Seamless black steel pipe has the advantages of high pressure resistance and good toughness, which determines that it has a wide range of industrial applications, such as widely used in chemical and petroleum industries.

Among the common problems of seamless pipes, wall thickness difference and eccentricity take the first place.As the name suggests, it is the difference between the maximum wall thickness and the minimum wall thickness.

The construction process of PHC pipe pile includes the following five aspects: measuring and laying out line, measuring and placing pile position, vertical pile and pile insertion, straightness control and piling.

Pickling passivation is a chemical reaction used to remove rust from seamless steel pipes surfaces. The steel pipe is fully pickled and passivated to remove all kinds of oil stains, rust, oxide scale, welding spots and other dirt, and the surface becomes uniform silver-white after treatment, which greatly improves the corrosion resistance.

The technical requirements of stainless steel pipes include surface quality, mechanical properties, corrosion resistance and process performance.

The essence of high-temperature temper brittleness of seamless pipes is generally considered to be the result of the segregation of impurity elements such as phosphorus, tin, and antimony at the prior austenite grain boundaries, resulting in the embrittlement of the grain boundaries.