JIS G3445 STKM 15A Drawn Over Mandrel Steel Tube Seamless And Electric Resistance 

Product Name:Carbon steel tubes for machine structural purposes

Appllication: 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%

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.

Note: For the finished seamless steel tubes the tolerances No.1 shall be applied.

The tolerances on the tube length shall be in the range of 0 to+50mm.However,when tolerances outside this range are especially required,agreement shall be made between the purchaser and manufacturer.

(DOM)Drawn Over Mandrel :

The first stages of manufacturing : ERW ,but in the finishing stages : Entire flash weld is removed and the tube is clod drawn over a mandrel.which provides the tube with a better  dimensional tolerances,good surface finish and the strongest weld strength achievable.