The characteristics of the stainless steel seamless pipe: the thicker the wall thickness of the product, the more economical and applicable it is, the thinner the wall thickness, its processing cost will rise significantly; secondly, the process of the product determines its Restricted performance, low precision of ordinary seamless steel pipes: uneven wall thickness, low brightness of the inner surface of the pipe, high cost of sizing, and there are pits and black spots on the inner surface that are not easy to remove.
Its detection and shaping must be done offline. Therefore, it shows its superiority in terms of high pressure, high strength, and materials for mechanical construction. Varieties of stainless steel pipes: hot-rolled, hot-extruded and cold-drawn (rolled) stainless steel pipes. According to the metallographic structure of stainless steel, it is divided into semi-ferritic semi-martensitic stainless steel pipe, martensitic stainless steel pipe, austenitic stainless steel pipe, austenitic-ferritic iron stainless steel pipe, etc.
Stainless steel pipe specifications and appearance quality: According to the rules of GB14975-94 "Stainless Steel Seamless Steel Tubes", the steel pipes usually have a length (indefinite length) of hot-rolled steel pipes of 1.5~10m, and hot-extruded steel pipes equal to and greater than 1m. Wall thickness of cold drawn (rolled) steel pipes 0.5~1.0mm, 1.0~7m; for wall thickness greater than 1.0mm, 1.5~8m. There are 45 types of hot-rolled (hot-extruded) steel pipes with a diameter of 54-480mm; a total of 36 types with a wall thickness of 4.5-45mm. There are 65 kinds of cold drawn (rolled) steel pipes with a diameter of 6~200mm and 39 kinds with a wall thickness of 0.5~21mm.
The inner surface of the steel pipe must not have cracks, folds, cracks, cracks, rolling, delamination and scarring defects. These defects should be completely eliminated (except for pipes for machining). After cleaning, the wall thickness and outer diameter must not be changed. Go beyond negative bias. Other minor surface defects that do not exceed the allowable negative bias can not be eliminated, and the straights allow depth. Hot-rolled and hot-extruded steel pipes, with a diameter less than and equal to 140mm, not greater than 5% of the nominal wall thickness, and the maximum depth is not greater than 0.5mm; cold drawn (rolled) steel pipes are not greater than 4% of the nominal wall thickness, and the maximum depth is not greater than 0.3 mm.