• Good price JISG 3444 standard thick wall round structural steel pipe

IMRI is one of the top manufacturers for structural tubes in China.Structural steel pipes are  used for civil engineering and architecture such as steel towers, scaffoldings, footing piles, foundation piles, piles for landslide suppression.If you need seamless carbon steel pipes for structure use,please feel free to contact us.


Standard JIS G3444
Steel Grade/Material STK290,STK400,STK490,STK500,STK540
OEM service Provide
Outer Diameter(OD) 1 1/2”-28”(38mm-720mm)
Wall Thickness(WT) 2.6mm-60mm
Length 5.8-16m or OEM
Packing PE,Plastic cap or bundling
Surface Treatment Bare
Section Shape Round
Technique Seamless hot rolled
Application Used as structure tubes
Sour service No
Place of Origin China
MOQ 25 ton
Transportation 1.Sea port:Tianjin Xingang port,Qingdao port,Shanghai Luojing port
→America,Europe,Africa,Middle East,India, Pakistan,Japan,Korea,

2.Land port:Alataw pass port(Пограничный пункт “Алашанькоу”)
Khorgos port(Пограничный пункт “Хоргос”)
→East Asia, Uzbekistan,Kazakhstan,Kyrgyzstan…(Train)
Erlianhot port→Mongolia(Train and Truck)
Manchuria port→Russia(Train and Truck)

Chemical Composition a)
Unit: %
Symbol of grade C Si Mn P S
STK290 0.050 max. 0.050 max.
STK400 0.25 max. 0.040 max. 0.040 max.
STK490 0.18 max. 0.55 max. 1.65 max. 0.035 max. 0.035 max.
STK500 0.24 max. 0.35 max. 0.30 to 1.30 0.040 max. 0.040 max.
STK540 b) 0.23 max. 0.55 max. 1.50 max. 0.040 max. 0.040 max.
Notes: a) If necessary, other alloy elements than those given in this table may be added.

b) For STK540, the chemical composition of tubes of wall thickness over 12.5 mm may be agreed between the purchaser and the manufacturer.

Mechanical properties
Symbol of grade Tensile strength Yield point or proof stress Weld Tensile strength Flattening resistance Bendability
N/mm2 N/mm2 N/mm2 Distance between flat plates (H) Bending angle a) Inside radius
Applicable outside diameter
All outside diameters All outside diameters All outside diameters All outside diameters 50 mm or under
STK290 290 min. 290 min. 2/3D 90° 6D
STK400 400 min. 235 min. 400 min. 2/3D 90° 6D
STK490 490 min. 315 min. 490 min. 7/8D 90° 6D
STK500 500 min. 355 min. 500 min. 7/8D 90° 6D
STK540 540 min. 390 min. 540 min. 7/8D 90° 6D
NOTE 1 In this table, D stands for the outside diameter of tube.
NOTE 2 1 N/mm2 = 1 MPa
Note a) The bending angle shall be measured from the starting point of the bend.

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