институт им.Маршала Советского Союза Устинова Д.Ф. | Method and apparatus for working deep holes |
| CN103028752A (en) * | 2012-11-28 | 2013-04-10 | 湖北三环锻压设备有限公司 | Processing method for phi 52H7*850 deep hinge pin keyhole at matched position of parts of different materials |
| CN104625152A (en) * | 2014-12-02 | 2015-05-20 | 李连江 | Method for machining deep hole of long-cylinder part |
| CN111093870A (en) * | 2017-09-07 | 2020-05-01 | Osg株式会社 | Deep hole machining method |
| CN107598204A (en) * | 2017-10-10 | 2018-01-19 | 上海第机床厂有限公司 | The deep hole processing method of CRDM drive rod |
| CN108115176A (en) * | 2017-12-18 | 2018-06-05 | 航天科工哈尔滨风华有限公司 | A kind of high-precision step shaft titanium alloy material Fine and Deep Hole high-efficiency machining method |
| CN109676167A (en) * | 2019-02-28 | 2019-04-26 | 常州机电职业技术学院 | A kind of special holder and its application method of horizontal lathe processing deep and long hole |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113878135A (en) | 2022-01-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204711261U (en) | Bull puncher | |
| CN113878135B (en) | Boring processing method for ultra-long hole of special-shaped part | |
| CN203438012U (en) | Novel horizontal machining center with composite gun-drill function | |
| CN201102091Y (en) | Gang tool for step hole process | |
| CN201195212Y (en) | Single-side chamfering machine | |
| CN208744149U (en) | One kind having multi-functional horizontal Machining centers device | |
| CN103817366A (en) | Combined chambering cutter | |
| CN203679358U (en) | Deep hole machining cutter system capable of preventing bending deformation of cutter bars | |
| CN204171383U (en) | A kind of deep hole quick change knife bar | |
| CN204603417U (en) | A kind of dual output milling head | |
| CN205129023U (en) | Drilling chamfer synthetics | |
| CN209811744U (en) | Supporting mechanism | |
| CN210498493U (en) | Step hole compound cutter | |
| CN201895101U (en) | Horizontal double-surface and double-station drill and ream combined machine tool | |
| CN203791653U (en) | Boring bar mechanism for inner hole chamfering of boring box | |
| CN203804269U (en) | Deep processing device of boring machine or milling machine | |
| CN201089027Y (en) | Drilling-milling combined tools | |
| CN203426475U (en) | Boring and rolling integrated tool for machining deep hole | |
| CN202219330U (en) | Transitional jacket for boring cutters | |
| CN202291442U (en) | Rose reamer | |
| CN205289943U (en) | Reamer with interior cold -working is used | |
| CN205074802U (en) | Radial dowelling jig of tubulose work piece is cut and is used convertible frock | |
| CN205414476U (en) | A processingequipment that is used for square forging cross hole | |
| CN204818196U (en) | From BTA tooling system of rectifying | |
| CN204770735U (en) | Advance boring cutter to one side |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |