How to avoid downhole pump tripping
In the process of extracting oil from the stratum, mechanical equipment is used to lift the crude oil in the well to the ground, and the sucker rod pump is the main oil extraction equipment.
The sucker rod pump is a special form of reciprocating pump. The power is transmitted from the ground to the downhole through the sucker rod, so that the plunger of the sucker rod pump moves up and down to lift the crude oil in the sucker rod along the tubing to the ground.
There are many types of sucker rod pumps for steam injection thermal exploitation of heavy oil. Tubular sucker rod pumps are prone to scaling in the well during steam injection; rod type sucker rod pumps have the characteristic of not being able to run down the tubing when the pump is lifted. The mechanically locked rod pump is more suitable for the steam injection thermal recovery process of heavy oil. However, this kind of sucker rod pump has a good oil recovery effect in the early stage after steam injection. As the viscosity of crude oil increases in the middle and late stages, the valve ball In the heavy oil, the closing lag, the valve ball in the valve cover prevents the heavy oil from flowing, and the gas lock is prone to occur after steam injection, so that the pump efficiency is getting lower and lower, and the service life of the sucker rod with a small amount of sand particles is low. Tripping occurs in the well, making it inconvenient to fit in and take out the pump.
This design is a multi-functional top mechanical seal rod sucker pump that can prevent tripping and can be connected to a heat insulation pipe for steam injection operations.
This design consists of a pump barrel assembly, a plunger assembly, and a fixed valve assembly. The upper end of the pump barrel assembly is connected to a locking assembly. The locking assembly is equipped with a valve stem extension guide sleeve and a stop valve to support the assembly. The upper and lower connecting threads are tubing threads or insulated tubing threads. The upper end of the valve stem is connected to the sucker rod through a sucker rod joint, and the lower end of the valve stem is connected to the plunger connecting rod of the plunger assembly through a split joint.
The plunger of the assembly has a double plunger and double seal structure. The upper and lower plungers are connected by a plunger connecting rod. The upper joint of the plunger assembly is provided with multiple spiral grooves. The traveling valve of the plunger assembly is a mechanical valve. A spring reset device is provided in the fixed valve assembly.
When producing heavy oil, first lower the support assembly connected with the insulated pipe to the design depth, and then inject steam through the insulated pipe. After the well is stuffed, the multifunctional top mechanical seal rod sucker pump is lowered into the well along with the sucker rod After being in place, the weight of the sucker rod and the sucker pump is locked and sealed by the lock claw of the locking assembly, and then the crude oil is extracted.
When pumping oil, the sucker rod drives the plunger upwards, the traveling valve is closed, the pressure in the lower chamber of the pump barrel is reduced, and the well fluid in the upper part of the plunger assembly is pushed out of the pump barrel, and the lower part of the plunger assembly is vacuumed and fixed. The fixed valve of the valve assembly is opened to suck the well fluid into the pump barrel.
When the sucker rod drives the plunger down, the traveling valve opens in time under the action of the thrust of the sucker rod and the friction between the plunger and the pump barrel, and then pushes the plunger down, the fixed valve of the fixed valve assembly closes, and the well fluid The well hydraulic pressure is pushed to the upper side through the inner hole of the upper and lower plunger and the traveling valve. When the well fluid passes through the spiral groove of the upper joint of the plunger assembly, the well fluid generates a rotating force on it, which causes the plunger to rotate and prevents the column The plug is eccentrically worn and the fixed valve assembly The fixed valve adopts a spring forced reset structure to prevent the fixed valve ball from closing and lagging behind the liquid pressure at the lower part of the plunger to rise. Since the support assembly is equipped with a stop valve to prevent sand from entering the pump barrel and causing sand sticking Plug;
when the viscosity of crude oil increases and steam injection is required, the multifunctional top mechanical seal rod sucker pump can be lifted out or lifted into the tubing along with the sucker rod, and then steam injection, stuffing the well, and then the multifunctional The top mechanical seal rod pump is in place to continue pumping oil. When fracturing, acidizing, test pumping, and ordinary oil production, the support assembly thread can be used to connect the tubing thread. First, the support assembly connecting the tubing is lowered to the design depth, and after fracturing, acidizing, etc.,
the multifunctional top The mechanical seal rod pump is lowered into the well along with the sucker rod for trial pumping. After normal conditions, crude oil can be directly extracted to reduce operations and costs; when the workover operation requires the rod pump to be lifted up The oil rod is used to separate the entire rod-type oil pump from the top support assembly and lift the rod-type oil pump to the ground. If the pump is relatively long and the operation derrick cannot be operated, when the valve stem extension guide sleeve of the support assembly breaks out of the wellhead, an elevator can be placed on the valve stem extension guide sleeve, clamp the valve stem and extend the guide sleeve, rotate the valve stem, and pass The split joint at the lower end of the valve stem removes the valve stem, and then lifts out the rod-type oil pump to complete the entire heavy oil thermal recovery, fracturing, acidification, and oil production integrated operations.
This downhole pump has simple structure and convenient operation. It solves the problems of valve ball closing lagging in heavy oil, valve ball blocking the flow of heavy oil in the valve cover, and easy air lock after steam injection. It effectively improves the efficiency of heavy oil production and extends The injection-production cycle reduces operating costs and greatly increases the service life of the pumps in sand-bearing oil wells.