Steel pipe production technology development began with the increase of the bicycle manufacturing, oil development within the early 19th century, two world wars ships, boilers, aircraft manufacturing, after the second war thermal power boiler manufacturing, industry and therefore the development of oil and gas drilling and transportation, effectively driving the steel pipe industry within the development of types, yield and quality. Usually steel pipe in line with the assembly method, divided into seamless steel pipe and welded steel pipe two types, now mainly to introduce welded steel pipe.
Welded steel pipe is that the welded steel pipe, its production is that the tube blank (steel plate and steel belt) with a spread of forming methods to bend and roll into the desired cross-sectional shape and size of the tube tube, and so use different welding methods to weld the weld and obtain the steel pipe process. Compared with seamless steel pipe, welded pipe has the characteristics of high precision, especially the precision of wall thickness, simple main equipment, small occupation, continuous operation in production, flexible production, wide product range of unit then on.
The manufacturing process for pipes will be divided into: SSAW (Spirally Submerged Arc Welding); LSAW (Longitudinous Arc Welding); electrical resistance Welding (ERW) three.
I. the assembly process of spiral steel pipe is roughly as follows
● Raw materials of spiral steel pipe are strip coil, welding wire and flux.
● Before forming the strip after leveling, cutting, planing, surface cleaning, transportation and bending processing.
● The weld gap control device is employed to confirm that the weld gap meets the welding requirements, and also the pipe diameter, staggered edge and weld gap are strictly controlled.
● After cutting into one steel pipe, each batch of steel pipe head three to hold out strict first inspection system, check the mechanical properties of the weld, chemical composition, melting condition, steel pipe surface quality and after nondestructive inspection, make sure that the pipe making process qualified, is formally put into production.
Two, straight seam submerged arc welding pipe
Straight seam submerged arc welded pipe (LSAW) generally takes plate as material, through different forming process, adopts double-sided submerged arc welding and post-welding enlargement and other processes to make welded pipe.
The main equipment is shaping machine, pre – bending machine, forming machine, pre – welding machine, expanding machine then on. Meanwhile, there are UO (UOE), RB (RBE), JCO (JCOE) and then on. The plate within the forming mold is first pressed into U shape, so pressed into O shape, and so the interior and external submerged arc welding, welding usually at the top or the complete length of the expansion (Expanding) called UOE welded pipe, not Expanding called UO welded pipe. The plate is rolled Bending shaped, then the interior and external submerged arc welding is performed. After welding, the diameter is RBE welded tube or RB welded tube without expanding. The plate is created within the order of J-c-O-type, and after welding, the diameter is expanded to JCOE welded pipe or JCO welded pipe without expanding.
Three, straight seam high frequency welded pipe (ERW) is that the hot rolled coil after molding machine, using the electrical phenomenon and proximity effect of high frequency current, so the sting of the tube is heated and melted, under the action of the extrusion roller pressure welding to attain production.
Post time: Dec-20-2021