At the oilfield well repair operation site, overflow or intermittent spraying is prone to occur during the lifting and lowering of the pumping rod, which not only affects the operation construction and pollutes the environment, but also poses significant safety hazards. The self sealing device of the pumping rod adopts a hydraulic rubber core to seal the coupling of the pumping rod and the oil pipe annulus to achieve well sealing, solving the technical problem of controlling overflow or intermittent spraying during the process of lifting and lowering the pumping rod. This device fills the gap of no well control equipment for lifting and lowering pumping rods.
Structure and working principle
The device consists of a shell, a hydraulic rubber core, a pressure cover, a sealing ring, etc. The lower shell cylinder is equipped with a hydraulic rubber core, and the hydraulic annular rubber core is cylindrical. The longitudinal section is X-shaped, which facilitates compression deformation under the action of hydraulic oil.
Working principle and installation usage:
Installation: First, connect the lower thread of the self sealing device of the pumping rod directly to the three-way thread at the wellbore, and then connect the device to the manual hydraulic oil pump with a high-pressure hydraulic hose.
Installation and use:
Before use, the oil cylinder should be filled with hydraulic oil, and a hydraulic sealing pressure test (with a rubber core built-in pumping rod coupling) of 14Mpa should be conducted in the pressure testing workshop. A pressure drop of less than 0.7Mpa within 5 minutes is considered qualified, and only after passing the test can the well be put into operation.
When there is overflow or low-pressure spraying, the coupling body of the pumping rod should be placed in the middle position of the rubber core as soon as possible, and the handle of the hydraulic oil pump should be shaken to compress the rubber core of the hydraulic oil and lock the coupling body of the pumping rod to complete the annular sealing.
When there is a high pressure or blowout in a well with large gas volume, the three-way gate should be opened in a timely manner to prevent blowout after completing the annular sealing, to ensure that the sealing pressure does not exceed the maximum pressure value of the self sealing device.
After completing the high-pressure sealing, the pump head gate should be rotated counterclockwise to the end for pressure relief. The hydraulic oil in the oil chamber should return to the oil tank, and the hydraulic self sealing rubber core should return to its free state.
During normal operation, there is no need to start the hydraulic pump, only fill the oil chamber in this device with hydraulic oil, that is, the hydraulic self sealing rubber core is in a free state, and the oil pump can be started and stopped normally.
Main technical parameters
1. Maximum working pressure for sealing: 14Mpa
2. Maximum load capacity: 30 tons
3. Hydraulic control pressure: 0-40Mpa
4. Minimum diameter of steel parts: 60mm
5. Maximum size: 452 * 140mm
6. Connection method: 2-7/8 "TBG
7. Operating temperature: -20-+50 ℃
8. Media used: oil, gas, water, mud
main features
1. This device is safe to install and operate, and can effectively eliminate well control safety risks during the process of lifting and lowering pumping rods.
2. By adjusting the appropriate pressure on the rubber core, the coupling annulus of all diameter pumping rods can be sealed.
3. Equipped with a manual hydraulic pump, it can be remotely controlled from 5-10 meters away from the wellhead. In case of overflow or blowout, it can quickly seal the annular space between the pumping rod and the oil pipe to prevent pollution.
4. This device is suitable for the construction of oil field well repair operations, such as overflow or intermittent well spraying, pressurized well washing and degassing during the process of lifting and lowering pumping rods
