It is a low-alloy heat-resistant steel pipe. Belonging to alloy steel pipes. The biggest advantage of this alloy steel pipe is that it can be fully utilized. Can actively respond to the slogan of environmental protection strongly advocated by the state, which is very energy-saving. It has strong heat resistance and high chromium content, and is widely used in manufacturing automobile semi-axle sleeves and other parts. But at present, the utilization rate of p 1 1 in China is very low, and its total consumption is less than half of that in developed countries. Therefore, the utilization of P 1 1 in China will become a new field in the future.