| How to distinguish cold rolled steel pipe from hot rolled steel pipe ?
1. From the dimension accuracy, the cold-rolled steel pipe has good size and high precision
2. From the appearance, the surface of cold-rolled steel pipe is bright, and the surface of hot-rolled steel pipe has obvious oxide scale or red rust
3. From the perspective of caliber size, the diameter of cold-rolled steel pipe is smaller than that of hot-rolled steel pipe (mainly due to different machinery, each has its own specialty) From the price point of view, cold-rolled steel pipe is 1000-2000 tons more expensive than hot-rolled steel pipe (do not be greedy for cheap) 5. From the perspective of use, hot-rolled steel pipe is used in fluid transportation, mechanical structure and other occasions where the size requirements are not high, and cold-rolled steel pipe is used in places with high requirements for precision instruments, hydraulic systems, pneumatic, etc
Generally, the outer diameter of hot-rolled seamless pipe is more than 32mm, and the wall thickness is 2.5-75mm. The outer diameter of cold-rolled seamless steel pipe can be up to 6 mm and the wall thickness can be up to 0.25 mm. The outer diameter of thin-walled pipe can be up to 5 mm, and the wall thickness is less than 0.25 mm. ?