Seamless Steel Pipe

Baotou Steel DN150 DN250 DN350 DN450 seamless steel line pipes produced by Baotou Steel can be coated with any kind of internal and external anti-corrosion coatings like 3PE,3PP,FBE,3LPE,3LPP etc.We can pack the seamless steel pipes according to your requirements like beveled ends,black painting,plastic caps,etc.Pipes with diameter between 38mm-457mm of any steel grade canbe produced.

Pipeline steel pipes are used to transport oil, gas and water extracted from the ground to petroleum and natural gas industrial enterprises through pipeline pipes. Pipeline pipes include seamless pipes and welded steel pipes, and their pipe ends have flat ends, threaded ends and socket ends. Its connection methods include end welding, clamp connection, socket connection, etc.

Application: It is used for the transportation of gas, water and oil in the petroleum and natural gas industries.

API SPEC 5L(Pipeline Tube Specification), compiled and released by the American Petroleum Institute, is applicable worldwide. The main materials of this pipe are L245, L290, L360, L415, L480, GR.B, X42, X46, X56, X65, X70, X80, X100 and other steel grades.

Types of tempering

According to the different performance requirements of pipeline steel pipes in GB/T9711.1, tempering can be classified into the following types based on their tempering temperatures:

【 1 】 Low-temperature tempering (150-250 degrees)

The microstructure obtained through low-temperature tempering is tempered martensite. The purpose is to reduce the quenching internal stress and brittleness of quenched steel while maintaining its high hardness and high wear resistance, so as to avoid cracking or premature damage during use. It is mainly used for various high-carbon cutting tools, measuring tools, GB/T9711.1 pipeline steel pipes, rolling bearings and carburized parts, etc. The hardness after tempering is generally HRC58-64.

【 2 】 Medium-temperature tempering (250-500 degrees)

The tissue obtained through medium-temperature tempering is tempered Troostite. The aim is to achieve high yield strength, elastic limit and relatively high toughness. Therefore, it is mainly used for the treatment of various GB/T9711.1 pipeline steel pipes and hot working dies, and the hardness after tempering is generally HRC35-50.

【 3 】 High-temperature tempering (500-650 degrees)

The microstructure obtained through high-temperature tempering is tempered sorbite. Conventionally, the heat treatment that combines quenching with high-temperature tempering is called quenching and tempering treatment. Its purpose is to obtain comprehensive mechanical properties with good strength, hardness, plasticity and toughness. Therefore, it is widely used in important structural parts of automobiles, GB/T9711.1 pipeline steel pipes, machine tools, etc., such as connecting rods, bolts, gears and shafts. The hardness after tempering is generally HB200-330.