JIS G3456 STPT370 Carbon Steel Pipes
Description
JIS G3456 STPT370 Carbon Steel Pipes
Standard:JIS G3456
Carbon Steel Pipes for High Temperature Service
JIS G3456 STPT 370 Carbon Steel Pipes mainly used for piping at a temperature over 350℃.
JIS G3456 STPT 370 Carbon Steel Pipes Quick Details
Manufacture:Seamless or electric resistance welding process
Out Dimensions: 14mm-508mm
Wall Thickness: 2mm-60mm
Length: Fixed(6m,9m,12,24m) or normal length(5-12m)
Ends: Plain End, Beveled End, Treaded
Method of Manufacture
(1)JIS G3456 STPT 370 Carbon Steel Pipes are manufactured from coarse-grained killed steel by the seamless or electric resistance welding process
(2)When required by the purchaser, the pipe may be furnished with the bevel end.
Heat treatment
| Grade | Hot finished seamless steel pipe | Cold finished seamless steel pipe | Hot finished electric resistance welded steel pipe | Electric resistance welded steel pipe other than hot finished |
| STPT370 | As manufactured. However, low temperature annealing or normalizing may be applied, as necessary. | Low temperature annealed or normalized. | As manufactured. However, low temperature annealing or normalizing may be applied, as necessary. |
Low temperature annealed or normalized. |
Chemical Composition of JIS G3456 STPT 370
| Grade | Chemical Composition % | ||||
| C | Si | Mn | p | S | |
| STPT 370 | 0.25 max. | 0.10~0.35 | 0.30~0.90 | 0.035 max. | 0.035 max. |
Mechanical Properties of JIS G3456 STPT 370
| Letter symbol of grade | Mechanical Properties | |||||
| Tensile strength | Yield strength | Elongation % | ||||
| kgf/m㎡ {N/ m㎡} | kgf/m㎡ {N/ m㎡} | No.11 and No.12 test pieces | No. 5 test pieces | No. 4 test piece | ||
| Longitudinal | Transverse | Longitudinal | Transverse | |||
| STPT370 | 38 {373}min | 22{216} min | 30 min | 25 min | 23 min | 28 min |
Appearance
(1)The pipe are practically straight, and its both ends shall be at a right angle to its axis.
(2) The inside and outside surfaces of the pipe shall be well-finished and free form defects that are detrimental to practical use.
Dimensions Tolerance of JIS G3456
| Division | Tolerances on outside diameter | Tolerances on wall thickness | Tolerance on deviation in wall thickness |
| Hot finished seamless steel pipe |
Up to 50 mm 【0.5mm | ≤Up to 4 mm 【0.5mm |
Up to and incl. 20 % of wall thickness |
| 50mm and over, up to 160mm 【1% |
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| 160mm and over, up to 200mm 【1.6mm |
≤4mm and over 【12.5% |
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| 200mm and over 【0.8% | |||
| However, for pipes 350mm and over in diameter, the length of circumference may substitute as a basis for tolerances, In this case, the tolerances shall be 【0.5%. |
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| Cold finished seamless steel pipe and electric resistance welded steel pipe |
Up to 40mm 【0.3mm | ≤Up to 2 mm 【0.2mm |
– |
| 40mm and over 【0.8% | ≤2mm and over 【10% |
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| However, for pipes 350mm and over in diameter, the length of circumference may substitute as a basis for tolerances. In this case, the tolerances shall be 【0.5% |
Testings
(1)Chemical analysis
(2)Tensile Test
(3)Flattening Test
(4) Bending Test
(5) Hydrostatic Test or Nondestructive Examination