What's the difference between straight steel pipe and seamless steel pipe?
The welded pipe is made of rolled steel plates, and small ones are straight welded, and big ones are spiral welded. Because the welded pipe has weld, the mechanical performance of weld is poor, so its applicable range is limited, but its price is cheap. Significant difference is that there are welded pipe, seamless steel pipe is not, of course, the welded pipe treatment of good, layman do not see the difference.
Seamless steel pipe and welded pipe are separated because of different production process. Seamless steel tubes include hot rolling, cold rolling, cold drawing, and other rare, such as cold extrusion.
Observe whether there is weld seam. Welded pipe without treatment, there are obvious weld, there are bulges, like scars. A better point will shave off the weld, but there is a distinct difference between the eye and the eye. Also a small number of pipe will be processed after cold rolling, surface roughness and accuracy are relatively high, may be counterfeit seamless pipe sales. Careful observation will still show that the pipe wall will have a continuous spiral, metal luster slightly brighter, that is, the original welding seam, metallographic structure and other parts of the difference. To tell the truth, the layman would have to observe that it might be a little difficult.
