One-pass Combined Type Cement Retainer

Main Usage

YCGZ - 110
One pass Combined Type Cement Retainer is mainly used for temporary and permanent plugging or secondary cementing of oil, gas and water layers. The cement slurry is squeezed into the annular space through the retainer and needs to be sealed. The cemented well section or the fractures and pores entering the formation are used to achieve the purpose of plugging and repairing leaks.

Structure and Working Principle

Structure:

It consists of a setting mechanism and a retainer.

Working Principle:

Setting seal: When the oil pipe is pressurized to 8-10MPa, the starting pin is cut off, and the two-stage piston pushes the push cylinder downward in turn, and at the same time makes the upper slip, upper cone, rubber tube and lower cone downward, and the driving force reaches At about 15T, after setting is completed, the drop pin is cut off to realize drop. After the hand is dropped, the center pipe is re-pressurized to 30-34Mpa, the ball seat pin cuts off the oil pipe to release the pressure, and the ball seat falls off to the receiving basket, and then the pipe column is pressed down by 5-8T. The oil pipe is pressurized to 10Mpa and is squeezed to check the seal, and it is required to absorb water and squeeze the injection.

Precautions

①This pipe string is not allowed to connect external bypass tools.

②The setting steel balls are not allowed to be preset, and the drilling speed is strictly limited to prevent the pressure caused by the excessive speed of drilling, so that the intermediate coating can be set.

③Scraping and flushing should be performed for the first operation to ensure that the inner wall of the casing is free of scale, sand and particles, so as to prevent setting failure caused by sand and particles blocking the channel of the setting tool. ④After the lower end of the retainer is squeezed, if If the upper end is required to be squeezed, the upper end of the retainer must be squeezed after the cement at the lower end is solidified.

Technical Features

1. The setting and extrusion of the pipe string is completed at one time, which is easy to operate and has a small workload. After the extrusion operation, the lower part can be automatically closed.
2. The open design of the intubation tube and the open design of the cement retainer can effectively prevent the blockage of sand and dirt, and prevent the switch from malfunctioning.