CN111168164A - Machining method and machining tool for thread ring gauge - Google Patents
Machining method and machining tool for thread ring gauge Download PDFInfo
- Publication number
- CN111168164A CN111168164A CN201811347244.1A CN201811347244A CN111168164A CN 111168164 A CN111168164 A CN 111168164A CN 201811347244 A CN201811347244 A CN 201811347244A CN 111168164 A CN111168164 A CN 111168164A
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- thread
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- 238000000034 method Methods 0.000 title claims abstract description 43
- 238000003754 machining Methods 0.000 title claims abstract description 20
- 238000003672 processing method Methods 0.000 claims abstract description 11
- 238000007517 polishing process Methods 0.000 claims description 6
- 238000010327 methods by industry Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 239000011295 pitch Substances 0.000 description 17
- 238000005498 polishing Methods 0.000 description 8
- 239000000463 material Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000012797 qualification Methods 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 229910001060 Gray iron Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23G—THREAD CUTTING; WORKING OF SCREWS, BOLT HEADS, OR NUTS, IN CONJUNCTION THEREWITH
- B23G1/00—Thread cutting; Automatic machines specially designed therefor
- B23G1/44—Equipment or accessories specially designed for machines or devices for thread cutting
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention discloses a method for processing a thread ring gauge, which comprises a method for processing a first type of thread ring gauge with the diameter larger than 50mm and the thread pitch not smaller than 2mm and a method for processing a second type of thread ring gauge with the diameter smaller than 50 or the thread pitch smaller than 2 mm; the first type of thread ring gauge is processed by the following method: grinding and processing by adopting an internal thread grinding machine, and reserving grinding allowance not more than 0.05mm according to the tolerance size of the intermediate diameter and the aperture of the first type of thread ring gauge; the processing method of the second type of thread ring gauge comprises the following steps: and (5) processing by adopting a grinding process. The invention also discloses a machining tool of the thread ring gauge. The single-parameter thread ring gauge is suitable for production and machining of single-parameter thread ring gauges, machining precision is convenient to control, product quality is guaranteed, and production efficiency is improved.
Description
Technical Field
The invention relates to a measuring tool, in particular to a machining method and a machining tool for a threaded ring gauge.
Background
The qualified rate of the thread ring gauge is up to more than 95% when the thread ring gauge is machined by using a calibrated thread plug gauge under the normal condition of a process system, the qualified rate of the thread ring gauge measured by using a single parameter of an instrument is not up to 5%, a horn mouth, half angles and thread pitches are unqualified when the ring gauge is ground, the middle diameter size is not well controlled, the time is large and the time is small, the change is abnormal, and the size of each single parameter cannot be controlled.
Disclosure of Invention
The invention aims to provide a processing method and a processing tool of a thread ring gauge, which are suitable for the production and processing of a single-parameter thread ring gauge, are convenient to control the processing precision, ensure the product quality and improve the production efficiency.
In order to achieve the purpose, the invention is realized by adopting the following technical scheme:
the invention discloses a processing method of a thread ring gauge, which comprises a processing method of a first type of thread ring gauge with the diameter larger than 50mm and the thread pitch not smaller than 2mm and a processing method of a second type of thread ring gauge with the diameter smaller than 50 or the thread pitch smaller than 2 mm;
the processing method of the first type of thread ring gauge comprises the following steps: grinding and processing by adopting an internal thread grinding machine, and reserving grinding allowance not more than 0.05mm according to the tolerance size of the intermediate diameter and the aperture of the first type of thread ring gauge;
the processing method of the second type of thread ring gauge comprises the following steps: and (5) processing by adopting a grinding process.
Furthermore, in the grinding process engineering of the internal thread grinding machine, a pitch diameter measuring instrument and a calibration gauge are used for controlling the size on line.
Preferably, the thread ring gauge with the diameter larger than 16mm in the second type of thread ring gauge is turned by a numerical control lathe, and then a grinder is used for grinding the threads.
Preferably, the thread ring gauge with the diameter not greater than 16mm in the second type of thread ring gauge adopts a screw tap to process threads, and then a grinder is used for grinding the threads.
Preferably, the grinding length of the grinder is not more than the length of two machined threaded ring gauges, the grinding comprises a rough grinding process, a fine grinding process and a polishing process which are sequentially performed, and different grinding sands are respectively adopted in the rough grinding process, the fine grinding process and the polishing process.
The invention also discloses a processing tool of the thread ring gauge, which comprises a grinder A, wherein the grinder A comprises a grinding head and a holding part, the rear end of the grinding head is connected with the front end of the holding part, the grinding head is provided with external threads A, the length of the external threads A is not more than the length of two thread ring gauges to be processed, the rear end of the holding part is provided with a blind hole, the axis of the blind hole is superposed with the axis of the grinding head and the axis of the holding part, the blind hole comprises a cylindrical section and a truncated cone section, the small end of the truncated cone section is connected with the cylindrical section, and the large end of the truncated cone section is positioned on the rear end wall of the holding part.
Furthermore, the grinding head is connected with the holding part through a connecting section, the axis of the connecting section is overlapped with the axis of the grinding head, the diameter of the connecting section is smaller than the diameter of the grinding head and the diameter of the holding part, a guide section is arranged at the front end of the grinding head, the axis of the guide section is overlapped with the axis of the grinding head, and the diameter of the guide section is smaller than the diameter of the grinding head and the diameter of the holding part.
Further, the machining tool further comprises a grinder B, the grinder B is provided with an axial through hole, the grinder B comprises two thread sections and two clamping sections, the two clamping sections are connected to two ends of the thread sections respectively, the thread sections are provided with external threads B, the length of the thread sections is not greater than the length of two thread ring gauges to be machined, the outer diameter of the clamping sections is smaller than the outer diameter of the portion provided with the external threads B, a seam allowance is arranged at the joint of the clamping sections and the thread sections, and the axial through hole is a conical hole.
Preferably, the thread half angle of the external thread A and the thread half angle of the external thread B are 30 degrees, and the tolerance is-10 minutes.
Furthermore, the processing tool also comprises a screw tap, wherein the back taper angle of the screw tap is 0.05-0.08/100mm, and two ends of the screw tap are provided with central holes.
The invention has the following beneficial effects:
1. the thread ring gauges with different diameters are classified, and different machining methods are adopted, so that the tooth surface roughness and angle change of the thread ring gauges can be better controlled.
2. The invention is suitable for the production and processing of the single-parameter thread ring gauge, is convenient to control the processing precision, ensures the product quality and improves the production efficiency.
Drawings
FIG. 1 is a schematic view of a grinder A;
FIG. 2 is a schematic structural view of an external thread A and an external thread B;
FIG. 3 is a schematic view of the grinder B;
FIG. 4 is a left side view of FIG. 3;
FIG. 5 is a schematic view of the tap construction;
fig. 6 is a cross-sectional view of the thread of the tap.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings.
The invention discloses a method for processing a thread ring gauge, which comprises a method for processing a first type of thread ring gauge with the diameter larger than 50mm and the thread pitch not smaller than 2mm and a method for processing a second type of thread ring gauge with the diameter smaller than 50 or the thread pitch smaller than 2 mm.
The first type of thread ring gauge is processed by the following method: and (3) grinding by using an internal thread grinding machine, reserving grinding allowance not more than 0.05mm according to the tolerance size of the pitch diameter and the aperture of the first type of thread ring gauge, and controlling the size on line by using a pitch diameter measuring instrument and a calibration gauge in the grinding process engineering by using the internal thread grinding machine.
The processing method of the second type of thread ring gauge comprises the following steps: the thread ring gauge with the diameter larger than 16mm in the second type of thread ring gauge is turned by a numerical control lathe to form threads, and then the threads are ground by a grinder; and the thread ring gauge with the diameter not more than 16mm in the second type of thread ring gauge adopts a screw tap to process threads, and then a grinder is used for grinding the threads. The grinding length of the grinder is not more than the length of the two machined threaded ring gauges, the grinding comprises a rough grinding process, a fine grinding process and a polishing process which are sequentially carried out, and different grinding sands are respectively adopted in the rough grinding process, the fine grinding process and the polishing process.
1. And the ring gauge with the diameter of more than 50mm and the thread pitch of more than or equal to 2mm adopts an internal thread grinding machine grinding mode. According to the tolerance of the pitch diameter and the bore diameter of the thread ring gauge, a proper grinding allowance is reserved, and the grinding allowance is generally not more than 0.05 mm. And carrying out size control on the wire by adopting a pitch diameter measuring instrument and a calibration gauge.
2. The ring gauge with the diameter less than 50mm or the screw pitch less than 2mm adopts a grinding process.
(1) Wherein the diameter is more than 16, the thread is turned by a numerical control lathe, and the process control is key: a. and controlling the turning process, wherein the turning process is implemented by making a first piece on an instrument, and each 30 pieces are processed to carry out inspection, so that the turning angle and the size of the silk bottom are ensured. b. The lapping grinder of each specification ring gauge replaces the original turning process with grinding, and the tooth form half angle and thread pitch precision of the grinder are guaranteed, so that the grinding precision of the ring gauge is guaranteed. c. The structure of the grinder is adjusted, the length only allows grinding to be not more than the length of two ring gauges, and the number of grinding pieces is controlled; the angle of the grinder is adjusted according to the angle of each batch of ring gauges, so that the grinding qualification of the half angle is guaranteed to the maximum extent. d. Rough grinding, fine grinding and polishing are performed in sequence, grinding sand with different particle sizes is adopted according to different screw pitches, and the roughness and the angle change of the tooth surface are well controlled.
(2) Wherein the diameter is less than 16, the grinding process after screw tap processing is adopted, and the control key points are as follows: a. adjusting the size of the medium-diameter screw tap, controlling the grinding allowance, shortening the length of the original screw tap and increasing the front angle of the screw tap. The major diameter size of the bottom-end tap is reduced, the service life of the tap is prolonged, the bottom-end tap of the end-stop ring gauge is redesigned, the tooth surface length is ensured, and the single-parameter detection qualified rate is improved. b. The structure of the grinder is adjusted, the length only allows grinding to be not more than the length of two ring gauges, and the number of grinding pieces is controlled; the angle of the grinder is adjusted according to the angle of each batch of ring gauges, so that the grinding qualification of the half angle is guaranteed to the maximum extent. c. Rough grinding, fine grinding and polishing are performed in sequence, grinding sand with different particle sizes is adopted according to different screw pitches, and the roughness and the angle change of the tooth surface are well controlled. d. The accumulated pitch out-of-tolerance problem of the ring gauge at the section is well solved by machining with a hard alloy screw tap after firing.
The invention also discloses a machining tool suitable for the machining method, which comprises a grinder A, a grinder B and a screw tap.
As shown in fig. 1, the grinder a comprises a grinding head 3 and a holding part 1, the rear end of the grinding head 3 is connected with the front end of the holding part 1, the grinding head 3 is provided with an external thread a, the length of the external thread a is not more than the length of two thread ring gauges to be processed, the rear end of the holding part 1 is provided with a blind hole 5, the axis of the blind hole 5 is coincident with the axis of the grinding head 3 and the axis of the holding part 1, the blind hole 5 comprises a cylindrical section and a truncated cone section, the small end of the truncated cone section is connected with the cylindrical section, and the large end of the truncated cone section is located on the rear end wall of the holding part 1; the polishing head 3 and the holding part 1 are connected through a connecting section 2, the axis of the connecting section 2 is overlapped with the axis of the polishing head 3, the diameter of the connecting section 2 is smaller than the diameter of the polishing head 3 and the diameter of the holding part 1, a guide section 4 is arranged at the front end of the polishing head 3, the axis of the guide section 4 is overlapped with the axis of the polishing head 3, and the diameter of the guide section 4 is smaller than the diameter of the polishing head 3 and the diameter of the holding part 1. The grinder A is suitable for thread ring gauges of M4-M12, the length of the grinder A is 40-80mm, the roughness of the grinding head 3 is 0.8, and the conical angle of the truncated conical section is 60 degrees.
As shown in fig. 3 and 4, the grinder B is provided with an axial through hole 10, the grinder B comprises a thread section 7 and two clamping sections 9, the two clamping sections 9 are respectively connected to two ends of the thread section 7, the thread section 7 is provided with an external thread B8, the length of the thread section 7 is not more than the length of two thread ring gauges to be processed, the outer diameter of the clamping section 9 is smaller than the outer diameter of the thread section 7, a seam allowance is arranged at the joint of the clamping section 9 and the thread section 7, and the axial through hole 10 is a tapered hole. The grinder B is suitable for a threaded ring gauge larger than M12, the length of the grinder B is 40-100mm, the roughness of the thread section 7 is 0.8, the roughness of the inner wall of the axial through hole 10 is 3.2, the outer diameter range of the thread section 7 is 4-180mm, wherein the inclination angle of the inner wall of the axial through hole 10 of M12-M25 is 57 minutes, and the taper is 1: 30; M16-M180, the inclination angle of the inner wall of the axial through hole 10 is 1 degree and 26 minutes, and the taper is 1: 20.
As shown in fig. 2, the half-angle of the teeth 6 of the external thread A and the external thread B8 is 30 degrees, the tolerance is minus 10 minutes, the thread pitch range is 1.0-6.0, the material of the grinder A with the size of M8 and below is steel 35, the material of the grinder A or the grinder B with the size of M8 is gray cast iron HT20-40, and the hardness is HB 140-180.
As shown in fig. 5 and 6, the tap comprises a guide part 14, a cutting part 12, chip flutes 13 and a holding part 11, the back taper angle of the tap is 0.05-0.08/100mm, and both ends of the tap are provided with central holes.
The present invention is capable of other embodiments, and various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention.
Claims (10)
1. The processing method of the thread ring gauge is characterized in that: the method comprises a first type of thread ring gauge with the diameter larger than 50mm and the thread pitch not smaller than 2mm and a second type of thread ring gauge with the diameter smaller than 50 or the thread pitch smaller than 2 mm;
the processing method of the first type of thread ring gauge comprises the following steps: grinding and processing by adopting an internal thread grinding machine, and reserving grinding allowance not more than 0.05mm according to the tolerance size of the intermediate diameter and the aperture of the first type of thread ring gauge;
the processing method of the second type of thread ring gauge comprises the following steps: and (5) processing by adopting a grinding process.
2. A method of machining a threaded ring gauge according to claim 1, characterized in that: in the grinding process engineering of the internal thread grinding machine, the size is controlled on line by adopting a pitch diameter measuring instrument and a calibration gauge.
3. A method of machining a threaded ring gauge according to claim 1, characterized in that: and the thread ring gauge with the diameter larger than 16mm in the second type of thread ring gauge is used for turning threads by a numerical control lathe, and then the threads are ground by a grinder.
4. A method of machining a threaded ring gauge according to claim 1, characterized in that: and the thread ring gauge with the diameter not more than 16mm in the second type of thread ring gauge adopts a screw tap to process threads, and then a grinder is used for grinding the threads.
5. A method of machining a threaded ring gauge according to claim 3 or 4, characterized in that: the grinding length of the grinder is not more than the length of the two machined threaded ring gauges, the grinding comprises a rough grinding process, a fine grinding process and a polishing process which are sequentially carried out, and different grinding sands are respectively adopted in the rough grinding process, the fine grinding process and the polishing process.
6. A machining tool adapted for use in the machining method according to claim 4, wherein: including grinder A, grinder A includes grinding head and control portion, the front end of control portion is connected to the rear end of grinding head, and the grinding head is equipped with external screw thread A, external screw thread A's length is not more than the length of two screw ring gauges of treating processing, the rear end of control portion is equipped with the blind hole, the axis of blind hole and the axis of grinding head, the axis coincidence of control portion, the blind hole include the cylinder section and with the truncated cone section, the cylinder section is connected to the tip of truncated cone section, and the main aspects of truncated cone section is located the rear end wall of control portion.
7. The machine tool of claim 6, wherein: the grinding head is connected with the holding part through a connecting section, the axis of the connecting section is overlapped with the axis of the grinding head, the diameter of the connecting section is smaller than the diameter of the grinding head and the diameter of the holding part, a guide section is arranged at the front end of the grinding head, the axis of the guide section is overlapped with the axis of the grinding head, and the diameter of the guide section is smaller than the diameter of the grinding head and the diameter of the holding part.
8. The machine tool of claim 6 or 7, wherein: still include mill B, mill B is equipped with axial through hole, and mill B includes screw thread section and centre gripping section, the centre gripping section has two, connects respectively at the both ends of screw thread section, the screw thread section is equipped with external screw thread B, and the length of screw thread section is not more than the length of two screw thread ring gauges of treating processing, and the external diameter of centre gripping section is less than the external diameter of the part that is equipped with external screw thread B, and the junction of centre gripping section and screw thread section is equipped with the tang, axial through hole is the bell mouth.
9. The machine tool of claim 8, wherein: the thread half angle of the external thread A and the thread half angle of the external thread B are 30 degrees, and the tolerance is-10 minutes.
10. The machine tool of claim 6, wherein: the screw tap is characterized by further comprising a screw tap, wherein the back taper angle of the screw tap is 0.05-0.08/100mm, and two ends of the screw tap are provided with central holes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811347244.1A CN111168164A (en) | 2018-11-13 | 2018-11-13 | Machining method and machining tool for thread ring gauge |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811347244.1A CN111168164A (en) | 2018-11-13 | 2018-11-13 | Machining method and machining tool for thread ring gauge |
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| Publication Number | Publication Date |
|---|---|
| CN111168164A true CN111168164A (en) | 2020-05-19 |
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| CN201811347244.1A Pending CN111168164A (en) | 2018-11-13 | 2018-11-13 | Machining method and machining tool for thread ring gauge |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115156856A (en) * | 2022-07-28 | 2022-10-11 | 江苏新广联科技股份有限公司 | Thread gauge manufacturing process |
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-
2018
- 2018-11-13 CN CN201811347244.1A patent/CN111168164A/en active Pending
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115156856A (en) * | 2022-07-28 | 2022-10-11 | 江苏新广联科技股份有限公司 | Thread gauge manufacturing process |
| CN115156856B (en) * | 2022-07-28 | 2023-09-12 | 江苏新广联科技股份有限公司 | Thread gauge manufacturing process |
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