Do you know the processing technology of oil casing?

Oil casing is a large diameter pipe that can be used as a fixed oil and gas well wall or wellbore. Casing is inserted into the wellbore and secured with cement to prevent the wellbore from separating the formation and wellbore, thereby preventing drilling mud from circulating during drilling.

Different types of casing used for oil production: Surface oil casing - protects the well from contamination of shallow water and shallow gases, supports wellhead equipment and maintains other layers of casing. Technical Oil Casing - Separates pressure at different levels to allow proper circulation of drilling fluids and protect production casing. Reservoir Oil Casing - Exports oil and gas from underground storage layers to protect wells and stratify drilling mud. When producing oil sleeves, the outer diameter is usually 114.3 mm to 508 mm.

Within the critical quenching temperature range of 740 to 810°C, AC1=736°C and AC3=810°C of 27MnCrV steel were selected. The heating temperature of sub-temperature quenching is 780°C, and the holding time of quenching heating is 15 minutes. After quenching, the tempering temperature is 630°C, and the holding time of tempering heating is 50 minutes, because sub-temperature quenching is in the α+γ two-phase Zone heating and quenching while maintaining. Partially undissolved ferrite improves toughness while maintaining high strength.

Currently, this process has been applied in steel pipe processing plants. Quality assurance data shows that the yield strength of heat-treated steel pipes is 820-860 mpa, the tensile strength is 910-940 mpa, and the impact toughness is between 65-85j. 100% qualified data shows that 27mncrv steel pipe is already a high-quality, high-grade oil casing. On the other hand, it shows that the sub-temperature quenching process is an excellent method to avoid high-temperature brittleness of steel products.

At the same time, low-temperature quenching has a lower temperature than conventional quenching, which reduces quenching stress, thereby reducing quenching deformation, ensuring the smooth progress of heat treatment production, and providing good raw materials for subsequent wire rod processing.