This standard specifies the technical requirements, inspection methods and acceptance rules for induction hardening and tempering of metal cutting machine tool parts. This standard applies to parts such as structural steel, tool steel, bearing steel, etc. that have been induction hardened and tempered. JB/T 8491.3-1996 Technical conditions for heat treatment of machine tool parts Induction hardening and tempering JB/T8491.3-1996 Standard download decompression password: www.bzxz.net

The Machinery Industry Standard of the People's Republic of China
JBT8491.3-1996
Technical Conditions for Heat Treatment of Machine Tool Parts
Induction Quenching and Tempering
Published on November 7, 1996
Ministry of Machinery Industry of the People's Republic of China
Implementation on January 1, 1997
JE/T8491.3-1996
This standard is based on the summary of many years of production experience in heat treatment of machine tool parts in my country and the transmission of foreign technical data. This standard is based on the application of B/T54216-94 "General Technical Specification for Induction Quenching and Tempering of Machine Tool Parts". This standard is proposed by the National Technical Committee for Standardization of Metal Cutting Machines. This standard is formulated by the Beijing Machine Tool Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Beijing Machine Tool Research Institute of the Ministry of Machinery Industry. This standard was first issued in 1994.
Machinery Industry Standard of the People's Republic of China
Technical Conditions for Heat Treatment of Machine Tool Parts
Induction Hardening and Tempering
JR/T 9491.3-1996
T54316——94
This standard specifies the technical requirements, inspection methods and acceptance rules for induction hardening and tempering of machine tool parts (hereinafter referred to as parts).
This standard is applicable to structural, tool steel, bearing steel and other parts that have been subjected to induction hardening and tempering. Reference Standards
The provisions contained in the following standards are referred to in this document and become the main text of this standard. The versions shown are valid at the time of publication of this standard. All standards are subject to revision: all parties using this standard should explore the possibility of using the latest versions of the following standards. GB 230—91
GB 56:7-83
Metallurgical induction test method
Determination of effective corrosion depth of induction fire or flame rate fire GB/T13298—91
Metal microscopic inspection methodwww.bzxz.net
JB125591
ZB J36 00387
ZB J36 009
3 Appearance quality
Technical conditions for heat treatment of high carbon chromium steel parts Metallographic inspection of heat treatment of tools
Metallurgical inspection of induction fire of parts
3.1 The surface of the parts shall be clean and free from cracks, scratches, rust and bumps. 3.2 Inspection of appearance shall be carried out with naked eyes or a low-power magnifying glass. If necessary, the cracks may be inspected by sandblasting or flaw detection. Surface hardness
4.1 The surface hardness of the workpiece shall comply with the requirements of the drawing and process documents. The surface hardness tolerance is -1IRC4.1 Test hardness by the method specified in G230. When it is not suitable to adopt the specified method, other hardness test methods can also be used. 5 Effective hardening depth
5.1 The effective hardening layer depth of the part shall comply with the requirements of the sample and process documents. The effective hardening layer depth tolerance is shown in Table 1. Approved by the Ministry of Machinery Industry on November 7, 1996, implemented on January 1, 1997, nominal depth JB/T 8491.3—1996, effective hardening depth consistency should not exceed the requirements of Table 2, but for parts with complex shapes or large sizes, there is a large fluctuation range, Table 2, effective reverse layer depth ≥1.5~2.5, method: the same batch of materials refers to parts from the same batch of materials processed in the same furnace. 5.3 Check the effective plasticized layer depth by the method specified in GB5617 on the simulated test specimen of the parts. 6 Strict hard zone, teaching belt or non-rate zone position and size 6.1 The position of the rate hard zone shall comply with the provisions of the drawing and technical documents, and the size tolerance of the pump specification is generally: medium version upper mm; starting height ±4mm
6.2 The width of the belt or end rate zone
621 When there are gods and holes on the surface of the hard layer, the width of the soft belt or rice zone near the hole and the end of the part (see Figure 1) is: medium frequency minimum F or equal to 12 mm: ultra-high frequency minimum ten or equal ten Bmm figure,
JB/T 8491.3—1996
6.2.2 When the outer diameter of the two steps is small and hard, the width of the annular soft zone or soft zone A (see Figure 2) at the step should comply with the provisions of Figure 2, Figure 2
Additional equipment
Super high-efficiency
Donkey-like shaft, the return diameter difference is-
The width of the soft zone or the soft zone
%2.3 There is a hole in the lower part of the hard layer, and the minimum thickness 3 is less than 5 times the depth of the effective hardened layer, the width 4 of the soft zone or the soft zone in the economic hardening zone (see Figure 3) should not exceed the depth of the hole,
62.4 When the production zone cannot be continuously crushed, the width 4, 8 of the soft zone at the joint (see Figure 4) should comply with the provisions of Table 2.
Additional frequency and high pressure
Soft belt modification
JR/T 8491.3-1996
6.2.5 When the inner end face of the flange is hardened, the width A of the annular soft belt or the soft belt area around the adjacent axis (Figure 5) is: less than or equal to 12mm: super-high frequency, less than or equal to 8mm (Figure 5)
6.2. On the two intersecting surfaces, the width of the soft belt or the end area at the intersection (Figure 6) is: less than or equal to 15mra; less than or equal to 8.
6.2. When the distance between the inner surface of the hole and the distance between the inner diameter of the hole and the inner diameter of the large and small circles is greater than or equal to 20mm or the difference between the inner diameter of the large and small circles of the hole is greater than or equal to 10 [L: the width of the strip or the unfinished area A (see Figure 7) at the joint is: less than or equal to 25mm for medium frequency; less than or equal to 12mm for super frequency and high frequency.
6.2.8 When the inner surface of the hole with a diameter greater than 200r is hardened, the width of the strip or the unfinished area 4 (see Figure 8) is: less than or equal to 25mm for medium frequency; less than or equal to 12mm for super frequency and high frequency. 8H91.3—1996
7.1 The microstructure of the structural steel and 1-carbon alloy steel parts after induction annealing and tempering shall be evaluated according to 7J3609, and the 3~7 grades are qualified.
7.7 The microstructure of carbon steel parts after induction annealing and tempering shall refer to the twelfth and eleventh level diagrams in 7HJ36003, and the microstructure of non-main parts shall be qualified according to 1~4.5.
7.3 The microstructure of non-main parts after induction annealing and tempering shall refer to the tenth and first level diagrams in 7R36M, and the microstructure of non-main parts shall be qualified according to 1~4.
7.4 The microstructure of chrome steel parts after induction annealing and tempering shall refer to the second level diagram of JB1255, and the microstructure of main parts shall be qualified according to 1-3 levels, and non-main parts shall be qualified according to 1~7 levels.
7.5 Microstructure of non-main parts shall be qualified according to 1/T 13298 The method specified in the inspection is carried out on the representative parts or simulation records of the parts. 8 Deformation
8.1 The deformation of the parts meets the requirements of the sample or process documents. Parts with excessive deformation can generally be corrected. Parts with high stability requirements can be corrected and then be subjected to stress relief adjustment. 9 Acceptance inspection
9.1 The parts shall meet the relevant indicators specified in the assembly requirements to be qualified. 9.2 Appearance quality, surface hardness, deformation, parts and parts of the equipment must be inspected. Each part shall be inspected. The rest are inspection items. The inspection items shall be noted in the process documents.
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