Oil-specific seamless tube is mainly used for oil and gas wells drilling and oil, транспортировка газа. It includes oil drilling pipe, oil casing, pumping pipe. The oil drilling pipe is mainly used to connect drill collar and drill bit and transmit drilling power. Oil casing is mainly used in the drilling process and completion of the wellbore after the support to ensure that the drilling process and the completion of the entire well after the completion of the normal operation. The oil pumping pipe mainly sends oil and gas at the bottom of oil well to the ground.
Oil casing is the lifeblood of oil wells. Due to the different geological conditions, the stress state of the underground is complex, and the combined effect of tension, сжатие, bending and torsional stresses acts on the pipe body, which puts forward high requirements for the quality of casing itself. Once the casing itself for some reason and damage, may lead to the whole production of wells, or even scrapped.
According to the strength of the steel casing can be divided into different steel grades, а именно J55, К55, N80, L80, С90, Т95, Р110, Q125, V150 and so on. Well conditions, well depth, the use of steel grades are also different. Corrosion in the environment also requires the casing itself has anti-corrosion properties. In places where geological conditions are complex, casing is required to have anti-collapse properties.