Difference between erw and dsaw pipes


High-frequency straight seam welded pipe (ERW) production process is easy, a single production specifications, using resistance welding and high frequency welding process. Double submerged arc welded straight seam steel pipe(dsaw) production technology was used JCOE molding process, molding process complex, high-frequency welded pipe forming efficiency relative to the low manufacturing cost is higher than the high-frequency vertical seam welded steel pipe.


Straight seam steel pipe is with a weld, the weld long or short, but it must be a weld, according to the length of the plate, and now a national high-frequency welded steel pipe welds can be done 14 meters, double submerged arc welding a straight seam steel pipe welds can be done up to 12.8 meters, nails welded steel plate width restrictions due to a weld can produce up to 2.2 meters.


Straight seam steel pipe testing broadly is divided into: chemical composition, tensile test, bending test, flattening test, guided bend test, hydraulic testing, ultrasonic testing resistance welded steel pipes, submerged arc welded pipe has ultrasonic testing, eddy current testing, ray detection testing. Internal and external surfaces of steel pipe should be smooth, not allowed to have been folded, cracks, delamination, lap welding, breaking arc, burn, and other depth exceeds the wall thickness deviation defects. Depth does not exceed the permitted deviation of fresh local defects exist.


High frequency welded pipe used for conveying water, gas, air, oil and heating steam, suitable for low pressure fluid pipe, structural steel. Double submerged arc welded straight seam steel pipe used in large-span Wangjiagongcheng, water, gas pipelines, construction, electrical engineering, mechanical, bridge beams, steel structure, foundation piling and other facilities.

Post time: Oct-16-2019