High Gas Cut Well Downhole Pump
- In oil wells with high gas cut, the oil liquid has poor fullness. So if we adopt conventional sucker rod pumps for oil recovery, normally we will get a very low pump efficiency. Meanwhile, gas locking may happen frequently, which will bring a lot of trouble to oil recovery and make us lose countless time and money for repairing the downhole pumps.
- What is more serious? Operation with conventional sucker rod pump in high gas cut wells will result in liquid impact, which would accelerate the damage of tubing, sucker rod strings, pump valves, valve cages, and other downhole equipment.
- We, Sanjack Petro, have specially designed sucker rod pumps for high gas cut wells to avoid these problems: Gas locking prevention oil well pump, long plunger anti-gas & anti-sand downhole pump, forcing valved open type insert pump, double-plunger valve type sucker rod pump, etc.
High Gas Cut Well Downhole Pump Manufacturers and Suppliers
Avoid Gas Locking
The traveling valve is a spherical valve for forced opening and closing.
Avoid liquid Impact
The unique design of the high gas cut well downhole pump can effectively prevent liquid impact.
The patent anti sand and anti burying standing valve can prevent valve seat from being punctured.
The plunger can rotate freely to prevent sand stuck and partial wear.
- Forced opening and closing.
- Avoid sand stuck and partial wear.
- With anti-gas device.
- Light oil well with high gas cut.
- Sand content of oil well≤2%.
- high gas-oil ratio.
- Sand content of oil well≤2%.
- high gas-oil ratio.
Gas locking: After frequent compression and expansion of the gas in the sucker rod pump, the suction valve often cannot be opened normally. So that the crude oil cannot be pumped out. This phenomenon is called “gas locking”.
Liquid impact: During the upstroke, if the pump is not completely filled with well liquid, a low-pressure air cap will be formed on the top of the pump chamber between the floating valve cage and the fixed valve cage. During the subsequent downstroke, the gloating valve cage will keep closed until being hit by the well liquid surface. This phenomenon is called “liquid impact” and it will cause severe impact load on the entire artificial lifting system.
Buying Guide of Special Pumps for High Gas Cut Wells
The Hazard of High Gas Cut In Oil Wells
In oil wells with high gas cut, the oil liquid has poor fullness.
So if we adopt conventional sucker rod pumps for oil recovery, normally we will get a very low pump efficiency.
Meanwhile, gas locking may happen frequently, which will bring a lot of trouble to oil recovery and make us lose countless time and money for repairing the pumps.
What is more serious?
Operation with conventional pumps in high gas cut wells will result in “liquid impact”, which would accelerate the damage of tubing, sucker rod strings, pump valves, valve cages, and other downhole equipment.
The article will describe in detail the use and selection of oil well pumps in high gas cut wells.
Artificial Lift Technology
Artificial lift technology uses some means to increase the flow of liquids, for example, crude oil or water with some amount of gas included to the surface of production well.
The following mostly achieves this.
1.A mechanical device inside the well
2.Decreasing the weight of the liquid or gas mixture via high-pressure gas
3.Improving the lift efficiency of the well through velocity string
An artificial lift system is needed in wells will less pressure in the reservoir to boost the liquid to the surface.
However, these systems are sometimes used in flowing wells to increase the naturally occurring flow rate.
More than 55 percent of producing oil wells require some assisted technology to create recoverable oil.
Much artificial lift or pumping technologies are applied, including plunger lift, beam/sucker rod pumps, gas lift, progressive cavity pumps, or electric submersible pumps.
This artificial lift method is used basically in gas wells to remove relatively small volumes of liquid.
Functionally, a plunger-lift system provides a mechanical interface between the produced fluids and gas by using the well’s energy for lift; liquids are pushed to the surface by the movement of a free traveling piston or plunger that travels from the bottom of the well to the surface.
The mechanical interface removes liquid fallback, which, however, boosts the well’s lifting efficiency.
Plunger travel is usually provided by formation gas stored in the casing annulus during a well shut-in period.
As the well is opened and the tubing pressure reduces, the stored casing gas moves around the tubing end and pushes the plunger to the surface.
This irregular operation is separated several times per day.
b.Sucker Rod Pumps
Sucker rod pumps, rod pumps, and beam pumps refer to an artificial lift system that uses a surface power source to drive a downhole pump assembly.
A beam and crank assembly at the surface creates reciprocating motion, converted to vertical motion in a sucker-rod string that connects to the downhole pump assembly.
The pump contains a plunger and valve assembly to impact vertical fluid movement.
Due to its long history, sucker rod pumping is a prevalent means of artificial lift.
Gas-lift systems that inject gas into the crude are sometimes used in conjunction with surface operating reciprocating pumps or horizontal centrifugal pumps.
However, these systems become far less efficient in deeper, deviated wells.
Gas-lift systems always increase the degree of component flow construction caused by scaling and paraffin crystal accumulation.
Moreover, these techniques supply of gas to be stored at the surface.
The gas that is separated and vented is not easily retained for re-injection, and gas that is re-injected rapidly becomes contaminated with oxygen, carbon monoxide, and hydrogen sulfide that can corrode production string components
d.Progressive Cavity Pumps
The progressive cavity pump is a closely related technology to the electrical submersible pumps. The progressive cavity pump system consists of a helical bore that rotates inside a similar spiral cavity.
The bore’s rotation creates cavities with negative pressure to open and close, forcing fluid up through the pump body.
The progressive cavity pump offers proven performance in extracting crude oil at high viscosity.
However, progressive cavity pumps are vulnerable to damage from abrasive materials and are limited to good depths of approximately 5000 ft. progressive cavity pumps do not perform well in deviated wells.
Forced Opening Valve Type Insert Pump
Insert pump is a pump that is inserted in the tubing and runs like an assembled unit along with the sucker rods.
This kind of pumping is anchored in a mechanical or cup-type seating nipple that runs as part of the tubing string.
The pump is always removed from the tubing by pulling the sucker rod string. The pump should be smaller than the tubing pump and hence should consist of a less capacity of the particular tubing size.
The insert pump and tubing pump can be easily serviced by pulling the sucker rod string.
These pumps are made with the top or bottom holds downs.
They can be found with mechanical hold down or three cup seating assembly.
They contain precision barrels of around forty inches and available in horned and hardened, Nicarb and Brass.
They apply primarily to the wells with great depth.
Types of forced opening valve type Insert Pumps
Stationary Barrel, Bottom Anchor
In a stationary barrel, the bottom anchor pump can be used in shallow to very deep wells and is typically the most accepted insert pump option.
Due to its design, the traveling valve has the option to be smaller than the standing valve.
The fluid column inside the tubing supports the pump barrel continuously; with differential pressure reduction, the pump has improved efficiency and a longer life pump.
One standard limitation of this insert pump style is sand tends to settle around the barrel, and the scale can make it challenging to pull the pump.
However, this issue can be resolved by stripping the well where the workers simultaneously pull the rods and tubing.
Stationary Barrel, Top Anchor
This particular pump has the hold down located at the top of the pump. It is designed so the pump hangs below both the tubing perforations and the seating nipple.
This type of arrangement is excellent with sandy, shallow wells with a depth of fewer than 5,000 feet due to the fluid’s whirling motion created during operations in the area at the pump’s top.
The pressure inside the barrel pump is far higher than the casing pressure located outside of it.
Allowing the barrel pump’s inside the ability to resist the pressure created by the fluid column, but this does limit the depth at which the downhole pump can operate safely; due to gas pounding.
Traveling Barrel, Bottom Anchor
This barrel option will operate in corrosive, normal, and sandy wells with positive results.
During each stroke, the barrel rushes liquid around the pump’s bottom, causing sand to possibility stick around the pump on the inside.
If the design uses an open-style valve cage, it will provide less restriction during the pumping of heavy crude oils.
Simultaneously, the traveling barrel option offers better defense against busting, especially for designs using a heavy barrel.
This type of pump’s main limitation is it is more likely to gas lock than stationary barrel options.
The traveling barrels.
Is more likely to experience wear during operations because the traveling barrel is larger than the standing valve.
However, this also makes it less productive in situations with crooked holes, and therefore, the pump may require a guide.
Gas locking prevention oil well pump
Gas locking has been a problem with the ball and seat sucker rod pump ever since its interception in the oil industry. A gas lock occurs when contrary to a sucker rod pump’s normal functioning due to a gas influx from the standing valve.
The pressure produced by the fluid below the traveling valve in the closed chambers does not overcome the weight of the liquid column lying above the traveling valve in the pump barrel. This fails to lift off the seat.
However, this review brings forth a sucker rod pump design consisting of a solenoid actuated hydraulic valve in the traveling plunger seat to address this failure.
The traveling section is a valve in the plunger seat connected with a solenoid actuator at the surface for executing an open or close mode.
The electric supply for the valve of the valve is provided through a wire conduit that is found in the polish connected to a control system installed at the surface.
A sensor is placed to sense the beginning of each up and downstroke of the plunger.
At the beginning of each downstroke, the solenoid is set to provide power for the valve to open.
This external drive for the valve opening compensates for the negative variation in magnitude of the fluid pressure differential between the traveling and standing sections, thus enabling fluid intake into the pump barrel.
The sensor detects the end of the stroke; the hydraulic valve piston is seated back for the valve to close. This allows the lifting of the fluid in the pump barrel during the upstroke. This design aims at latency-free synchronization of the valve opening and closing with pump reciprocator under circumstances of gas interference.
From this principle, this mechanism of voluntarily opening the valve during the downward motion would prevent the gas lock problem.
This would also increase the efficiency by eliminating non producing compression strokes, which are also causing a sudden pump break down.
Long plunger anti-gas lock and anti-sand downhole pump
A good pump has a standing valve seat as well as a standing valve mounted in the lower end of the plunger.
The traveling valve has a stem extending downward from the head through a hole in the traveling magnet.
The magnets’ polarities are configured to interact and cause the traveling valve to lift relative to the traveling seat to an open position as the plunger nears a bottom of a stroke.
Method and apparatus are overcoming gas locking reciprocating downhole pumps. On the downstroke of a plunger in a barrel, gassy fluid is compressed in the pump chamber between standing and traveling valves.
The download plunger movement drags a sleeve of a mandrel that opens the valve to a staging chamber that is located at a downhole end of the traveling valve for receiving at least a portion of the compressed and gassy fluid therein.
During the upstroke, the chamber valve is dragged closed for sealable. It is retaining the compressed gassy fluid therein while drawing an additional increase of fluid through the standing valve into the pump chamber.
When the downstroke process is continued, and upstroke cycles increase the pressure of the compressed gassy fluid in the pump chamber until it exceeds the hydrostatic head above the travelling for the resumption of regular fluid pumping.
How to choose the right special pumps for high gas cut wells
A pump is a mechanical device that transports media by transforming the energy supplied by a motor into hydraulic energy.
The first and criterion for choosing a pump is the type of media concerned.
Moreover, the technical characteristics of the media must be taken into account because they will determine the choice of the pump.
In order to properly dimension the machine and calculate the operating point of the pump, it is crucial to know the parameters of the network such as sanction head, flow rate, discharge head etc.
However, this guide will give you an overview of the main types of pumps and the typical situations in which they are used.
This guide will give you an overview of the main types of pumps and the typical situations in which they are used.
For you to choose a pump that meets your needs, you must determine its characteristics according to its use.
First and foremost, you must determine what media will be transferred to avoid corrosion phenomena and, therefore, premature wear of your pump.
Therefore, it is vital to be aware of the chemical composition of the media to be pumped, its viscosity, and the possible presence of solid components.
Detailed knowledge of the treated fluid’s physical properties will allow you to choose the best technology for your application and the construction materials compatible with the pumped media.
There are several chemical compatibility tables to consult before choosing the casing of your pump.
Then, you should also check the characteristics related to transporting the media, in particular:
The flow you require: generally, it is measured in m3/h (cubic meters per hour) or GPM (gallons per minute); the flow necessarily influences the size and dimensions of your pump;
The suction head, which is the height between the inlet of the suction pipe and the pump: as a general rule, the suction head must not exceed 10 meters. Beyond this, it is necessary to consider using a submersible pump.
The discharge head or height between the pump and the discharge pipe outlet).
The length of the discharge circuit
Head losses linked to obstacles on the pumping circuit, e.g., valves, bends, etc.
Whether there is a discharge tank or not could change the head.
The temperature thus depends on the choice of the pump casing.
These different values allow you to calculate the Net Positive Suction Head available of the setup.
This will enable you to choose the best pump and avoid any risk of cavitation.
You will also have to control efficiency.