Big straight seam welded pipe: also called welded steel pipe, is with steel plate or steel belt after bending shape, the electrical model is 0317. Check 8517611 standard, and then made by high-frequency welding, submerged arc welding.It is divided into straight seam welded pipe and spiral welded pipe according to the form of weld.It can be divided into general welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe, idler pipe, deep well pump pipe, automobile pipe, transformer pipe, electric welding thin-wall pipe, electric welding special-shaped pipe and spiral welded pipe, large diameter welded pipe and so on.
Our company mainly produces large-diameter double-sided submerged arc straight Welded steel pipe with specifications of 351-1050mm*8-30mm and length of 8-14m. Various non-model wall thickness specifications can reach 1000 kinds. The production port is strictly in accordance with GB/T 3091-2001-welded steel pipe for low pressure liquid delivery.
Large-diameter straight-seam steel pipe process
Large-diameter straight-seam steel pipe mainly to double-sided buried arc welding production process, products by bending, seam, internal welding, external welding, straightening, flat head and other multi-process, to meet the relevant standards.
Weight formula for large-diameter straight-seam steel pipe
[(OD - Wall Thickness) * thickness] * 0.02466 = kg / m (per meter weight)
According to GB/T3091-2008 "Low pressure fluid transport welding steel pipe" standard, the internal and external surface of the steel pipe should be smooth, do not allow folding, cracks, layering, welding, arc break, burn and other depth beyond the wall thickness deviation allowed to have a depth not more than the wall thickness deviation of other local defects.
The steel pipe shall be subject to mechanical property test, tensile test, bending test, flattening test, guided bending test and hydraulic test, and shall meet the requirements specified in the standard. The steel pipe shall be able to bear a certain internal pressure, the maximum test pressure is 5.05mpa, and the holding time shall not be less than 5S. During the test, the steel pipe shall not leak. It is allowed to use ultrasonic flaw detection or eddy current flaw detection instead of hydraulic test for resistance welded steel pipe. Ultrasonic flaw detection or radiographic inspection is allowed to replace hydraulic test for submerged arc welded steel pipe.
Wide straight seam steel pipe USES:
1. Petrochemical: crude oil, refined oil, petrochemical raw materials and finished products conveying pipe and oil field pipe network.
2. Natural gas: submarine and onshore long-distance pipelines, natural gas receiving station pipelines, gas fields and urban natural gas pipelines.
3. Coal: transportation of coal, coal water slurry, etc.
4. Structure: steel pipe pile curtain for wharf, steel pipe for high-rise buildings and Bridges, steel pipe for offshore platforms.
5. Other categories: water supply;The power plant takes the drainage line and the high pressure line.