Tempering is a heat treatment process in which the seamless steel pipe is heated to a temperature below Ac1 (the temperature at which the transformation of pearlite to austenite begins during heating) after quenching, kept for a certain period of time, and then cooled to room temperature.

Anti-corrosion steel pipe generally refers to the special process of anti-corrosion treatment of ordinary steel pipes, so that the steel pipes have a certain anti-corrosion ability. Generally used for waterproof, anti-rust, acid-base, oxidation and other characteristics. The following is an introduction to the outer anti-corrosion process of steel pipes.

The inspection of steel pipes (including seamless steel pipes and welded steel tubes) generally includes: inspection of geometric dimensions and surface quality; inspection of chemical composition, mechanical properties, process properties, high and low magnification structure; non-destructive testing;inspection and length measurement and weighing of some special properties.

The application of steel pipes in marine engineering can be roughly classified into three types:

In order to slow down and prevent the corrosion and depreciation of steel pipes under the chemical and electrochemical action of internal and external media or due to the metabolism of microorganisms, it is necessary to do a good job of anti-corrosion of pipelines. In addition to the corrosion protection technology for the conveying medium, most steel pipes for conveying oil and natural gas are in a relatively complex soil environment, and the conveyed medium is also corrosive, so the inner and outer walls of the pipeline are likely to corrode.

Steel is widely used and has a variety of varieties. According to the different cross-sectional shapes, steel is generally divided into four categories: profiles, plates, pipes and metal products, and can be divided into heavy rails, light rails, large steels, medium steels, small steels, and steel cold-formed steels. , High-quality section steel, wire rod, medium and thick steel plate, thin steel plate, silicon steel sheet for electrical purposes, strip steel, seamless steel pipe, welded steel pipe, metal products and other varieties.