LSAW Steel Pipe Expanding
Sources: this site Click: Date: 2014-7-12 11:58:47
Expanding is one of metallurgical terminology, using the hydraulic or mechanical means pressing making the welded steel pipe expanded shaping along the radial technology.
Straight welded steel pipe expanding is the steel plate in forming mold is first pressed into a U shape, and then pressed into a O shape, and then submerged arc welding, after welding, usually at the end or full range expanding called UOE pipe, no expanding called UO welded pipe. The steel plate roll bending forming, and then submerged arc welding, after welding, expanding of RBE welded pipe or not expanding of RB welded pipe. The steel plate is sequentially forming J type -C type -O type after welding, expanding for JCOE pipe or not expanding of JCO welded pipe. The above LSAW steel pipe, UOE are the most widely used.
The longitudinally welded tube expanding first can improve the longitudinal submerged arc welded pipe body and pipe end dimension accuracy, make the welded pipe body and pipe end diameter, roundness and welded pipe at both ends of the diameter difference reaching the standard requirements, easy for on-site welding construction.
The second is to reduce the uneven deformation in the longitudinal submerged arc welded pipe forming and welding process, reduce the residual stress caused by forming and pipe welding, and improve its distribution, improve the overall mechanical properties of the welded pipe.
LSAW steel pipe through the cold diameter expanding, welded steel pipe body and pipe end diameter will increase by about one percent, the diameter, roundness and welded pipe at both ends of the diameter difference were greatly improved, the welded pipe straightness also greatly improved, pipe length of about zero point five percent shortened, the wall thickness is reduced about zero point eight percent. In the formulation of longitudinal submerged arc welded pipe technology should consider these changes, determine the system work sheet width, length and thickness, and the diameter of the pipe before expanding, in order to avoid expanding the geometry after welded steel pipe is not up to the final requirements causing unqualified.
Straight welded steel pipe expanding is the steel plate in forming mold is first pressed into a U shape, and then pressed into a O shape, and then submerged arc welding, after welding, usually at the end or full range expanding called UOE pipe, no expanding called UO welded pipe. The steel plate roll bending forming, and then submerged arc welding, after welding, expanding of RBE welded pipe or not expanding of RB welded pipe. The steel plate is sequentially forming J type -C type -O type after welding, expanding for JCOE pipe or not expanding of JCO welded pipe. The above LSAW steel pipe, UOE are the most widely used.
The longitudinally welded tube expanding first can improve the longitudinal submerged arc welded pipe body and pipe end dimension accuracy, make the welded pipe body and pipe end diameter, roundness and welded pipe at both ends of the diameter difference reaching the standard requirements, easy for on-site welding construction.
The second is to reduce the uneven deformation in the longitudinal submerged arc welded pipe forming and welding process, reduce the residual stress caused by forming and pipe welding, and improve its distribution, improve the overall mechanical properties of the welded pipe.
LSAW steel pipe through the cold diameter expanding, welded steel pipe body and pipe end diameter will increase by about one percent, the diameter, roundness and welded pipe at both ends of the diameter difference were greatly improved, the welded pipe straightness also greatly improved, pipe length of about zero point five percent shortened, the wall thickness is reduced about zero point eight percent. In the formulation of longitudinal submerged arc welded pipe technology should consider these changes, determine the system work sheet width, length and thickness, and the diameter of the pipe before expanding, in order to avoid expanding the geometry after welded steel pipe is not up to the final requirements causing unqualified.
