The present invention relates generally to fluid pumping apparatuses and, more particularly, to guides for valve rods, hollow valve rods, and pull tubes.
Oil well pumping systems are well known in the art. Such systems are used to mechanically remove oil or other fluid from beneath the earth's surface, particularly when the natural pressure in an oil well has diminished. Generally, an oil well pumping system begins with an above-ground pumping unit, which may commonly be referred to as a “pumpjack,” “nodding donkey,” “horsehead pump,” “beam pump,” “sucker rod pump,” and the like. The pumping unit creates a reciprocating (up and down) pumping action that moves the oil (or other substance being pumped) out of the ground and into a flow line, from which the oil is then taken to a storage tank or other such structure.
Below the ground, a shaft is lined with piping known as “tubing.” Into the tubing is inserted a string of sucker rods, which ultimately is indirectly coupled at its north end to the above-ground pumping unit. The string of sucker rods is ultimately indirectly coupled at its south end to a subsurface pump that is located at or near the fluid in the oil well. The subsurface pump has a number of basic components, including a barrel and a plunger. The plunger operates within the barrel, and the barrel, in turn, is positioned within the tubing. It is common for the barrel to include a standing valve and the plunger to include a traveling valve. The north end of the plunger is typically connected to a valve rod, hollow valve rod, or pull tube, which moves up and down to actuate the pump plunger. The valve rod, hollow valve rod, or pull tube passes through a guide positioned at the north end of the barrel, which assists in centering the valve rod, hollow valve rod, or pull tube, and thereby, the plunger. In addition, the guide includes openings through which the oil (or other substance being pumped) may exit the pump barrel and travel into the tubing.
There are a number of problems that may occur during oil pumping operations. Fluid that is pumped from the ground is generally impure, and includes solid impurities such as sand, pebbles, limestone, and other sediment and debris. Certain kinds of pumped fluids, such as heavy crude, tend to contain a relatively large amount of solids. Because of this, several disadvantages exist with prior art guides for valve rods, hollow valve rods, and pull tubes. For example, the orientation of the side openings in such prior art guides permits fluid, and any solid impurities entrained therein, to shoot straight out in the direction of the pump barrel when it is expelled from the guide. This causes damage to the barrel due to the high velocity of the fluid during pumping operations. Further, after the solids have been exhausted from the pump barrel and the pump has temporarily discontinued pumping operations, the solids will naturally begin to settle due to gravity. With prior art guides for valve rods, hollow valve rods, and pull tubes, the solids are able to reenter the pump barrel at this time, via the openings in the guide. This often results in excessive barrel wear upon restarting of the pump. Further, it is possible that with the solids reentering the pump barrel, they may cause sticking of the pump—i.e., seizing the plunger in the barrel.
As another example, solids often cling to valve rods, hollow valve rods, and pull tubes during pumping operations. Typically, with prior art guides for valve rods, hollow valve rods, and pull tubes, this can result in the binding or seizing of the guide to the valve rod, hollow valve rod, or pull tube that is moving up and down actuating the pump plunger. This seizing can cause the pump to stop functioning, by preventing the valve rod, hollow valve rod, or pull tube from being actuated, thereby damaging the sucker rod and guide.
As another example, the north ends of prior art guides for valve rods, hollow valve rods, and pull tubes are frequently subjected to excessive wear and damage by virtue of the sucker rod activity. In this regard, the sucker rod is attached proximate the north end of the valve rod, hollow valve rod, or pull tube (whichever is being employed). The sucker rod sometimes carries side loads when the pump is in a downward stroke. The side loads can impart excessive wear and damage on the side of the guide for the valve rod, hollow valve rod, or pull tube, rendering the guide useless.
A need therefore exists for a guide for a valve rod, hollow valve rod, and pull tube that provides for improved debris removal capability and wear resistance.
The present invention satisfies these needs and provides other, related, advantages.
In accordance with an embodiment of the present invention, a valve rod guide for a pumping apparatus is disclosed. The valve rod guide comprises, in combination: a base region adapted to be coupled to a barrel of a subsurface pump; a body region positioned above the base region, the body region including a plurality of downwardly tapering flutes, wherein each flute of the plurality flutes includes at least one opening to permit a flow of a pumped substance to pass therethrough; a neck region positioned above the body region, wherein an interior diameter of the neck region includes at least one exit port; a head region positioned above the neck region, wherein the head region is adapted to receive at least one sucker rod; and a longitudinal channel passing through the base, body, neck, and head regions wherein the longitudinal channel is adapted to permit a valve rod to pass therethrough.
In accordance with another embodiment of the present invention, a valve rod guide is disclosed. The valve rod guide comprises, in combination: a base region adapted to be coupled to a barrel of a subsurface pump, wherein the base includes an external threaded section; a body region positioned above the base region, the body region including; a plurality of downwardly tapering radial flutes, wherein each flute of the plurality flutes includes at least one opening to permit a flow of a pumped substance to pass therethrough; and a first shoulder and a second shoulder positioned below the first shoulder, the second shoulder adapted to abut a northern end of the barrel of the subsurface pump; wherein each flute of the plurality of flutes extends from the first shoulder to a position above the second shoulder; a neck region positioned above the body region, wherein an interior diameter of the neck region includes at least one exit port; a head region positioned above the neck region, wherein the head region is adapted to receive at least one sucker rod; a substantially ring-shaped insert adapted to fit within an interior diameter of the head region; and a longitudinal channel passing through the base, body, neck, and head regions and adapted to permit a valve rod to pass therethrough.
In accordance with a further embodiment of the present invention, a method for directing fluid through a valve rod guide is disclosed. The method comprises the steps of: providing a valve rod guide for a pumping apparatus comprising, in combination: a base region adapted to be coupled to a barrel of a subsurface pump, wherein the base includes an external threaded section; a body region positioned above the base region, the body region including: a plurality of downwardly tapering radial flutes, wherein each flute of the plurality flutes includes at least one opening to permit a flow of a pumped substance to pass therethrough; and a first shoulder and a second shoulder positioned below the first shoulder, the second shoulder adapted to abut a northern end of the barrel of the subsurface pump; wherein each flute of the plurality of flutes extends from the first shoulder to a position above the second shoulder; a neck region positioned above the body region, wherein an interior diameter of the neck region includes at least one exit port; a head region positioned above the neck region, wherein the head region is adapted to receive at least one sucker rod; a substantially ring-shaped insert adapted to fit within an interior diameter of the head region; and a longitudinal channel passing through the base, body, neck, and head regions and adapted to permit a valve rod to pass therethrough; pumping the fluid northward through the valve rod guide by causing the fluid to enter the base region, to then enter the body region, to then enter the neck region, to then exit the valve rod guide, wherein the fluid has solid impurities entrained therein.
Referring first to
Turning first to the base region 22, as shown in this embodiment, and as seen in
The body region 20, as shown in this embodiment, includes a first shoulder 28, a second shoulder 30, and a plurality of flutes 34. The first shoulder 28 may be rounded, as shown in this embodiment. The second shoulder 30, as shown in this embodiment, may be substantially squared-off. When the valve rod guide 10 is coupled to the barrel of a subsurface pump or the like (not shown), the second shoulder 30 may be positioned to abut the northern end of the barrel. The second shoulder 30 may include ridge 32. As shown in this embodiment, ridge 32 may be angled downwardly (southwardly).
Referring to the flutes 34, in this embodiment, three flutes 34 are included in the valve rod guide 10, as best seen in
The downward (southward) tapering of the flutes 34 proximate position 38, as discussed above, may provide one or more advantages. For example, this design assists in preventing solids that have been exhausted from the pump barrel through the flutes 34 from reentering the pump barrel. This is a problem with standard prior art valve rod guides, as solids often reenter the pump barrel by way of the valve rod guide. This occurs after pumping operations have stopped and the solids have begun to settle due to gravity. When solids settle back into the pump barrel and the pump is restarted, excessive barrel wear can result, as well as sticking the pump—i.e., seizing the plunger in the barrel. Accordingly, by preventing the reentry of solids into the pump barrel, the operating life of the pump and its components may be extended.
The neck region 18 includes a lower portion 40, an upper portion 42, and a plurality of exit ports 44. In this embodiment, the exit ports 44 are spaced equidistant from each other, but could be spaced apart in other configurations. In one embodiment, for example, three exit ports 44 may be employed. However, it may be desired to configure a valve rod guide 10 having more than three or fewer than two exit ports 44. In one embodiment, the exit ports 44 may be oriented on an upward (northward) angle. (For example, it may be desired for the exit ports 44 to be oriented on an upward angle corresponding to the upward angle orientation of the flutes 34, as mentioned above.) In this way, the exit ports 44 will direct the flow of solids and fluids northward as they are exhausted through the exit ports 44.
Turning now to
The design of the spiral radial flutes 50 and their extension from the lower groove 46 to the upper groove 48, as discussed in the preceding paragraph, may provide one or more advantages. For example, during pumping operations, this design facilitates the wiping of solids from the valve rod as the valve rod travels through the channel 24 of the valve rod guide 10. This allows for the accumulation of such solids into a common area. In this regard, on a downstroke, the solids are wiped from the valve rod and dragged into the spiral radial grooves 50, to be moved downwardly through the spiral radial grooves 50 and to accumulate in the lower groove 46. On an upstroke, the solids are wiped from the valve rod and dragged into the spiral radial grooves 50, to be moved upwardly through the spiral radial grooves 50 and then expelled through the exit ports 44 as a result of friction between the solids and the valve rod that drags the solids toward the exit ports 44. Once the solids have arrived at the exit ports 44, they are prevented from traveling further upward (northward) within the channel 24 of the valve rod guide 10, due to a tight fitting at the top of the valve rod guide 10, as further discussed below. The solids thus accumulate in the area of the upper groove 48, and are then forced out of the exit ports 44 by way of the energy produced by the travel of the valve rod. This keeps the valve rod guide 10 from binding or seizing to the valve rod. Such seizing would cause the pump to stop functioning by preventing the valve rod from being actuated, and could cause damage to the sucker rod and valve rod guide as a result.
While this embodiment illustrates exit ports 44 positioned proximate the upper groove 48, it may be desired to also include another set of exit ports (“exit ports 45”), as shown in
Referring again to
Referring now to
Referring now to
While the embodiment of the valve rod guide 100 shown in
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.
This non-provisional application claims priority from provisional application No. 61/110,050, filed on Oct. 31, 2008, in the name of the inventor of this non-provisional application.
Number | Date | Country | |
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61110050 | Oct 2008 | US |