Stainless steel seamless pipe is a kind of long steel with hollow section and no seam around it. The thicker the wall thickness of the product, the more economical and practical it is, and the thinner the wall thickness, the higher the processing cost. The technology of this product determines its limited performance. Generally, the precision of seamless steel pipe is low: uneven wall thickness, low brightness inside and outside the pipe, high length cost, and pits and black spots inside and outside the pipe are not easy to remove; Its detection and shaping must be done offline. Therefore, it shows its advantages in high pressure, high strength and mechanical structure materials.
Specification and appearance quality
A. According to GB 14975-2002 Seamless Stainless Steel Pipe, the usual steel pipe length (indefinite length) is 1.5 ~ 10m for hot-rolled steel pipe and 1m for hot-extruded steel pipe. The wall thickness of cold-drawn (rolled) steel pipe is 0.5 ~1.0 ~ 7m; ， 1.0 ~ 7m； If the wall thickness is greater than 1.0mm, it is 1.5 ~ 8m.
B, 45 kinds of hot-rolled (hot-extruded) steel pipes with diameters of 54 ~ 480mm * * * * 36 species with wall thickness of 4.5 ~ 45 mm * * *. 65 kinds of cold-drawn (rolled) steel pipes with diameters of 6 ~ 200mm * * *; The wall thickness is 0.5 ~ 2 1mm * * * 39 kinds.
C. There shall be no cracks, folds, cracks, cracks, rolling injuries, delamination and scarring on the inner and outer surfaces of steel pipes. These defects shall be completely removed (except for pipes used for mechanical processing), and the thickness and outer diameter of the removed rear wall shall not exceed negative deviation. Other minor surface defects not exceeding the allowable negative deviation may not be removed.
D, the allowable depth of the straight line. Hot-rolled and hot-extruded steel pipes with a diameter less than or equal to 140mm should not be greater than 5% of the nominal wall thickness, and the maximum depth should not be greater than 0.5mm；; Cold-drawn (rolled) steel pipes should not be greater than 4% of the nominal wall thickness, and the maximum depth should not be greater than 0.3 mm. ..
E, steel pipe ends should be cut into right angles, and deburring.