Cold treatment process of seamless tubes

In the production of carbon steel seamless tubes, cold treatment processes are usually used to improve the strength and hardness of the material. The following is the general seamless tube (SMLS) cold treatment process.

1. Water quenching

In the manufacturing process of seamless tubes, water quenching is a common quenching method used to quickly cool seamless tubes to increase their hardness. This is usually part of a quenching and tempering process, where quenching is used to increase hardness and tempering is used to restore some toughness. It should be noted that water quenching can be performed immediately after the heating stage or before tempering. Process conditions for the entire quenching and tempering process, such as temperature and duration, will vary based on the specific carbon steel alloy, seamless tube size and application requirements.

2. Oil quenching

Oil quenching is another quenching method for seamless tubes, which is usually used to quickly cool seamless tubes to increase their hardness. Compared to water quenching, oil quenching cools relatively slowly, reducing brittleness while still providing some hardness. As with water quenching, the process conditions for oil quenching, such as quenching temperature, quenching time and tempering conditions, will depend on the specific carbon steel alloy, seamless pipe size and application requirements. Quality control and compliance with relevant standards are important factors in ensuring that the oil quenching process is performed correctly.

3. Salt quenching

In some special cases, pipes can be quenched using salt quenching. Salt quenching typically involves the use of molten salt as the quenching medium, providing higher cooling rates than water or oil while avoiding the brittleness issues that can result from cooling too quickly. One of the advantages of salt quenching is that it provides more uniform cooling, reducing the risk of internal stresses and deformation. However, it is important to note that salt quenching may involve high-temperature molten salt, so appropriate safety measures must be taken.

Specific seamless tube cold treatment processes and parameters may vary depending on the composition of the steel, its use, and the standards or specifications that must be followed. Before implementing any cold treatment process, material properties, welding procedures, and other relevant factors must be carefully analyzed to determine the cold treatment process best suited for the specific application.

Tips: ASTM A106 (ASME SA106) seamless pipes can transport fluids or gases under high temperature and pressure. There are three grades: A, B, and C. The most commonly used ASTM A106 grade B is widely used in oil and natural gas refineries, power plants, petrochemical project factories, and boilers. and ship construction. These pipelines must carry fluids and gases that exhibit higher temperature and pressure levels.