Our coiled steel line pipe is continuously milled and coated in-line. We source long seam as well as spiral welded pipe to meet customer demands. We have close relationships with double submerged arc welded (DSAW) pipe mills around the world.
Pipes are mostly sold by SRL (single random length) or Double Random Length (DRL). Welded pipe does NOT have a weld seam inside or outside. It just means a pipe that has been produced by ERW process. PPGI Steel Sheet Manufacturer.
A53 grade B is the most common specification of welded pipe. A106 B is the most common seamless pipe specification. Steel pipe is sold by nominal pipe size and schedule.
Some of the big names in the pipe industry are US Steel, ArcelorMittal, Nippon Steel, Nucor Corp, Hyundai Steel, ThyssenKrup, Vallourec, Hebei Iron and Steel Group, Posco, Jiangsu Shagang, Ulma Piping, Shultz USA and Webco etc. Steel pipe is made by mills all around the world and traded in different countries. It is useful in applications with acids, brines, sulphur water, sea water and with hologen salts.
Type 316SS pipe is much more resistant to pitting than other chromium nickel alloys due to the addition of 2-3% molybdenum. 304SS pipe has maximum carbon content of 0.08%. Pipe’s corrosion resistance can also be enhanced with corrosion resistant pipe coating.
Steel Pipe Coating and Lined Steel Pipe. Standard weight of zinc is 1.8 oz per sq ft. Galvanized pipes provide good protection to the pipe inside and out. Zinc is usually applied by a hot dipping process where pipe is submerged in a molten bath of zinc solution.
Most common finish on the metal pipe is lacquer coating that prevents corrosion and protects the pipe from weather. Steel pipe is identified by paint stencil or stamped marking on the pipe itself or by a tag attached to it. Hence it is important to identify steel pipe markings.
Steel pipe is available in different classification, grade, weight, schedule number etc. Picture below shows different steel pipe end finishes; It is also available in Single Random Length (SRL) which could be anywhere from 17 ft to 24 ft. Double Random Length (DRL) refers to pipes that is at least 37 ft long and up to 44 ft.
Generally steel pipe is supplied in 21 ft lengths. Most common seamless pipe is A106B. Seamless pipe is available in the following specifications;
Seamless pipe goes through various finishing operations such as straightening, inspection, hydro testing and imaging. There are two main methods of producing seamless pipe; In simple terms the seamless pipe is produced by piercing a solid round billet leaving behind a hollow seamless pipe.
Seamless pipe has no longitudinal seam or weld when compared to ERW pipe. Seamless pipe is produced in sizes from 1/8 to 36″ nominal. Most common spec for welded pipe is A53 and API 5L.
The welded pipe is heat treated, inspected and hydro tested. These methods raise the temperature of the steel edge to 2600 deg F for effective welding.