JIS G3429 Seamless steel tubes for high pressure gas cylinder

G3429 standard specifies the seamless , hereinafter referred to as the tube used for the manufacture of seamless steel gas cylinders specified in JIS B8230 and JIS B8241.

Seamless steel tubes for high pressure gas cylinder.

Standards: JIS G3429

Size (mm):
Outer Dimensions: 19.05mm ~ 114.3mm
Wall Thickness:2.0mm ~ 14 mm
Length: max 16000mm

Application: Seamless steel tubes for high pressure gas cylinder.
The main products of steel / steel grade: STH11, STH12, STH21, STH22.
Packing: Bare/bundles/crates/crate protection at the both sides of tubes or as per customers’ requirements.
Painting: as requested.

Chemical Compositions(%):
Grade C Si Mn P S Ni Cr Mo
STH11 ≤0.50 0.10-0.35 ≤1.80 ≤0.035 ≤0.035 / / /
STH12 0.30-0.41 0.10-0.35 1.35-1.70 ≤0.030 ≤0.030 / / /
STH21 0.25-0.35 0.15-0.35 0.40-0.90 ≤0.030 ≤0.030 ≤0.25 0.80-1.20 0.15-0.30
STH22 0.33-0.38 0.15-0.35 0.40-0.90 ≤0.030 ≤0.030 ≤0.25 0.80-1.20 0.15-0.30
Tolerances:
Tolerance on outside diameter: 1%
Tolerance on wall thickness: +30%
Tolerance on wall thickness disparity: Within 20% of the nominal wall thickness
Tolerance on length: >+30mm

The tubes shall be manufactured by seamless process, electric resistance welding process, or butt welding process, and those of other grades shall be manufactured by seamless process or electric resistance welding process. The tube shall be as manufactured or as cold-finished condition, or they shall be subjected to appropriate heat treatment.

The tubes shall be practically straight. and the two ends shall be at right angles to the axis of the tube. The tubes shall be free from defects detrimental to practical use.