GB/T 3086-1982 Technical requirements for high carbon chromium stainless bearing steel
Some standard content:
National Standard of the People's Republic of China
Technical Conditions for High Carbon Chromium Stainless Bearing Steels
Specification for high carbon chromium stainless bearing steelsUDC 669.14/.15
.018.2
GB 3086—82
This standard applies to hot-rolled, forged and cold-drawn round steel and steel wire for manufacturing bearing sleeves and rolling elements. 1 Classification
Steel materials are classified and coded according to the addition method and delivery status as specified in Table 1. Table 1
Hot-rolled (forged) annealed steel materials
Cold-drawn annealed round steel and copper wire
Cold-drawn polished steel and steel wire
2 Dimensions, shape and weight
2.1 Dimensions
The shape, diameter and allowable deviation, ovality and curvature of steel materials shall comply with the relevant provisions of Table 2. Table 2 Types of steel Hot rolled round steel Forged round steel Cold drawn round steel 2.2 Delivery length Diameter, m 8-~120 55-120 Relevant standards GB702-862 Group (B908871 Group GB905 821I Group According to YB2454 2.2.1 Hot rolled (forged) round steel for hot working is usually 2 to 4 m, the length of hot-rolled (forged) round steel bar for cold-drawing is 2~5m. 2.2.2 The normal length of cold-drawn round steel bar is 3~5ml. 2-2.3 The normal length of polished round steel and polished steel wire is 2~4Ⅱ. 2.2.4
Each coil of steel wire must be composed of ··whole wires, and its weight shall comply with the provisions of Table 3. Issued by the General Administration of Standards of the People's Republic of China on May 10, 1982
Implementation on March 1, 1983
Wire diameter
Steel shall not have significant torsion.
CB 3086—82
The steel wire shall not be disordered, knotted or obviously spiral in the coil. 2.4 End shape
Not less than
weight, kg
Lighter
The ends of steel should be sawn neatly, without flash, burrs or bevel exceeding half of the diameter. Gas cutting is not allowed at the ends of steel. 3 Technical requirements
3.1 Grade and chemical composition
3.1.1 Melting composition
Steel is delivered according to the melting composition. The grade and chemical composition (melting analysis) of steel shall comply with the provisions of Table 4. Table 4
9CriaMo
0.90 ~1.00
0.95 ~1.10
Permissible deviation of chemical composition of finished steel
Not too dry
%
The chemical composition of steel and steel products is allowed to be compared with Table 4 and the deviation specified in Table 5Table 5
Chemical elements
Permissible deviation, %
3.1.8 Residual elements
The residual element content in steel shall comply with the provisions of Table 6. Chemical elements
Permissible amount, not too low
17.0 ~19.0
16.0 ~18.0
0.40 ～0.70
3.2 Refining method
Steel shall be smelted in electric furnace and remelted by electroslag, or it may be smelted in non-vacuum induction furnace or vacuum induction furnace and remelted by electroslag, and the steel shall be smelted in accordance with GB 3086—82
Other smelting methods that meet the requirements of this standard may also be used by agreement. 3.3 Delivery status
The delivery status of steel products includes hot-rolled (forged) annealed (RT), cold-drawn annealed (LT) and cold-drawn polished (IM). The delivery status shall be specified in the contract.
3.4 Mechanical properties
3.4.1 The Brinell hardness HB of steel products with a diameter of less than 16mm in the annealed state shall be 197~241 (indentation diameter is 4.3~3.9mm). 3.4.2 The tensile strength of round steel and steel wire with an upper diameter less than or equal to 16mm in the annealed state shall be 60~80kgf/mm23.5 Process properties
Steel products shall be subjected to top satin inspection. Hot-rolled (galvanized) steel with a diameter of less than 60mm shall be hot forged: cold-drawn round steel or steel wire with a diameter of less than 30mm shall be cold forged. After upsetting, the specimen shall not have visible cracks, cracks, folds and bubbles. If the supplier can ensure that the upsetting is qualified, the pre-forging test may not be performed. 3.6 Acid-immersed macrostructure, fracture and tower
3.6.1 The acid-immersed macrostructure of steel shall not have visible shrinkage, bubbles, peeling, internal cracks and inclusions, and shall be inspected according to the 1st, 2nd and 3rd level diagrams attached to the "Standard Rating Diagram for Paste Carbon Chromium Stainless Bearing Steel" for central looseness, general looseness and random segregation. The qualified level shall comply with the provisions of Table 7.
Macrostructure type
Central looseness
One-stage looseness
1st level shelf
2nd level diagram
3rd level diagram
For steel with a diameter less than or equal to 30mm, the supplier may check the macrostructure on the steel. 3.6.2 The fracture of steel must be uniform and fine, without white spots, shrinkage, inclusions and overburning. If the supplier can ensure that the fracture is qualified, no fracture inspection is required. Appropriate level, not too low
Sound diameter 100mm
Diameter 1mm
3.6.3 For steel with a diameter greater than or equal to 16mm, a tower-shaped specimen should be used to inspect the hairline. The starting length of the hairline is 0.6mm, and there should be no hairline greater than or equal to 0.6mm on the specimen. If the supplier can ensure that the tower-shaped inspection is qualified, no tower-shaped inspection is required. 3.7 Annealing structure
The annealing structure of steel should be red granular with a distribution of chromium. The existence of secondary carbides is allowed, and there should be no crystalline carbide structure. The schematic diagram is shown in Figure 8 attached to the "Standard Rating Chart for High Carbon Chromium Stainless Bearing Steel". 3.8 Unevenness of crystalline carbides
Steel should be tested for unevenness of crystalline carbides and evaluated according to the 9th level chart attached to the "Standard Rating Chart for High Carbon Chromium Stainless Bearing Steel". Its qualified level should meet the requirements of Table 8.
Diameter, mm
12 ~ 40
>40~60
Qualified level. Diameter, mm
2 60 ~ 80
Qualified level, not too large
Eutectoid carbide unevenness test specimen is in heat treatment state, and its heat treatment system is: annealing temperature 1000 ~ 1050 ℃, oil drop, GB 3086--82
and tempering at 200 ~ 300 ℃. The supplier can also check on the annealed specimen. Eutectic carbide unevenness is tested at the radius of the steel. The buyer can test the worst field from the radius of the radius to the center. The qualified level is allowed to have 3 specimens in each batch of 5 specimens higher than the level specified in Table 8 by half a grade. 3.9 Non-metallic inclusions
The non-metallic inclusions of steel are evaluated according to the 4th, 5th and 6th level diagrams in the "Standard Rating Diagram for High Carbon Stainless Bearing Steel". Its content level should comply with the provisions of Table 9.
16 ~ 30
Oxides
Vegetables
Plastic silicates are rated as fluidized substances, and brittle silicates are rated as oxides
The sum of compounds and sulfides
Shapeless, non-deformed impurities
Not more than
3.10 Micropores
Round steel with a diameter not exceeding 60mm shall not have micropores. For round steel with a diameter greater than 60mm, the micropores shall not exceed the level specified in the 7th level diagram attached to the "Standard Rating Diagram for High Carbon Chromium Stainless Bearings". 3.11 Decarburization layer
3.11.1 (Forging) The total decarburization layer depth on each side of the steel shall comply with the provisions of Table 10, calculated from the actual size of the steel. Table 10
Total decarburization layer depth
Male ball diameter
15 ~ 30
> 30 ~ 50
Not larger than
Nominal true diameter
>70 ~ 100
100~120
3.11.2 The total decarburization layer depth on each side of the surface of cold-drawn round steel or polished steel wire shall not exceed 1% of the point diameter. 3.11.3 There shall be no decarburization layer on the surface of polished round steel and polished steel wire. Total decarburization layer depth
Not larger than
3.12 Surface quality
3.12.1 Steel materials should be well processed, and the surface should not have cracks, folds, rips, scars, inclusions and other defects that are harmful to use. The surface of cold-drawn steel should be clean and free of rust.
The depth of removal of harmful defects on the surface of steel for mechanical processing is calculated from the actual size: round steel with a diameter of less than 80mm and equal to 80mm shall not exceed half of the dimensional tolerance, and round steel with a vertical diameter greater than 80mm shall not exceed the dimensional tolerance; the depth of removal of harmful defects on the surface of steel for cutting processing is calculated from the nominal size: round steel with a diameter less than or equal to 80mm shall not exceed half of the dimensional tolerance, and round steel with a diameter greater than 80mm shall not exceed the dimensional tolerance. 3.12.2 Individual, non-dense rips, mechanical scratches and pits on the surface of the steel wire are allowed to exist if the depth does not exceed the provisions of Table 11. The steel wire used to manufacture rollers shall be marked on the gold scarf. Steel wire diameter
≥610
GB3086--82
Permissible depth of steel wire surface defects
For concentrated beads
3.12.3 The polished round steel and polished steel wire decay surface shall not have defects. Test method
The steel quality test method and sampling requirements shall comply with the provisions of Table 12. Table 12
Surface quality
Spark test
Chemical composition
Tensile test
Upset test
Macrostructure
Annealed structure
Eutectual carbide unevenness
Non-metallic inclusionsWww.bzxZ.net
Micropores
Debonding layer
Test method
Size, size, size, sample
For solidification
In addition to the appearance inspection of the wire, each batch of 5 coils, the length of both ends shall not be less than 250mm, and the pickling inspection shall be carried out
GB 223—B3, 81
YB35—78
GB228—76
GB 231—63
GB 233—82
CB226-77
Git1814—79
YB 17—64
(226—77
YB28—59
-63
YB15—64 Sample length 4250mm
Different branches (disks)
Different branch steel
Take one from each of the ingot head and lining
Unsupported rolled (forged steel) annealed steel
Cold drawn steel, steel wire
Different branches (disks) steel
Different branches (disks) steel
Different branches (disks) steel
Different branches (disks) steel
Different branches (disks) steel
Different branches (disks) steel
Number of samples per batch
Branch by bran
Branch by bran
C8mm 5 pieces
>8 ~16 3 pieces
1≤60mm5 pieces
>0mm3 pieces
Supplier (plate)
5 Inspection rules
5.1 Inspection and acceptance
GB3086—82
Steel materials shall be inspected and tested by the supplier's technical supervision department. 5.2 Batch rules
Steel materials shall be inspected and tested in batches. Each batch shall consist of steel materials with the same smelting furnace number, the same size, the same delivery status and the same heat treatment furnace.
Electroslag furnace according to The batch is grouped by the number of the electric cooling furnace. When the electroslag process is stable and can ensure compliance with the technical requirements of this standard, it is allowed to group by the number of the consumable furnace. However, the supplier shall provide chemical composition data according to the electroslag furnace number and indicate the number of the electric cleaning furnace on the steel. 5.3 Sampling quantity
The number of samples for steel quality inspection shall comply with the provisions of Table 12. 5.4 Re-inspection and judgment rules
When the inspection results of the items are unqualified (white spots, excluding non-metallic inclusions), the supplier shall take another sample of the same number as the initial inspection to conduct a re-inspection of the unqualified items. If there is even one sample unqualified in the re-inspection result, the batch of steel will not be accepted. However, the supplier can classify and heat treat if necessary, and then re-submit the batch for acceptance. The purchaser only needs to conduct the initial inspection during acceptance.
6 Packaging, marking and quality certificate
The packaging, marking and quality certificate of hot-rolled, forged and cold-drawn round steel shall comply with the relevant provisions of GB2101-80 "General Provisions for Inspection, Packaging, Marking and Quality Certification of Steel Shapes". The packaging, marking and quality certificate of steel wire shall comply with the relevant provisions of GB2103-80 "General Provisions for Inspection, Packaging, Marking and Quality Certification of Steel Wire".
Additional Notes:
This standard was proposed by the Ministry of Metallurgy of the People's Republic of China. This standard was drafted by Dalian Steel.
The main drafters of this standard are Liu Shuichang and Jiang Weiyu. The level mark of this standard is GB308682I4 Re-inspection and judgment rules
When the inspection result of a certain item is unqualified (except for white spots, non-metallic inclusions), the supplier shall take another sample of the same number as the initial inspection and conduct a re-inspection on the same day as the initial inspection. If one sample is unqualified in the re-inspection result, the batch of steel will not be accepted. However, the supplier can re-classify and heat treat it if necessary, and then re-submit it for acceptance. The purchaser only needs to conduct an initial inspection when accepting.
6 Packaging, marking and quality certificate
The packaging, marking and quality certificate of hot-rolled, forged and cold-drawn round steel shall comply with the relevant provisions of GB2101-80 "General Provisions for Inspection, Packaging, Marking and Quality Certificate of Steel Shapes". The packaging, marking and quality certificate of steel wire shall comply with the relevant provisions of GB2103-80 "General Provisions for Acceptance, Packaging, Marking and Quality Certificate of Steel Wire".
Additional remarks:
This standard is proposed by the Ministry of Metallurgy of the People's Republic of China. This standard was drafted by Dalian Steel!
The main drafters of the standard are Liu Shuichang and Jiang Weiyu. The level of this standard is GB308682I4 Re-inspection and judgment rules
When the inspection result of a certain item is unqualified (except for white spots, non-metallic inclusions), the supplier shall take another sample of the same number as the initial inspection and conduct a re-inspection on the same day as the initial inspection. If one sample is unqualified in the re-inspection result, the batch of steel will not be accepted. However, the supplier can re-classify and heat treat it if necessary, and then re-submit it for acceptance. The purchaser only needs to conduct an initial inspection when accepting.
6 Packaging, marking and quality certificate
The packaging, marking and quality certificate of hot-rolled, forged and cold-drawn round steel shall comply with the relevant provisions of GB2101-80 "General Provisions for Inspection, Packaging, Marking and Quality Certificate of Steel Shapes". The packaging, marking and quality certificate of steel wire shall comply with the relevant provisions of GB2103-80 "General Provisions for Acceptance, Packaging, Marking and Quality Certificate of Steel Wire".
Additional remarks:
This standard is proposed by the Ministry of Metallurgy of the People's Republic of China. This standard was drafted by Dalian Steel!
The main drafters of the standard are Liu Shuichang and Jiang Weiyu. The level of this standard is GB308682I
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