JIS G3445 STKM 15A Drawn Over Mandrel Steel Tube Seamless And Electric Resistance
Product Name:Carbon steel tubes for machine structural purposes
Appilication: Machine Auto competent Furniture Bicycle Mechanical parts Mechanical Elements machine elements
1.Grade
STKM 11A
STKM 12 (ABC)
STKM 13(ABC)
STKM 14(ABC)
STKM 15(AC) etc
Standard JIS G3445
2.OD:4-60mm,Wall thickness:0.5-7mm
3.Characteristic:The tubes are high precision in tolerance
4.Kindly advise heat treatment requirement if any.
HR CW SR A N HF
HR:hot rolled CW:cold worked SR:stress relieved A:annealed N:normalized HF: hot formed.
5.STKM 15A Chemical composition % max:
C:0.25-0.35 S:0.35 Mn:0.30-1.00 P:0.04 S:0.04
Mechanical properties:min
Tensile strength 470Mpa Yield Strength:275 Mpa Elongation:22%
Use in Cross member,Frame side member,Axle tube,Valve locker shaft, Steering system, Extract tension tube
Tolerances on OD
Division
Tolerance on OD
No.1
under 50mm ±0.5mm
50mm or over ±1%
No.2
under 50mm ±0.25mm
50mm or over ±0.5%
No.3
under 25mm ±0.12mm
25mm or over to and excel.40mm ±0.15mm
40mm or over to and excel.50mm ±0.18mm
50mm or over to and excel.60mm ±0.20mm
60mm or over to and excel.70mm ±0.23mm
70mm or over to and excel.80mm ±0.25mm
80mm or over to and excel.90mm ±0.30mm
90mm or over to and excel.100mm ±0.40mm
100mm or over ±0.50%
Note:1. For hot finished seamless steel tube, the outside diameter tolerance No.1 shall be applied.
2.The tolerance on outside diameter of quenched and tempered tubes shall be as agreed upon by the purchaser and manufacturer.
Tolerances on WT
Division
Tolerance on WT
No.1
under 4mm +0.6mm -0.5mm
4mm or over +15%-12.5%
No.2
under 3mm ±0.3mm
3mm or over ±10%
No.3
under 2mm ±0.15mm
2mm or over ±8%
Note: For the fiished seamless steel tubes the tolerances No.1 shall be applied.
The tolerances on the tube length shall be in the range of 0to+50mm.However,when tolerances outside this range are especially required,agreement shall be made between the purchaser and manufacturer.