US1794427A - Apparatus for pumping wells - Google Patents

Description

l Patented Mar. 3, 1931 UNITED STATES PATENT OFFICE ARTHUR F. WHITE, F FULLERTON, CALIFORNIA, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO JORDAN & TAYLOR," INC., 0F LOS ANGELES, CALIFORNIA, A. CORPORATION OF- CALIFORNIA ArPARA'rUs ron `1=UMPING WELLS Application led August 6, 1928. Serial No. 297,665.

My invention relates to a gas-lift pumping mechanism of novel form, and it is a primary obj ect of this invention to provide a novel apparatus for pumping a well.

In 011e method of pumping wells it is customary to extend a pipe downward to a point below the surface of the liquid in the well and to introduce a compressed gas either into the lower end of this pipe or into the space above l0, the Surface of the liquid, this gas forcing the well liquid in the pipeupward Xto the surface of the ground.` The pressure of this coml pressed gas is quite high, and with such a pumping mechanism this pressure is trans- 15, mitted to the liquid-bearing strata of the well, thus tending to impede lthe inflow of more liquid. In order to allow more liquid to enter the well it is necessary to release the pressure on the liquid-bearing strata, thus neces- Isitating a large waste of compressed gas when `the Yspace above the liquid in the well is vented. y

It is an object of my invention to provide'a gas-lift pumping mechanism wherein the pressure of the compressed gas cannot reach the liquid-bearing strata. f i

A further object'of my invention is to "provide a gas-lift pumping apparatus in which the differential pressure between the liquidbearing strata and the interior of a well-casing may be regulated.

I have found that a very eicient pumping action takes place when a compressed gas is' intermittently suppliedto a chamber at least partially submerged in the well liquid, this gas pressure closing the liquid-intake valves of the chamber and forcing the liquid entrapped in the chamber upward through a delivery pipe whicl extends into the cham- 40 ber. A check valve prevents any return flow of liquid through the delivery pipe. Furthermore, I have found it advantageous'to vent the chamber to the exterior of the pumping mechanism when the gas has been shut oill and a new supply of liquid is entering the chamber.

It is an object of my invention to provide a chamber situated at least partiallybelow the liquid level of a well and adapted to e11- trap a body of liquid therein, this liquid being displaced by a compressed gas supplied to the chamber from the surface of the ground.

A further object of my invention is'to position a gas-intake valve situated adjacent such ay chamber,and controllable' from the surface of the ground to supply a compressed gas to the chamber.

Still a further object of my invention is to'provide a venty for such a chamber, which is closed when the gas-intake valve is open, and compressed gas is entering the chamber, but open when a new supply of liquid is entering the chamber. l

Still another object of my invention is to provide a noveln arrangement of tubing for supporting a gas-lift pumping mechanism and for supplying compressed gasthereto and conducting thel pumped liquid therefrom. y

Referring to the drawings, in which I illustrate a preferred embodiment of my invention:

Fig. 1 is a vertical sectional view illustrating the utility of my invention and showing the gas-intake valve thereof in closed position.

Fig. 2 is a sectional view taken' on the line 2 2 of Fig. 1.

Fig. 3 is a sectional'view taken on the line 3-3 of Fig. 2 and illustrating the valve in another position.

F Fig. 4 is a view taken on the line 4-4 of `Illig. 5 is a view taken on the line 5--5 of Fig. 3.

Referring particularly to Fig. .1, I illustrate a well 10 in which a well-casing 11 has been set, this well-casing preferably extending downward to the liquid-bearing strata of the well indicated by the numeral 12, and being perforated adjacent these strata. The upper end of the casing 11 is closed by a head 13, and the pressure inside the casing is regulated by a valve 14 placed in a pipe 15 communicating with the interior. of the casing.

This lpressure may be registered on a 4 the liquid levelnormally present in the well, this liquid level being indicated by the line A-A of Fig. 1. Threaded to the lower end of this primary tubing is a chamber structure 22 having a head member 23 in which a bore 24 is formed in a manner to lcommunicate with the interior of the tubing 20. The lower end of the bore provides a seat25 in a groove of whichanA annular packer 26 is retained in a manner best shown in Fig. 3.

The conical face of a plug member 28 is adapted to engage the annular packer 26, this packer being adapted to maintain a fluidtight engagement between the plug member 28 and the head member 23. u

A secondary tubing 30 is threadedly received by the upper end of the plug member 28 and at least partially supported thereby, this tubing extending upward through thel primary tubing and through a head 31 thereon, being capped at its upper end by a head 32 communicating with an outlet pipe 33. Compressed gas is adapted to be intermittently supplied to an annular intake space 35 'between the primary and secondary tubing through a pipe 36 communicatingwith the head 31. This intermittent flow of gas is regulated by any suitable mechanically or electrically operated valve mechanism 37 of such a type that the time interval of gas flow through the annular space 35 may be readily varied, as well as the time between successive lgas iiows therethrough.

The lower end of the head member 23 is threaded to receive a shell 40, which is closed at its bottom and forms a part of the chamber structure 22, this shell and the head member 23 cooperating to form a pumping charmber 41 which may be relatively long and eX- tend through a considerable proportion of the distance between the liquid level A-A and the lower portion of the well 10 if so desired. I prefer to position the chamber 41 so that it lies almost completely below the surface A-A, but my invention will operate as long as the chamber 41 is at least partially submerged in the well liquid.

This chamber is adapted to receive well liquid through liquid-intake valves 42 situated near the lower end of the chanber. I have illustrated these valves as being of the flapper type but it should be understood that I am not limited thereto. Any form of valve', which will admit liquid into the chamber 41 and prevent an outward flow, will serve the purpose.

The interior of the secondary tubing 30 Y communicates with the chamber 41 through a bore 43 formed centrally through the plug member 28, and an opening 44 formed through the head member 23. The opening 44 is axially aligned with the'vbore 43the lower end thereof being threaded to receive a delivery tube 45, which extends downward through the chamber 41 to a position near the lower end thereof. The lower end of the delivery tube 45 carries a seat 46 in which a ball 47 is adapted to normally rest, this ball being displaced upward in a cage 48 when liquid is rising in the delivery tube 45. The seat 46 and ball 47 cooperate to form a check valve to prevent any iow of liquid from the delivery tube 45 into the chamber 41.

As the well liquid is entering the chamber 41, it is desirable to vent the upper end of this chamber to the exterior of the head member 23. This I accomplish by means of vent openings 56, best shown in Fig. 3. These openings preferably communicate with the space above the liquid level A-A, but this arrangement is not necessary to my invention,

inasmuch as any gas passing through the vent openings 50 will rise in the well fluid surrounding the head member 23 should the level A-A be above the openings 50.

An intake passage 53 is formed in the head member 23 and communicates at the one end with the annular space 35, the other end of this passage communicating with a valve chamber 54, there being a conical seat 55' formed at the point where the passage 53 ,opens on the valve chamber 54. The lower end of the valve chamber communicates with the pumping chamber 41.

Adaptedvto slide in the passage 53 is a stem 56 of a gas-inlet valve 57, which forms a fluid tight fit therein until this valve is lowered a sufficient distance so that the bottom of a notch 59 enters the valve chamber 54, at which time compressed gas may iow from the annular space 35 through the passage 53 and into the pumping chamber 41 through the Valve chamber 54. Ahead 60 is formed on the gas-intake valve 57 and is journalled in the valve chamber 54, this head having passages 61 allowing the compressed gas to pass. VThe upper end'of the head 60 is provided with a conical face 62, which is adapted to engage the seat 55, thus determining the yuppermost position of the gas inlet valve 57.

to allovvthe vcompressed gas to enter the pumping chamber 41. The head 60 and the plunger 65 are separated by a spring 67, this A spring being of such a length that the maximum separation of the head and the plunger takes place when the mechanism is in a position indicated in Fig. 3.

The lower end of the plunger 65 bears against a ball 68, held in a pocket 69 of a valve member 70, which is formed of a shape best shown in Figs. 1, 2, and 3. This valve member has an opening 72 through which the delivery tube 45 passes, and pins 73 journal this valve member so that it may be pivoted about an axis B-B passing through the axis of the delivery tube 45, so that the valve lill ' against the stem 56 of the 'member may be moved from a position shown A-A and the liquid intake valves 42.

in Fig. 1 into a position shown in Fig. 3.

Such a movement takes place when the valve 37 allows the compressed gas to enter the annular space 35 and build up a pressure as-intake' valve 57. This pressure is resisted by a spring 75 positioned in a bore 76 extending upward into the head member 23, this spring-bearing against a piston 77 which in turn is operatively connected to the valve member by a ball 78. As will be apparent in the drawings, the bore 76 is on the opposite side of the head member 23 from the valve chamber 54, so that as the gas pressure on the stem 56 builds up, the spring is compressed, due

'to the fact that this spring is more easily compressed than Ithe spring 67. The valve member 70 thus moves into a position indicated in Fig; 3, at which time the lower end of each vent opening`50 is closed by a ball 80 held in a cup 81 of the valve member 70. An opening 82 communicates withthe cup 81 and prevents any excess ordeiciency of pressure in thiscup. The effective areas of the piston 77 and plunger 65 are preferably equal so that any pressure which builds up in the chamber 41 acts equally on these members.l The valve member 70, together with the parts mechanically connected thereto and adapted to control the passage of gas to and from the chamber 41, forms a pressure-operated valve operable from the surface'ot the ground.

When the mechanism is in this position, the

bottomv of the notch 59 has not quite reached the valve chamber 54, so that no gas escapes from the lannular space 35 into the pumping chamber 41. *When the gas in this annular passage becomes great enough to overcome the action `ofthe spring 67, the gas intake valve 57 lowers against the action of the spring 67 and compressed gas enters the upper end ot the pumping chamber 41. Any Well liquid in this chamber is entrapped therein due to the valves -42 preventing anyV of the liquid from escaping into the casing 11. The gas pressure thus built up in the upper end oi the chamber '41 forces the liquid downward in this chamber,this liquid rising in a discharge passage 85, formed by the delivery tube 45, the opening 44 and bore 43, and the secondary tubing 30 yto' the surface of the ground and being discharged through the outlet 33. Y

When the valve mechanism 37 operates to shut off the supply et compressed'gas, the/- spring 67 expands, thus-bringing the bottom ot' 'the notch 59 abovethe valve chamber. The spring'l 75 now operates to throw the valve member into its position shown in Fig. l, thus uncovering the vent openings 50 and allowing the upper end of the chamber 41 to be vented therethrough so that a new supply of oil may enter lthe pumping chamber 41 due to the pressure head between the surface rThe liquid rises in the chamber 41 until it reaches a level substantially the same as the liquid level A-A of thewell, or until the .I

Ichamber is completely filled in the event that this chamber is completely submerged.,

During this rise of liquid the gas thereabove is forced' through the vent openings 50. It should be understood that the spring 75 acts to liold the valve mechanism in the position shown in F ig. 1 until the timing mechanism 37 acts to again supply a compressed gas to the annular space between the primary and secondary tubing. When the pressure .difference between the annular space 35 and the interior of the chamber 41 again reaches the.

predetermined value the series of operations above outlined is repeated.

rlhere are several possible methods of operating my invention by regulating the timing mechanism 37. I prefer, however, to so adjust `this mechanism that the chamber 4l will be substantially completely filled with well liquid before the compressed gas actuates the valve mechanism. Furthermore, I prefer to lower the liquid level in thechamber 41 to a point below the seat 46,- so that a column 'of gas enters the discharge passage 85. In the latter event, it is necessary to attach the outlet pipe 33 to a suitable separator for separating the gas and liquid. Such separators are well-known in the art and do not form a part of this invention.

l have found such a method of procedure p particularly applicable to the pumping of an oil well. All oil, as it is taken from the ground, contains therein certain entrained gases which are liberated when the pressure on the oil is reduced. As a slug of oil passes upward through the discharge passage 85,

lthe pressure thereon becomes less as this oil nears the surface of the ground. 'llhis slug of oil thus becomes more buoyant during the upper portion of its travel, and by a proper regulating of the' timing mechanism 37 it isv lli) trapped in the chamber 41 is completely expelled from the well, although this mode of operation gives poor eiciency.

It should further be noted that' the pressure of the compressed gas is not transmitted to the liquid-bearing strata 12. Thus, there will be no tendency for the liquid to be forced into the strata eachetime the pumping mecha- VVterior of the casing and the liquid-bearing strata 12. This may readily be accomplished by controlling the pressure inside the casing l0 by means o f the valve 14. When a well is comparatively new, the normal differential pressure between the interior of the casing and the liquid-bearing strata is very high, and if this differential pressure is reduced, the producing life of the well is materially lengthened. It is thus an important feature of my invention that this differential pressure may be controlled by regulating the amount of pressure in the casing 1l.

The particular construction of valve mechanism illustrated is not claimed per se in this application, any pressure-operated valve which simultaneously opens the passage 53 and closes the vent openings being equally applicable to the pumping mechanism shown. Furthermore, any valve which performs these functions and which is situated in the lower end of the well and which is controllable from the surface of the ground might be utilized. The particular valve illustrated is operated from the surface of the ground merely by building up the pressure in the annular space 35, but electrically or mechanically operated valves might be substituted, these valves being operable from the surface of the ground.

The particular arrangement of tubing illustrated is another important feature of my invention, inasmuch as it is compact in design and gives the advantages above outlined relative to the regulation of dierential pressure and prevention of high pressure against the liquid-bearing strata of the well.

The particulaia'rrangement of tubing and pumping mechanism shown is also extremely valuable in increasing'the pumping efliciency, for it should be clear that it is not necessary to waste a large per cent of the gas in reducing the pressure sufficiently to allow liquid to enter the casing as is necessary in the ordinary form of gas-lift pump. I have found that the cost of lifting a unit volume of liquid is only a small fraction of the normal lift cost of other types of gas-lift and mechanically reciprocating pumps.

I have found the particular means of joining the plug member and the head member to be advantageous in forming a tight joint between these members, due to the fact that the packer 26 may be made to carry a portion or all of the weight of the primary tubing 20, thus insuring a fluid-tight joint between the members 23 and 28.

I claim as my invention:

1. In a displacement pump for pumping wells having a pump chamber formed therein, a compressed gas controlling valve comprising a valve body or head member including an intake passage communicating with a compressed gas supply, a valve chamber cent 'al with and communicating with said intake passage and communicating with the pumping chamber, a valve seat formed at the junction of said intake passage and said valve chamber a gas inlet valve operatively mounted in said valve chamber and including a stem arranged to form a piston in said-intake passage, a notch extending for a portion of the length of said stem, said notch arranged to permit the flow of compressed gas past said valve when said valve has moved a predetermined distance, and a valve head having a valve seat arranged to contact said valve body inlet passage seat and having` gas passages positioned upon its periphery, a plunger slidably mounted in said valve chamber and having gas passages positioned vupon its periphery, an inlet valve spring positioned between said gas inlet valve and said plunger, a plurality of vent passages communicating between said pumpingl chamber and the exterior of said displacement pump, and havingV valve seats; a plurality of vent passage valves, a valve member carrying said vent passage valves and engageable with said plunger, means pivotally mounting said valve member on said valve body for movement by displacement of said plunger to close said vent passages and a second spring means normally biasing said valve member to open said vent passages until the compressed gas pressure exceeds a predetermined value and displaces said inlet valve and said plunger.

2. In a displacement pump for pumping wells having a pumping chamber therein, a compressed gas controlling valve comprising a valve body including an intake passage communicating with a compressed gas supply, a valve chamber central and communicating with said intake passage and communicating with the pumping chamber,l u

vvalve seat formed at the junction of said intake passage and said valve chamber; va gas inlet valve operatively mounted in said valve chamber and including a stem arranged to form a piston in said intakeA passage, and arranged to move a predetermined distance before opening said inlet passage, and a valve head having a seat arranged to contact said valve body inlet passage seat; a plunger slidably mounted in said valve chamber, an inlet valve spring positioned between said gas inlet valve and said plunger, a vent passage having a valve seat, a vent passage valve, a valve member carrying said vent passage valve and engageable with said plunger, means pivotally mounting said valve member on said valve body for movement by displacement of said plunger to close said vent passages and a second spring means normally biasing said valve member-'to open said vent passages until the compressed gas pressure exceeds a predetermined value and displaces said inlet valve and said plunger. i

1n a displacement pump for wells having a pumping chamber therein, a compressed gas controlling valve comprising a valve body including an intake passage communicating with a compressed gas supply, a. valve chainber central and communicating With said iI1- take passage and communicating with the pumping chamber, a valve seat formed at the Junction of said intake passage and said valve chamber; a gas inlet valve operatively mounted in said valve chamber and including a stem arranged to form a piston in said intake passage, and arranged to move a predetermined distance before opening said inlet passage, and a valve head having a seat arranged to contact said valve body inlet passage seat; a plunger slidably mounted in said valve chamber, an inlet valve spring positioncd between said gas inlet valve and said plunger, a vent passage having a valve seat, a vent passage valve, a valve member pivotally mounted in said valve body and arranged to operatively contact said plunger and to operatively carry said vent passage valve, whereby When said valve member is in one position said vent valve is open and said inlet valve closed; and means for resiliently holding said valve lmember in position to open said vent passage.

In testimony whereof, l have hereunto set my hand at Los Angeles, California, this 22nd day of June, 1928.`

ART 1'1 F. WHITE.

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