This standard specifies the type and size, technical requirements and basic requirements for marking and packaging of 60° tapered pipe thread rolling plates. This standard is applicable to taps for processing 60° tapered pipe threads (NPT) with thread size codes of 1/16~3/4. JB/T 8364.4-1996 60° tapered pipe thread rolling plates JB/T8364.4-1996 Standard download decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
JB/T 8364. 4--96
60° Taper Pipe Thread Rolling Plate
1996-04-22 Issued
Ministry of Machinery Industry of the People's Republic of China
1996-07-01 Implementation
JB/T 8364.4-96
Appendix A and Appendix C of this standard are both standard appendices. Appendix B of this standard is a suggestive appendix.
This standard is proposed and managed by the National Technical Committee for Tool Standardization.
The responsible drafting units of this standard are: Shanghai Cutting Tool Factory, Shanghai Standard Parts Tool Factory, Chengdu Tool Research Institute. The main drafters of this standard are: Wang Yongfeng, Ye Fudi, Jiang Tigui, Yu Jin. This standard was first issued on April 22, 1996. This standard shall be implemented from July 1, 1996. Scope
Machinery Industry Standard of the People's Republic of China
60° Taper Pipe Thread Rolling Plate
JB/T 8364. 4—96
This standard specifies the type and size, technical requirements and basic requirements for marking and packaging of 60° tapered pipe thread rolling plates. This standard is applicable to the rolling plates for processing 60° tapered pipe threads (NPT) with thread size codes of 1/16 to 3/4. Type and size
2.1 The type and size of the rolling plates shall be as specified in Figure 1 and Table 1. 25
Installation surface
Bearing surface
Movable thread rolling plate
Approved by the Ministry of Machinery Industry on April 22, 1996
Fixed thread rolling plate
Figure 1 Type and size of thread rolling plate
Implementation on July 1, 1996
JB/T 8364.4-96
Dimensions of thread rolling plate
The thread profile and size of the thread rolling plate shall be in accordance with the provisions of Figure 2 and Table 2. 2.2
31°4724\
2°24'5\
1°48°29\
2°330\
1°55'5\
1°40'37\
1°19'1″Www.bzxZ.net
28°12'36
0.991°33
48.511.27
Note: The top and bottom of the thread rolling plate are allowed to be rounded, but the position of the rounded position shall not exceed the provisions of the thread tooth type [see Appendix A (Standard Appendix) for details] Figure 2 Thread profile of thread rolling plate
Table 2 Thread profile dimensions of thread rolling plate
Number of teeth per 25.4mm
Pitch P
Basic dimensions
Limit deviation
Note: For the use and installation of thread rolling plates, see Appendix B (suggestive appendix). 2.3 Marking example
60° tapered pipe thread, thread rolling plate code NPT1/4: 2
Pitch deviation
(25.4mm above)
Thread profile half angle
JB/T 8364. 4- 96
60° tapered pipe thread rolling plate NPT1/4JB/T8364.4-9660° tapered pipe thread, code NPT1/4, left-hand thread rolling plate: 60° tapered pipe thread rolling plate NPT1/4-LJB/T8364.4-963 Technical requirements
3.1 The surface of the rolling plate shall not have defects such as cracks, chipping, rust and grinding burns that affect the performance. 3.2 The upper limit of the surface roughness of the rolling plate shall be as follows: Thread surface
R,6.3 μm;
device and supporting surface R.0.8um. ​​
3.3 In a pair of thread rolling plates, the width difference between the fixed thread rolling plate and the movable thread rolling plate should not exceed 0.10mm. 3.4 The intersection of the plane perpendicular to the thread rolling plate supporting surface and the tooth top plane, the parallelism tolerance of the supporting surface shall be as follows: a) Width direction:
Code NPT1/16~1/20.07mm;
Code NPT3/4
b) Length direction:
0.08 mm.
Code NPT1/16～1/20.09 mm;
Code NPT3/4
0.11 mm.
3.5 The verticality tolerance of the thread rolling plate support surface to the installation surface is 0.33mm. 3.6 The deviation of the thread rolling plate thread lead angle is ±3', and the difference between a pair of thread rolling plates is 3°. The thread rolling plate is made of Cr12MoV or 9SiCr alloy tool steel. When made of Cr12MoV, the unevenness of its carbide is not greater than 33.7
The hardness of the working part of the thread rolling plate is not less than 58HRC, and there should be no decarburization and reduced hardness on the working surface. 4 Marking and packaging
4.1 Marking
4.1.1 The thread rolling plate should be marked with:
a) manufacturer's trademark;
b) thread code;
c) material code;
d) installation direction.
4.1.2 The packaging box should be marked with:
a) manufacturer's name, trademark and address;
b) items specified in the example of thread rolling plate marking; c) material brand or code;
d) number of pieces;
e) year and month of manufacture.
4.2 Packaging
The thread rolling plate should be rust-proofed before packaging. The packaging must be firm and prevent damage during transportation. 3
JB/T 8364. 4-96
Appendix A
Tolerances of crest height and root height of tapered pipe threads (Standard Appendix)
A1 The tolerances of crest height and root height of tapered pipe threads are shown in Figure A1 and Table A1. Tolerance of crest (or root) height
Tolerance of root (or crest) height
Note: The text in brackets refers to internal threads. Figure A1
Tolerance table of crest height and root height of tapered pipe threads Al
Number of threads per 25.4mm n
Tolerance of crest height and root height of threads
Tolerance of crest height and root height of threads
A2In actual production, the crest and root of threads are generally circular. A2.1The arc of the crest of the thread is allowed to exceed the crest tolerance zone, but the vertex of the arc cannot leave the crest tolerance zone, see Figure A2. A2.2The arc of the thread root cannot exceed the root tolerance zone, see Figure A2. External thread
Figure A2 Rounding of internal thread crest and root
JB/T8364.4-96
Appendix B
Use and installation of thread rolling plate
(Appendix of suggestion)
B160° tapered pipe thread thread rolling plate use and installation see Figure B1. Workpiece
Mark "installation upward" here
31°47'24
28°12'36\
1°47*24*
147'24\
Mark "installation upward" here
31°4724\
2812'36\
1°47'24\
JB/T 8364. 4 - 96
Appendix C
Basic dimensions and element deviations of tapered pipe threads (Appendix to the standard)
Basic dimensions of tapered pipe threads are shown in Table C1. Table C1 Basic dimensions of tapered pipe threads
Number of threads per 25.4 mm
Major diameter (reference diameter)
The element deviations of tapered pipe threads are shown in Table C2 Basic dimensions||t t||The limit deviation of the tooth profile half angle, cone half angle and pitch of tapered pipe thread
Number of teeth within 25.4mm
Deviation of tooth profile half angle
Taper tolerance
+2649\
-8°56
+17'53*
±8°56”
Reference distance
Pitch deviation (25.4mm above)
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