Core shaft type sealed oil pipe shoes

Abstract

The invention relates to core shaft type sealed oil pipe shoes. The core shaft type sealed oil pipe shoes are formed by working barrels (1) and core shaft bodies; the core shaft bodies are formed by packing cup pressure caps (2), packing cups (3), core shafts (4), spring pressure caps (5), reset springs (6), core shaft body limiting sleeves (7) and O-ring seals (9); the core shafts (4) are 4-step shoulder shafts; the packing cup pressure caps (2) enable the packing cups (3) to be fastened on the core shafts (4) through screw threads; the spring pressure caps (5) are in threaded connection with the core shafts (4); the core shaft body limiting sleeves (7) sleeve the core shafts (4); the reset springs (6) is arranged in a sleeve manner between the spring pressure caps (5) and the core shaft body limiting sleeves (7); the core shaft bodies are fixed inside the working barrels (1) through shear pins (8); sealing of the core shaft bodies and the working barrels (1) is achieved through the O-ring seals (9). According to the core shaft type sealed oil pipe shoes, the plugging function in a oil pipe can be achieved, meanwhile downhole falling objects are not caused, and the requirements of oil layer test operation of the oil pipe of a water injection well are met.

Description

technical field [0001] The invention relates to a blowout prevention device inside a pipe column used in a pressurized operation process. Background technique [0002] At present, in pipe string operations under pressure, check valves or crappy tail plugs are usually used as internal blowout prevention tools. Check valves and return springs are installed inside the check valves. Due to check valves and Due to the obstruction of return spring and other components, the test instrument cannot pass through the check valve, and the check valve is used as the completion tool. After completion, due to the obstruction of the check valve, the test instrument cannot pass through the tubing to perform oil layer testing operations; the crappy tail plug is made of The mandrel and plugging block are composed. After the completion of the well, the wellhead is pressed and the plugging block is dropped to establish a water injection channel. However, the plugging block needs to fall into the...

AI Technical Summary

Problems solved by technology

[0002] At present, in pipe string operations under pressure, check valves or crappy tail plugs are usually used as internal blowout prevention tools. Check valves and return springs are installed inside the check valves. Due to check valves and Due to the obstruction of return spring and other components, the test instrument cannot pass through the check valve, and the check valve is used as the completion tool. After completion, due to the obstruction of the check valve, the test instrument cannot pass through the tubing to perform oil layer testing operations; the crappy tail plug is made of Composed of working cylinder and plugging block, after the well is completed, the wellhead will be pressed and the plugging block will be dropped to establish a water injection channel, but the blocking block needs to fall into the bottom of the well, resulting in falling objects at the bottom of the well

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