Characteristics of seamless casing and tubing

Seamless oil casing, oil and gas exploration in the largest amount of a pipe, it relies on male and female buckle buckle which is screwed inside and outside, will a series deep underground steel pipe work. Oil well casing is the lifeline of its quality directly affects the success of drilling operations and the service life of oil and gas wells, related to the oil fields and the manufacturer’s economic benefits.

Seamless Oil casing failure is one of the main problems encountered for each oil field, particularly among the most serious failure of the threaded joint. According to statistics, the oil casing failure occurs in about 64% of accidents threaded connections, the domestic this figure is as high as 86%, securing oil casing threaded joints are the weak link in the oil casing string, therefore, increase the thread connection quality is a key factor in ensuring the quality of the column. Oil casing threaded connections used in the stress distribution directly determines the strength of the connection string. Stress distribution of the parts of the study, not only for manufacturers optimize oil casing thread design, casing and tubing used for predicting the performance provide the basis, but also to guide the proper selection and use of oilfield tubing and casing also has a certain reference value.

The plastic casing and tubing nipple

Seamless oil casing joints is externally threaded male buckle and belt buckle female threaded screw together composed of male and female buckle buckle the contact surface, which is a helical surface, and the oil tube fitting force is more complex. Apart screwed contact pressure generated torque, but also by tension (self-weight of the oil casing), pressure (by the oil, gas or other media caused by) the role of such loads. Oil casing the joint force analysis involves material nonlinearity, geometric nonlinearity and complexity of the contact friction conditions and other nonlinear problems establish a complete and accurate mathematical model, an analytical solution is very difficult.