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JIS G3444 pipe indicates welded or consistent carbon steel tubes for general auxiliary purposes.
The specification of JIS G3444 pipe are:
Grade: STK290, STK400, STK490, STK500, STK540
Outer diameter: 33.4-660mm
Wall thickness: 2.1-22mm
Japanese Industrial Standards (JIS) developed by the organization apply to a wide variety of industrial services and technologies such as automobiles, metallurgy, ships and medical equipment. The JIS G3444 pipe can be applied in civil designing, engineering, steel towers, frameworks, swaggers, heaps for concealment of avalanche and different structures