In addition to being used for oil extraction, the emergence of oil casing can also be used as a pipeline for transporting raw materials. To enhance the quality of oil casing, every link in the production process is particularly important, especially the temperature control during the period, which must be strictly followed. Regulations mastery. Normally, petroleum casing adopts a sub-temperature quenching method instead of the ordinary quenching method, because the ordinary quenching method will leave a large amount of residual stress inside the workpiece, thereby expanding the brittleness and making subsequent processing less convenient. The sub-temperature quenching is to prevent the excessive brittleness of the oil casing from affecting the subsequent process. The main operation method is to first select the heating temperature for sub-temperature quenching, usually between 740-810°C, and the heating time is generally about 15 minutes. After quenching, tempering is performed. The heating time for tempering is fifty minutes, and the temperature should be 630°C. Of course, each type of steel has its heating temperature and time during heat treatment. As long as it can improve the performance of the workpiece, then heat treatment The purpose is achieved.

Heat treatment is the most important process in the processing of petroleum casing. Whether the performance and quality of the finished product can meet the standards largely depends on the results of heat treatment. Therefore, each manufacturer has very strict requirements for the heat treatment process and dare not neglect it. Sometimes low-temperature quenching can be used for quenching. Low-temperature quenching can effectively remove the residual stress of the oil casing. It not only reduces the degree of deformation of the workpiece after quenching but also processes the oil casing into raw materials more suitable for later processes. Therefore, the current achievements of oil casing are inseparable from heat treatment. Since the heat treatment process has been introduced, whether it is the impact toughness, anti-destruction performance, or tensile strength of oil casing, there has been a great improvement. improve.