CHARACTERISTICS OF WELDED STEEL PIPE

The general strength of welded steel pipe is lower than that of seamless steel pipe. With the continuous improvement of the quality of the weld, more and more varieties of welded steel pipe specifications, and in more and more fields instead of seamless steel pipe. At present, in the oil and gas pipeline tube with spiral seam submerged arc welding (SSAW), double submerged arc welded pipe (LSAW) and high-frequency welded pipe (ERW). Double submerged arc welded pipe according to the different forming method is divided into UOE, RBE and JCOE steel pipes. 1 spiral seam submerged arc welded pipe spiral seam submerged arc welded pipe production, the width of the plate coil to determine the circumstances, generally suitable for small batch production of many varieties. Spiral seam submerged arc welded pipe can produce larger diameter, and some can reach more than 2540 mm, but due to the limitation of the processing technology, the thickness of the wall can be made relatively thin, generally the maximum is 14mm.

2 UOE steel pipe

UOE pipes are considered to be the best in the quality and reliability of the welded pipe market. Submarine pipeline, river crossing section, large drop lot, after the earthquake zone and active fault location, after a lot of swamp and difficult to repair the lot, the pipeline designers still insist on the use of UOE steel pipe. UOE steel pipe production unit due to high prices, is still owned by a small number of countries.

UOE steel pipe is formed by stamping and rolling, which is formed by submerged arc welding. The production method is suitable for large scale production of the same caliber, but its caliber is restricted by the wide plate width, the UOE steel pipe is made by the stamping process. Pipeline in the vast majority of cases, the thickness of the choice is determined by the rigid conditions. Usually cases, low grade and high thickness, the thickness can be above 20mm, and some even up to 28 mm or more, which is spiral pipe can’t meet. UOE steel pipe production is very high, in the world in the situation of excess production capacity.

3.JCOE steel pipe

JCOE steel pipe is the first creation of Taiwan, a welding steel pipe production process. Its production process is the first in the hydraulic press to press the J shape, on both sides of the pressure side, after a number of pressing into a C shape, and finally through a circular die pressed into a circular. This pipe is used in submerged arc welding, such as after welding process is known as the JCOE steel pipe, the pipe is not up process called JCO steel pipe. Up tube, not only to improve the geometry, and the elimination of internal stress. The quality of JCOE steel pipe is similar to that of UOE steel pipe, and the production line price is much lower than that of UOE unit, but its production efficiency is lower than that of UOE unit.

4.RBE steel pipe

RBE steel pipe is through the pressure side, roll system (with three or four roller rolling Zheng Ji), the use of submerged arc welding. If you do not take up tube shaped plastic known as RB steel pipe, to take up plastic is called RBE steel pipe, after the tube to eliminate the internal stress, and its quality is similar to UOE. RBE after the production of steel to eliminate the internal stress, and its quality is similar to the UOE. RBE steel pipe production line is lower than the price of UOE, and its productivity is also low.