JIS G3444 Black Steel Pipes STK290 STK400 STK490 In Engineering Architecture Piles Construction

Black Steel Pipes JIS G3444 PIPES STK290 STK400 STK490 Used In Engineering, Architecture, Piles, Construction

Product Description

Mechanical Performance Orientation: Similar to ASTM A500, it uses mechanical properties (tensile strength) as the primary basis for grading and acceptance, with relatively lenient requirements on chemical composition. The grade directly reflects its minimum tensile strength.

Main Grades: The standard specifies several grades, the most common being:

STK400

STK490

STK540

STK500 (for square and rectangular tubes)

“STK” is an abbreviation for “Steel Tube Kozo-yo (for structural use)”.

The number represents the minimum tensile strength value (in MPa) of that grade of steel tube. For example, STK490 indicates that its tensile strength is not less than 490 MPa.

Manufacturing Process: Primarily produced by cold forming or hot forming processes, where steel strip is rolled and welded (ERW). Heat treatment is typically not performed after forming.

Cross-sectional Shape: Includes circular, square, and rectangular sections; typical structural hollow profiles.