Welded Duplex Large Steel Pipe
Usage: Used for low pressure liquid delivery, such as water, gas, and oil. General, Hydraulic System, Constructural, Decorative/Ornamentalssss
Process:
TIG (DIN 17455; 17457) - tungsten inert gas welding, used for water piping, gas supply pipes and and pipes for the food industry
MIG - metal inert gas welding.
PAW – plasma arc welding.
ERW (Electric Resistance Welded)
HFI (High Frequency Induction)
EFW (Electric Fusion Welded Tube)
LSAW (Longitudinal Submerge-arc Welded) UO(UOE),RB(RBE),JCO(JCOE)
DSAW (Double Submerged arc welded)
SAW (Spiral Welded)
SSAW (Spiral Submerged-arc Welded)
ERW HFI , EFW, LSAW, DSAW:
GB/T3091 Welded steel pipe for low pressure liquid delivery
GB/T9711 Petroleum and natural gas industries--Steel pipe for pipelines
Application of Welded Duplex Large Steel Pipe, standards and regulations:
| Application | GOST | International standard |
| General purpose pipes | GOST 9940-81, GOST 9941-81 | ASTM A312 |
| Heat-exchanger pipes | GOST 9941-81 (gauge pipes) | ASTM A213, DIN 17458-85, ASTM A268. ASTM A269 |
| Instrument piping systems | GOST 19277-73, GOST 10498-82, GOST 14162-79, | DIN 17458-85 |
| Boiler pipes | TS 14-ZR-55-2001, TS 14-3-460-75, TS 14-ZR-197-2001 | |
| Furnace pipes | GOST 9940-81, GOST 9941-81, m/s10H23N18, 15H25T, | ASTM A312, m/s TP310S |
Size:
ERW Electric resistance welding, HFI, EFW:
Outer Diameter: 6mm-610mm (1/16"-24")
Wall Thickness: 0.3mm-22mm
Length: 0.5mtr-20mtr
LSAW, DSAW:
Outer Diameter: 219mm-1820mm
Wall Thickness: 5.0mm-50mm
Length: 6mtr-18mtr
SAW Submerged arc welding, SSAW:
Outer Diamter: 219.1mm - 4064mm (8" - 160")
Wall Thickness: 3.2 mm - 40mm
Length: 6mtr-18mtr
End: square ends (straight cut, saw cut, and torch cut). or beveled for welding, beveled,
Surface: Lightly oiled, Hot dip galvanized, Electro galvanized, Black, Bare, Varnish coating/Anti rust oil, Protective Coatings (Coal Tar Epoxy, Fusion Bond Epoxy, 3-layers PE)
Packing: Plastic plugs in both ends, Hexagonal bundles of max. 2,000kg with several steel strips, Two tags on each bundle, Wrapped in waterproof paper, PVC sleessve, and sackcloth with several steel strips, Plastic caps.
Test: Chemical Component Analysis, Mechanical Properties (Ultimate tensile strength, Yield
strength, Elongation), Technical Properties (Flattening Test, Bending Test, Blow Test, Impact Test), Exterior Size Inspection, Hydrostatic Test, X-ray Test.
Mill Test Certificate: EN 10204/3.1B
Third party inspection: SGS, BV, Lloyds etc.
