Steel welded pipe is referred to as welded pipe, which is made by welding common steel or steel strip after being curled and formed by machine set and die. Welded steel pipe has the advantages of simple production process, high production efficiency, more varieties and specifications, less equipment investment, but its general strength is lower than seamless steel pipe. Since the 1930s, with the rapid development of high-quality strip rolling production and the progress of welding and inspection technology, the quality of weld seams has been continuously improved, and the variety and specification of welded steel tubes have been increased. Seamless steel tubes have been replaced in more and more fields, especially in heat exchanger tubes, decorative pipes, medium and low pressure fluid pipes.
First, small-caliber stainless steel welded pipes
are produced continuously on-line, and the thicker the wall thickness is. The greater the investment in the unit and the dissolving equipment, the less economical and practical it will be. The thinner the wall thickness, the lower the input-output ratio. Secondly, the process of the product determines its advantages and disadvantages. Generally, the welded steel pipe has high accuracy, uniform wall thickness, high brightness inside and outside the pipe (the brightness of the steel pipe determined by the surface grade of the steel plate), and can be arbitrarily ruled. Therefore, it embodies its economy and beauty in the application of high precision, medium and low pressure fluids.
GB/T12770-2002 (stainless steel welded steel pipe for mechanical structure). It is mainly used for machinery, automobiles, bicycles, furniture, hotel and hotel decoration and other mechanical parts and structural parts. Its representative materials are 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb, etc.
GB/T12771-2008 (stainless steel welded pipe for fluid conveying). It is mainly used for conveying low-pressure corrosive media. The representative materials are 06Cr19Ni10, 022Cr19Ni10, 06Cr19Ni110Ti, 00Cr17, 0Cr18Ni11Nb, 06Cr17Ni12Mo2, etc.