JB/T 54882-1999 Quality classification of machine taps JB/T54882-1999 standard download decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
JB/T54882-1999
Product Quality Grading
Machine Taps
(Internal Use)
Published on 1999-12-30
National Bureau of Machinery Industry
Implemented on 2000-06-01
JB/T54882-1999
This standard is a revision of JB/T54882-93 "Product Quality Grading of Machine Taps". As the machine tap product standard has been revised, some technical contents and clauses have changed. This standard has been revised according to the corresponding machine tap product standard. This standard adjusts individual assessment items from Class B Unqualified Group I to Class B Unqualified Group II, makes corresponding adjustments to the RQL value of Class B Unqualified Group IⅡI, and adds provisions for allowing special inspection levels for Class B Unqualified Group IⅡI. This standard includes the quality classification of nut taps.
This standard replaces JB/T54882-93 from the date of implementation. This standard is proposed and managed by the National Technical Committee for Tool Standardization. The responsible drafting unit of this standard: Chengdu Tool Research Institute. 1 Scope
Machinery Industry Standards of the People's Republic of China
Quality Classification of Machine Taps
(Internal Use)
JB/T54882-1999
Replaces JB/T54882-93
This standard specifies the AQL value of machine taps and nut taps when quality grade assessment is carried out according to JB/T54854, the RQL value of periodic stability assessment, unqualified classification and life test. This standard applies to the quality grade assessment and periodic stability assessment of machine taps and nut taps produced in batches according to GB/T967~969, GB/T3464.1~3464.3, and JB/T8786. Cited standardswww.bzxz.net
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard was published, the versions shown were valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T 967—1994
GB/T 9681994
GB/T 9691994
GB/T 3464.1—1994
GB/T3464.2—1994
GB/T3464.3—1994
JB/T8786—1998
JB/T99871999
JB/T54854—1999
3Specified value of AQL
Screw Female taps
Tap thread tolerances
Technical conditions for taps
Machine and hand taps
Long-shank machine taps
Short-shank machine and hand taps
Long-shank nut taps
Diameter of twist drill for drilling before tapping
General rules for tool product quality classification
The specified values ​​of AQL are given in Table 1.
Product grades
Qualified products
Superior products
4The specified values ​​of RQL
The specified values ​​of RQL are given in Table 2.
Approved by the State Bureau of Machinery Industry on December 30, 1999
Unqualified
Class C unqualified
Implemented on June 1, 2000
Product grade
Qualified product
Superior product
Unqualified classification and grouping
JB/T54882-1999
Unqualified
Class C unqualified
Unqualified classification and grouping are given in Table 3. Special inspection level is allowed for Class B unqualified II group in Table 3 during batch-by-batch warehousing inspection.
Class B unqualified
Class B unqualified
Class B unqualified
Class C unqualified
Unqualified items
1) There are cracks, chipping, burns, blunt cutting edges, sand holes in the weld of welding tools and other unqualified items that affect the performance;
2) The surface roughness of the front does not meet the standard requirements; 3) The surface roughness of the back does not meet the standard requirements; 4) The surface roughness of the thread does not meet the standard requirements; 5) The major diameter and the middle diameter are out of tolerance;
6) The thread tooth profile is not ground:
7) The material does not meet the standard requirements:
8) Standard Marking and packaging do not meet the standards
1) The oblique circular runout of the cutting part and the radial circular runout of the calibration part are out of tolerance: 2) The pitch, tooth profile half angle, and minor diameter are out of tolerance
1) The hardness of the threaded part does not meet the standards: 2) The cutting performance does not meet the requirements of the standards 1) The hardness of the square head does not meet the standards
2) The tap groove is not ground or polished:
3) The square head of the tap:
a) The shape error of the square head of a high-performance machine tap and its position error to the shank axis are out of tolerance; b) The square head size of ordinary machine taps and nut taps and the symmetry of the square head to the shank axis are out of tolerance;
4) The straightness of the shank Diameter out of tolerance;
5) No back taper in the middle diameter;
6) Shank radial runout out of tolerance (not specified for ordinary long-shank machine taps and long-shank nut taps) 7) The total length of the tap and the length of the threaded part out of tolerance: 8) The surface roughness of the shank does not meet the standard requirements; 9) There are the following minor visual failures: There are slight scratches and slight rust on the cutting edge, a small amount of black spots and rust on other surfaces, and a yellow oxide film caused by grinding. Judgment basis
According to GBT969
According to GBT969
According to GBT969
According to GBT968
According to GBT969
|According to GBT9
According to GBT99
According to GBT969
According to GBT968
According to GBT969
According to GBT969
According to GBT99
According to GBT99
According to GBT99
According to GBT99
According to GBT969
Life test
Test conditions
JB/T54882-1999
Machine tool: vertical drilling machine that meets the precision requirements. 6.1.2 Cutting tools: number of samples - 5~10 pieces.
6.1.3 Test damage: The material is 40Cr steel, quenched and tempered, with a hardness of 200~220HB. Cutting specifications: as specified in Table 4.
6.1.5 Cutting fluid: Use 5% emulsified oil-water solution for sufficient cooling, and its flow rate should be no less than 5L/min. 6.1.6 Screw hole form: Through hole, when d≤6mm, the hole depth is 1.5d; when d6mm, the hole depth is 2d. The diameter of the hole before tapping should be in accordance with the provisions of JB/l9987.
6.1.7 Tool clamping: Clamped with a tapping chuck, the maximum radial runout of the cutting part is 6≤0.10mm. 6.2 Test result evaluation
6.2.1 Life criterion:
a) The thread plug gauge cannot pass through the end;
b) The end of the thread plug gauge passes through 5 holes continuously; c) The maximum wear value VBmax of the main back of the tap cutting tooth reaches the requirements of Table 4; d) The surface roughness Ra value of the test piece thread is 6.3μm; e) Chipping occurs: CHF0.60P (P1mm), CHF0.5P (P>1~2mm), CH0.40P (P>2mm), or other phenomena that cannot cut normally.
6.2.2 Life indicators are given in Table 4.
Nominal diameter d
>12-24
>24-50
Cutting speed V
Maximum wear value VBmax
Average life T
Coefficient of variation CV
Average life T
Coefficient of variation Cv
People's Republic of China
Mechanical industry standards
Quality classification of machine taps
(for internal use)
JB/T54882-1999
Mechanical Science Published by the Academy of Mechanical Science
Printed by the Academy of Mechanical Science
(No. 2, Shouti South Road, Beijing
Postal Code: 100044)
Format: 880×12301/16 Printing Sheet: 1/2 Word Count: 8000First Edition: May 2000
First Printing: May 2000
Price: RMB 10.00
Print Quantity: 1-500
Number: 99-1758
Mechanical Industry Standard Service Network: http:/www.jb.ac.cn6668
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