Before non-destructive testing of steel pipes, the appearance inspection of the weld should meet the requirements. The general requirements for the appearance of the steel pipe weld and the surface quality of the welded joint are as follows: The welding appearance should be well-formed, and the width should be 2mm over the groove edge of each side. The height of the fillet weld foot should conform to the design regulations, the shape should be a gentle transition. Welding joint surface: do not allow cracks, non-fusion, pores, slag, or splash existence. Edge biting shall not occur on weld surfaces of pipelines, stainless steel, and alloy steel pipelines with a design temperature lower than -29 degrees. The edge bite of the weld of other materials shall be greater than 0.5mm, the continuous edge bite length shall be no more than 100mm, and the total length of the edge bite on both sides of the weld shall be no more than 10% of the total length of the weld. The weld surface shall not be lower than the pipe surface. Weld residual high, and not more than 3mm, (welding joint group to the rear groove of the large width). The wrong edge of the welded joint should be no more than 10% of the wall thickness, and no more than 2mm. The steel pipe should be tested by water pressure, bending, and flattening, and there are corresponding requirements on the surface quality. The delivery length is usually 4-10m, and the delivery length is usually required to be fixed (or double). The specification of welded pipe is expressed by the nominal diameter (mm or inch). The nominal diameter is different from the actual one. The wall thickness of welded pipe has two kinds: ordinary steel pipe and thickened steel pipe.

Cangzhou Shenlong Pipe is specialized in the production of Seamless steel pipe, straight welded pipe, spiral steel pipe, and fittings products,, product quality control is strict, and fast delivery is the qualified supplier of PetroChina, and BP oil.