High-Tech of Oil Casing Pipe: Heat Treatment Technology

After adopting this heat treatment method, the oil casing pipe can effectively improve the impact toughness, tensile strength and anti-destructive performance of the oil casing, and ensure the good value in use. Oil casing is a common pipe for drilling oil and natural gas, and it needs to have good performance in use. The oil casing is controlled by different temperatures in different temperature zones, and the heating needs to be produced according to a certain temperature. K55 oil casing material steel AC1 = 736°C,AC3=810°C, tempering after quenching selects temperature 630°C, tempering heating time 50min, heating temperature during sub-temperature quenching is selected between 740-810°C. The sub-temperature quenching selects the heating temperature of 780 ° C, and the holding time of the quenching heating is 15 min. Since the sub-temperature quenching is heated in the α + γ two-phase region, the local undissolved ferrite is stored for quenching. While adhering to higher strength, the toughness has also improved.

The heat treatment of the oil casing pipe needs to be strictly implemented to ensure the production of the oil casing has good product quality and performance, exhibits good use value and performance in use, adheres to high strength and toughness, and performs heat treatment in different ways.

At the same time, the low temperature quenching is lower than the conventional temperature, which reduces the quenching stress, thereby reducing the quenching deformation, thus ensuring the smooth operation of the oil casing heat treatment production, and providing a good raw material for the subsequent wire processing .

At present, the process has been applied in pipe processing plants of different steel pipes, and the quality assurance data shows that the tensile strength of the oil casing after heat treatment is Rm910-940MPa,yield strength Rt0.6820-860MPa, 100% proof of damage resistance, impact toughness Akv65-85J data indicates that K55 oil casing is relatively good quality high-grade steel casings, on the other hand, also show that the sub-temperature quenching process is an effective method to avoid high-temperature brittleness in the production of steel products.