Q345B Rectangular Tube

Implementation Standards

1. GB/T3094-2000 (national standard) cold pressure special-shaped rectangular tube
2.Cold bending hollow steel for 2.GB/T6728-2002 (national standard) structure
3.ASTM A500 (American Standard) structure for cold forming of circular cross-section and special-shaped welded rectangular pipe and seamless rectangular tube
4.EN10219-1-2006 (European standard) cold formed welded hollow structure profiles of non alloy and fine grain
5.JIS G 3466 (day standard) rectangular tube for general construction

Applicable Scope

The general square tube is mainly used to make water wall tube, boiling water pipe, superheated steam pipe, superheated steam pipe used for locomotive boiler, large, small smoke pipe and arch brick tube, etc.

Chemical Composition

Chemical composition of the brand (%)
C Si Mn P S
Not greater than

St35 ≤0.18 0.17-0.37 0.35-0.65 0.035 0.035

St37.4(10#) ≤0.18 0.17-0.37 0.35-0.65 0.035 0.035

St45(20#) ≤0.25 0.17-0.37 0.50-0.80 0.035 0.035

St55(35#) ≤0.22 ≤0.55 ≤1.50 0.035 0.035

St52(16Mn) ≤0.20 ≤0.55 ≤1.50 0.035 0.035

CK45 0.42-0.50 0.17-0.37 0.50-0.80 0.035 0.035

Mechanical Property

Performance standard of supply state brand products
tensile strength
6B
MPa yield point
6S

δ5
%
After the stress annealing BKS is finally cold formed,
Chemical composition and properties of square tube plastic small square tube, in non oxidation
The medium is annealed in the atmosphere. St35 340-470 = 235 = 33
St45 440-570 = 255 = 32
St52 490-630 = 355 = 29