Precision
stainless steel tubes are very characteristic in terms of model specifications and appearance performance. First of all, the thicker the tube wall of this type of stainless steel tube, the higher its cost performance and practicability, and the thinner the tube wall, the processing cost will be greatly reduced. In addition, the performance limitations of stainless steel pipes depend on the processing technology. Usually, the precision of seamless steel pipes is low, and the thickness of the pipe wall is uneven, the brightness of the inner and outer surfaces of the pipe is low, and the cost of sizing is relatively expensive. Pockmarks and black spots are easy to appear and are not easy to remove. In addition, the detection and shaping of precision stainless steel tubes and thick-walled tubes must be processed offline. Therefore, stainless steel pipes show sufficient advantages in the field of high-pressure, high-strength mechanical structural materials.
According to the rolling process, stainless steel pipes mainly include hot-rolled, hot-extruded, and cold-drawn (rolled) stainless steel pipes. According to the difference in the metallographic structure of stainless steel, it mainly includes semi-ferritic and semi-martensitic stainless steel pipes, martensitic stainless steel pipes, austenitic stainless steel pipes, austenitic-ferritic stainless steel pipes, etc.
According to the specifications, the specifications of stainless steel pipes are mainly based on the provisions of GB14975-94 "Stainless Steel Seamless Steel Tubes". 1m. The wall thickness of cold drawn (rolled) stainless steel pipe is 0.5-1.0mm, the length is 1.0-7m; the wall thickness is greater than 1.0mm, and the length is 1.5-8m.
There are about 45 types of hot-rolled (hot-extruded) stainless steel pipes with a diameter of 54-480mm and a total of about 36 types with a wall thickness of 4.5-45mm. There are a total of 65 types of cold-drawn (rolled) stainless steel pipes with a diameter of 6-200mm and a total of 39 types with a wall thickness of 0.5-21mm.
Defects such as cracks, folds, cracks, cracks, rolling folds, delamination, and scarring should not appear on the inner and outer surfaces of precision stainless steel thick-walled pipes. Such defects need to be completely removed (unless they are specially used for machining). And after cleaning the stainless steel pipe wall, the wall thickness and outer diameter cannot exceed the negative deviation. Some slight surface defects may not be removed as long as the allowable negative deviation is not exceeded.
The allowable depth of stainless steel straights is also required. Hot-rolled, hot-extruded steel pipes, stainless steel pipes with a diameter of less than or equal to 140mm and no greater than 5% of the nominal wall thickness, and a depth of less than or equal to 0.5mm; Equal to 0.3mm.
The last thing to note is that precision stainless steel thick-walled tubes need to be cut at right angles at both ends before application, and the burrs in the tube wall should be removed.
