Spring steels from VANFORGE are mainly used for the hot formed springs such as the laminated springs, coiled springs, and torsion bar springs.
Methods of manufacture
- The steels are manufactured of killed steel ingots.
- The hot rolled steels unless otherwise specified shall be supplied in the as-rolled or another as worked conditions. The Brinell hardness for the steel flats shall be generally 302 or less.
- The cold worked steels shall be made of the hot rolled steels by cold drawing, cutting, grinding or the combined these processes as specified.
Steel grades
| SUP6 | Silicon manganese steel | Mainly used for laminated spring, coiled spring and torsion bar spring |
| SUP7 | Silicon manganese steel |
| SUP9 | Manganese chromium steel |
| SUP9A | Silicon manganese steel |
| SUP10 | Chromium vanadium steel | Mainly used for coiled spring and torsion bar spring |
| SUP11A | Manganese chromium boron steel | Mainly used for large laminated spring, coiled spring and torsion bar spring. |
| SUP12 | Silicon chromium steel | Mainly used for coiled spring |
| SUP13 | Chromium molybdenum steel | Mainly used for large laminated spring and coiled spring |
Chemical composition, %
| Steel grade | C | Si | Mn | P | S | Cr | Mo | V | B |
| SUP6 | 0.56-0.64 | 1.50-1.80 | 0.70-1.00 | ≤0.035 | ≤0.035 | - | - | - | |
| SUP7 | 0.56-0.64 | 1.80-2.20 | 0.70-1.00 | ≤0.035 | ≤0.035 | - | - | - | |
| SUP9 | 0.52-0.60 | 0.15-0.35 | 0.65-0.95 | ≤0.035 | ≤0.035 | 0.65-0.95 | - | - | |
| SUP9A | 0.56-0.64 | 0.15-0.35 | 0.70-1.00 | ≤0.035 | ≤0.035 | 0.70-1.00 | - | - | |
| SUP10 | 0.47-0.55 | 0.15-0.35 | 0.65-0.95 | ≤0.035 | ≤0.035 | 0.80-1.10 | - | 0.15-0.25 | |
| SUP11A | 0.56-0.64 | 0.15-0.35 | 0.70-1.00 | ≤0.035 | ≤0.035 | 0.70-1.00 | - | - | ≥0.0005 |
| SUP12 | 0.51-0.59 | 1.20-1.60 | 0.60-0.90 | ≤0.035 | ≤0.035 | 0.60-0.90 | - | - | |
| SUP13 | 0.56-0.64 | 0.15-0.35 | 0.70-1.00 | ≤0.035 | ≤0.035 | 0.70-0.90 | 0.25-0.35 | - | |
Remarks:
- As impurities, Cu content for each grade shall not exceed 0.30%
Appearance
The steels shall be well finished and free from defects that are detrimental to practical use.
Decarburization
Steels shall be free from decarburization that is detrimental to practical use. The allowable limit for the depth of decarburization may be agreed upon between the purchaser and the manufacturer.
Inspection
- The general requirements for inspection shall conform to JIS G0303
- The test results on chemical composition, appearance, decarburization, shape and dimensions shall conform to the requirements of 4, 5 and 6 of JIS G4801
- Besides the inspection items specified in 8.2 of JIS G4801, the purchaser may specify the necessary matters among those specific inspection items as shown in the following. In this case, the purchaser shall previously agree with the manufacturer as to the inspection item, sampling method, test method and acceptance criteria.
Grain size examination conforms to JIS G0551
Macro-structure examination conforms to JIS G0553
Non-metallic inclusions examination conforms to JIS G0555
Macro-streak-flaw examination conforms to JIS G0556
Hardenability test conforms to JIS G0561
Magnetic particle examination conforms to JIS G0565
Mechanical properties test conforms to JIS Z2201, Z2241, Z2243
Marking
Each bundle of the steels shall be marked the following items. However, the hot rolled steel bar whose diameter exceeds 30mm shall be legibly marked on each product when requested. However, when approval by the purchaser, a part of the items may be omitted.
Designation of grade
Charge number or inspection number
Manufacturer’s name or its identifying brand
Product size range
Diameter: 40mm - 150mm
Length: on request
Production Process
Key clients
