Seamless steel Pipe is made of steel ingot or solid pipe blank through perforation, after a serious of manufacturing processes such as hot rolling, cold rolling or cold drawing. “seamless” means the absence of seam welds.
Seamless steel pipes are used for different applications within the oil & gas industry, and the most common types of pipes used in the oil&gas industry are (ASTM pipe specifications):
ASTM A53, A106, A333, and API 5L (types of carbon steel pipes for high and low-temperature carbon steel)
ASTM A335 Grades P5 to P91 (chrome-moly alloy steel pipes for high temperature and pressure, for refinery and power plants applications)
ASTM A312 Series 300 (stainless steel pipes in grades 304, 316, 321, 347)
ASTM A790/A928 (duplex and super duplex pipes with double ferritic and austenitic structure)
Various nickel alloys material specifications (Inconel, Hastelloy, Incoloy, Monel, Nickel 200)
Some ASTM specifications cover seamless pipes only (example ASTM A335), somes apply both to seamless and welded pipes (example ASTM A333).
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 Super Duplex S32760 Pipe |
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SEAMLESS PIPE MANUFACTURING PROCESS
1. Seamless Hot Rolling Processes
Round Pipe Billet → Heating → Perforation → Three Roll Skew Rolling, Continuous Rolling or Extrusion → Off Pipe → Sizing (Or Reducing Diameter)→ Cooling → Billet → Straightening → Water Pressure Test ( Or Flaw Detection) → Marking → Storage
2. Seamless Cold Rolling (Cold drawn) Processes
Round Pipe Billet → Heating → Perforation → Head → Annealing → Pickling → Oil (Copper) → Multi Pass Drawing (Cold Rolling) → Billet → Heat Treatment → Straightening → Water Pressure Test → Marking → Storage
SEAMLESS PIPE SIZES(dimensions and weights)
1、ASME B36.10: covers the carbon and low-alloy seamless pipes sizes between 1/8 and 24 inches
2、ASME B36.19: covers the stainless steel, duplex, nickel-alloy seamless and welded pipes
OD: 1/8”-26”(3.175 mm-660.4 mm)
Schedule: SCH20, SCH30, SCH40, STD, SCH80, XS, SCH60, SCH80, SCH120, SCH140, SCH160, XXS
