Want to know what technology is used for seamless steel pipes?

Fujin Iron and Steel2021-09-29

Generally, seamless steel pipes are used to transport water, gas, oil and other fluid pipes and to make various structural parts, and their mechanical functions such as tensile strength, yield strength and elongation should be sampled. The conveying fluid pipe is generally operated under pressure, and it is also required to do water pressure experiment and flaring, flattening, crimping and other technological function experiments. Regarding the large-scale long-distance crude oil, refined oil, and natural gas pipeline steel pipes, the requirements for carbon equivalent, welding function, low-temperature impact toughness, stress corrosion under severe corrosive conditions, corrosion fatigue and strength under corrosive environments have been increased.

Generally, boiler tubes are used to make superheated steam tubes and boiling water tubes for boilers of various structures. High-pressure boiler tubes are used for superheated steam tubes of high-pressure or ultra-high-pressure boilers, heat exchangers and pipelines for high-pressure equipment. The above-mentioned steel pipes for thermal equipment are all operated under different high temperature and high pressure conditions, and outstanding appearance conditions, mechanical functions and process functions should be ensured. Generally, it is necessary to check its mechanical functions, and do flattening and water pressure tests. The high-pressure boiler tube also requires the inspection of grain size and more stringent non-destructive testing.

Seamless steel pipes for machinery must have high dimensional accuracy, outstanding mechanical functions and appearance according to the requirements of use. For example, the bearing tube requires high wear resistance, uniform arrangement and strict internal and external diameter service. In addition to general mechanical function inspection items, low power, fracture, annealing arrangements (spheroidization arrangement, mesh light, ribbon), non-metallic inclusions (oxides, sulfides, dots, etc.), Carbon layer and its hardness target and other experiments.

High-pressure seamless steel pipes used in the fertilizer industry often transport chemical media (such as synthetic ammonia, methanol, urea, etc.) in a corrosive environment with a pressure of 2200~3200Mpa, an operating temperature of -40°C to 400°C. High-pressure seamless steel pipes used in the fertilizer industry should have strong corrosion resistance, outstanding appearance and mechanical functions. In addition to mechanical function, flattening and water pressure tests, corresponding simplified corrosion tests, management and more stringent non-destructive tests should be done according to different steel grades.

Petroleum and geological drilling steel pipes operate in harsh environments of high pressure, alternating stress, and corrosiveness, so they should have a high level of strength, and be able to resist abrasion, torsion, and corrosion. According to different steel grades, tensile strength, yield strength, elongation, impact toughness and hardness should be tested.

Regarding the casing, tubing and drill pipes used in oil wells, it is specifically divided into steel grades, categories, and additional technical conditions that are suitable for different environments and geological conditions and are selected by users to meet different special needs. This article was released by Tianjin Rui Delong Steel. If reprinted, please clarify the source.

In addition to mechanical function and water pressure tests, various stainless heat-resistant and acid-resistant pipes used in chemical, petroleum cracking, aviation and other machinery industries must also be specially used for intergranular corrosion tests, flattening, flaring and non-destructive