Casing thermal stress protection device

Product description

During the thermal recovery process of heavy oil wells, the temperature difference between before and after steam stimulation is large, which may cause the screen string to be deformed or broken due to thermal extension and compression stress. For such situations, we have designed and developed prestressed completion protection devices.

The device uses the relative movement of the central tube and the outer tube to offset the axial stress of the casing caused by the temperature change, so as to achieve the purpose of protecting the thermal recovery well string.

The prestressed completion protection device is mainly composed of an upper joint, a compensation mechanism, a thermal ring mechanism, and a lower joint. The compensation mechanism is used to offset the compensation distance caused by the expansion and contraction of the pipe string. The thermal ring mechanism has the characteristics of large opening load at low temperature and small opening load at high temperature. The purpose of normal action during the process.

Instructions for use

The position of the prestressed completion protection device is designed according to the length of the well section. In principle, the distance between every two sets of devices does not exceed 80m.
In the process of running the completion string, the prestressed completion protection device can be driven into the designated position according to the design.