Gr.C Dn300 Astm A139 325 MM Spiral Seam Welded Pipe Hollow Section

Gr.B Gr.C Astm A139 Spiral Welded Steel Hollow Section Ssaw Steel Pipe

SSAW spiral welded pipe nominal diameter, also known as the average outside diameter.This is because the wall of the metal pipe is very thin, the outer diameter of the pipe and the inner diameter of the pipe are almost the same, so take the average of the outer diameter of the pipe and the inner diameter of the pipe as the diameter of the pipe.SSAW spiral steel pipe used in water engineering, petrochemical industry, chemical industry, electric power industry, agricultural irrigation, urban construction, is one of the 20 key products developed in China.For liquid transportation: water supply and drainage.For gas transportation: gas, steam, liquefied petroleum gas.For structural use: as a pile pipe, as a bridge;Piping for wharves, roads, building structures, etc.

The pressure reduction of the extrusion roller is adjusted so that the weld clearance is controlled at 1~3mm and both ends of the welding joint are flush.Main technological features of spiral steel tube:In the forming process, the steel plate deformation uniformity, the residual stress is small, the surface does not produce scratches. The pipe shall be substantially round. The outside circumference of the pipe shall not vary more than 1.0%, but not exceeding ¾ in. from the nominal outside circumference based upon the diameter specified, except that the circumference at ends shall be sized, if necessary, to meet the requirements of Section 15.

Finished pipe shall be commercially straight. When specific straightness requirements are desired, the order should so state and be agreed upon between the purchaser and the manufacturer.Pipe shall be furnished with an angle cut of 90° or beveled ends as specified. All burrs at the ends of pipe shall be removed. When pipe ends have to be beveled for the welding, the ends shall be beveled on the outside to an angle of 35° with a tolerance of ± 2½° and with a width of root face 1/16" ± 1/32".The minimum wall thickness at any point shall be not more than 12.5% under the nominal wall thickness.