US2259020A - Apparatus for pumping wells - Google Patents

Description

Oct. 14, 1941. w. H. WINEMAN 2,259,020

I APPARATUS FOR PUMPING WELLS Filed Dec. 9, 1958 2 Sheets-Sheet l Oct. 14, 1941]. w. H. WINEMAN 2,259,020

I APPARATUS FOR I UMPING WELLS Filed, Dec. 9, 1938 2 Sheets-Sheet 2 r I a1 I i 20297222 8 71/061656 Zl/z'flema n awg.

.my invention may assume Patented Oct. 14, 1 941 APPARATUS FOR PUMPING WELLS Wade H. Wineman, Michigan City, Ind., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application December 9, 1938, Serial No. 244,783

11 Claims. (01. 255-16) .My invention relates to pumping apparatus, and more particularly to apparatus for pumping oil wells by means of so-called beam" well pumping equipment. From another aspect, my

invention relates more generally to devices for minimizing stresses between a device to be recipso important a factor, somewhat more power because 01 the operating cycle than is requisite to do the work of simply lifting the sucker rod line, the pump plunger and the oilwhich is pumped.

It is an object of my invention to provide an improved pumping system. It is another subject ;of my invention to provide-an improved device for incorporation in a "beam well pumping system which will free the latter from a number of its disadvantages. invention to provide an improved pump actuating a paratus. It is a further object of my invention to provide an improved device for reducing sucker rod peak loads and stress ranges in beamtype pumping systems. It is a still further obiect, but a more general one, of my invention to provide an improved arrangement for minimizing the stresses between a source of reciprocating motion and the v device which is reciprocated thereby. Other objects and advantages of my invention will hereinafter more fully appear.

In the accompanying drawings, in which for purposes of illustration one embodiment which in practice has been shown:

Fig. l is an elevational view, in asomewhat diagrammatic form, of a pumping system in which the illustrative embodiment of the invention is incorporated.

' Fig. 2 is an enlarged vertical sectional view through a stress-reducing cylinder and piston mechanism.

Fig. 3 is a view sin'iilar to Fig. 2: but showin parts in different relative positions. Fig. 4 is an enlarged detail sectional view showing a portion of the lower head of the cylinder It is another object of my mechanism of Fig. 2, the section being on the same plane as Fig. 2.

Fig. 5 is a fragmentary detail sectional view through the relief valve shown in elevation in i 2.

Fig. 6 is a view partially in section showing details of the pressure-providingmeans incorporated in Fig. 1.

Fig. 7 is an enlarged bottom view of the compressor cylinder shown in side elevation in Fig. 6.

Fi 8 is a central sectional view on the section lines 88 of Figs. 6 and "I.

There are different methods by which the high stresses produces through the operation of a beam type pumping apparatus may be reduced and the wide stress ranges which accompany the use of these devices may be narrowed. One of these'methodsconstitutes the subject matter of this present application.

According to a preferred embodiment of the present invention, a cylinder-and-piston stressreducing device is arranged between the beam of the pumping unit and the polished rod, and an arrangement is adopted which causes the piston practically to float somewhere between positions above and below the center of the cylinder. Of course, with diiferent cylinder proportions the zone of floating would be.diflerent. Ordinarily, the piston, when this element is connected to the polished rod, will, during the down-stroke of the sucker rod line, float in the cylinder in a rela-' tively high position therein compared with its position during portions, at least, of the up-stroke of the sucker rod line. A cushion of air or other suitable gas under sufficient pressure will be maintained beneath the piston, with the volume of this gas under pressure such that relative upward movement of the cylinder with respect to the piston will be attended by a pressure increase at a substantial rate. Accordingly, when the beam accelerates on the up-stroke and the piston tends to lag behind with relation to the cylinder,

there will be a definite rise in pressure over and above that required to balance the rod and fluid load, while when the beam moves on the downstroke, the piston will move up with relation to the cylinder and the air pressure under it will drop to a value which will substantially balance the rod load only, without an excessively long relative upward movement of the piston. Provision may advantageously be made for the con-' tinuous making-upoi' any fluid lost during the working of the device, and for the venting of any excess of pressure fluid provided. and for limiting, by such venting, of the relative upward travel of the piston. Furthermore, desirably, devices will be provided for effecting a positive cushioning of the piston in the event of extreme downward relative movement thereof, and in like manner there will be provision for effecting a cushioning of excess upward movements of the piston, should any occur, through suitable means. The source of pressure supply to the stress-reducing device may obviously be varied. but it will be found that a compressor operated ofi of the beam and having improved means for enabling a variation in the quantity of fluid pumped and for the lubrication thereof, will be highly advantageous.

Now referring to the structure specifically fllustrated in this application, it will be noted that the well I, containing a pump not shown, is adapted to be pumped through the reciprocation of a polished rod 2 which is connected by a suitable connecting device 3 to my improved stressreducing mechanism generally designated 4 and through the latterand a beam hanger 5 to a walking beam 6. The walking beam 5 is-pivotally supported upon a Sampson post I and is rocked about its pivot by a pitman 8 which connects it with a suitable beam driving unit; and one of these of conventional construction is shown at 9. Any suitable source of power. as for example a belt drive l from a motor or engine not shown, may be provided for the beam operating unit 5.

Referring now more particularly to, the structure of the device 5, it will be observed that this includes a cylinder element i2 having associated therewith an upper head l and a lower head it. The bore l5 of the cylinder element l2 contains a piston l5 which has a piston rod l'I passing through a suitably packed opening I! in the lower head It and secured by the connecting device 3 to the polished rod line. The upper head [3 is connected by the connecting element 20 to the beam hanger 5. There is provided near the lower end of the cylinder element I 2 a lateral connection 22 connected herein through an elbow 23, a flexible conduit 24, piping 25 and a'further flexible conduit 25 to 'a small receiver tank 21, and to the discharge line 25 from a compressor, generally designated 29, whose details will later be described. The receiver tank may be unnecessary, and it may be made of variable effective clearance volume by. filling it to different degrees witha suitable liquid.

The lower head ll of the cylinder is provided with a check valve controlled passage 3| opening into the lower end ,of the cylinder at one of its own ends and connected with a passage 32 opening into the port 22 at its other end. A check valve 33 associated with this passage permits the delivery of fluid from the lateral supply connection through the passages 32 and 3| to the bottom of the cylinder bore l5 while preventing reverse flow. There is thus assured under allv conditions a definite cushion between the lower cylinder head and the piston, and access of fluid below the piston even if the latter should come to rest on the lower cylinder head during some period of shut-down.- The upper head ii of the cylinder is provided with a check valve controlled passage 35 having associated therewith a check valve 35 which permits inflow of fluid from an atmospheric connection 31 tothe top end of the cylinder while-preventing reverse flow. This insures a cushion at the top end of the cylinder and renders this cushioning not dependent on leakage past the piston i5.

The cylinder is provided at a point relatively near the longitudinal center thereof with a lateral port 45 provided with a spring-loaded relief valve 46 controlling the efllux of air from the cylinder bore to the atmosphere through the port 45, and preventing a reverse flow through the port 45. This may be loaded to a pressure, say; from five to fifteen pounds per square inch, and as will later be apparent serves to regulate the cushioning in the top of the cylinder and the relative movement of the piston upwardly.

The'effective area of the lower side of the piston I6 will be so determined as to provide, with the pressure which is to be maintained in the lower end of the cylinder bore, an adequate force to balance the normal rod load with the piston in a position slightly below the port 45. The volume of the air between its source of supply and the bottom of the piston l6, will be so determined that the relative upward movement of the cylinder with respect to the piston during the raising of the sucker rod line will, materially-before the piston approaches closely the lower head of the cylinder, cause the building up of a pressure suflicient to sustain the maximum load imposed by the weightof the rod line, the work of accelerating the latter and the work of raising the oil that ispumped. It will be evident that with such a construction as is described, the piston it will, at a point perhaps half-way in the upward movement of the beam hanger 5, occupy a position possibly as fardown as that shown in Fig. 3; while during the downward movement of the beam hanger 5, the piston may move upward momentarily as far a the relative position shown in Fig. 2, although it"is unlikely that it will occupy a position highertha'n necessary merely to crack or partially uncover the port 45, provided the rate of air supply is properly controlled.

It will be evident from what has been said that the rate ofair supply should be rather precisely controlled'with this apparatus, and for this purpose I have provided a" pump or compressor operated in synchronism with the movements of the stress-reducing device and adapted to furnish pressure fluid in desired quantity to the space in communication with the volume beneath the piston [5 once during each complete cycle. For this purpose, the compressor or pump mentioned,

. which is, as above noted, generally designated 29,

is shown as of the beam-actuated, air-cooled type and includes a cylinder 55 in which a trunk piston 5| is reciprocable. A suitable mounting for the cylinder, by means of the legs 52 and holding bolts 53, is provided upon a frame '4. herein shown as secured to the side of the Samp: son post I. The piston 5| has a wrist pin 55, connected by a connecting rod-55 of adjustable length pivotally with a block 51 re'movably heic. by bolts 58 to the beam 6. The connecting rod 56 is made up of a lower portion 50 having a splined connection at 6| with a reduced end 62' of a member 52 which is bolted at 53 to an upper tubular portion 54 pinned at 65 to a pivot member 65 pivotally supported on a pin 51 carried by the block 51. A rain shield 68 is adjustably mounted on the rod section 50, and the eff :tive length of the connecting, rod may be varied to vary the clearance volume of the compressor by the turnbuckle element 10 threadedly engaging the upper end of the rod portion 55 and an intermediate threaded portion 62 of the rod element 62. A lock nut H to maintain the parts in adjusted position is provided. The compressor ,may be provided with any suitable inlet and discharge mechanism and is herein shown as having a poppet-type inlet valve Ii held closed by a spring 16 and a poppet-type discharge valve 'l' l held closed by a spring 18. The construction is municates with the compressor discharge line 28." Lubrication of the compressor piston, cylinder;

wrist pin, and connecting rod bearing may be eifected by maintaining a suitable quantity of oil upon the top of the piston within the upwardly extending skirt of'the cylinder. The speed of reciprocation of the piston, frequently less than 50 feet per minute, is insufllcient to create any danger of throwing the oil out of the top of the cylinder. By the adjusting mechanism III, the quantity of fluid delivered can be regulated, and if desired, it is of course possible to bleed oil from the system, at a point short of the cylinder l2, any quantity of fluid in excess of the needed amount. However, with a proper adjustment of the parts, it will be found that the venting of the fluid which will normally occur in small quantity during each cycle when the port 45 is uncovered by the lower end of the piston IE, will adequately care for the disposal of any excess pressure pumped by the compressor 29. The provision of the clearance tank 2'! enables the increasing of the volume of fluid within the system if desired, but ordinarily this is not requisite.

The compressor 29 may obviously be arranged either to make its discharge stroke during the up-stroke of the device 4 or tomake its discharge stroke during the down-stroke of the latter, it simply being necessary to make appropriate adjustments with respect to the quantity of fluid delivered and available clearance volumes, including the working clearance of the compressor, to take care of the situation. Obviously, with the compressor discharging during the down-stroke I of the apparatus 4, the discharge pressure of the compressor 29 will be considerably less than is requisite when the compressor discharges during the raising of the device 4, and so that arrangement is shown in Fig. l. A position of the compressor at the other side of the Sampson post would result in discharge on the lifting move-' ment of the device 4.

The mode ofoperation of this device will be clear from what has already been said. The clearance volume between'the compressor and the lower side of the piston It will be small enough so that there will be a deflnite rise in pressure over and above that required to balance the rod and fluid load when the beam accelerates on the up-stroke, and while the cylinder moves upward relative "to the somewhat retarded piston. The increase in pressure that will take place will be sufficient to raise the sucker rod line and the fluid load. Conversely. when the beam moves on thedown-stroke, the piston, if it has not indeed already moved into its highest relative position with respect to the cylinder, will quickly attain to a position uncovering or partially uncovering the port 45, and an amount of air will then pass through the relief valve 46 until the pressure below the piston i6 falls enough so that the piston will again cover the port when subjected only to the weight of the rod line and associated parts. The amount that will pass through the port 45 on each cycle of operation will be governed largely by the output ot'the make-up compressor supplying the air. 'As the piston moves above the vent port, any

' cated and a walking beam for reciprocating said 3 excess volume of air will be discharged through the vent port. when the piston moves below the vent port further escape of fluid will be pre-' vented, and upon the lifting of the cylinder'by the beam, the piston will lag behind until the reduction in volume of the fluid in the total clearance space results in the production. of a pressure sufllcient to lift the'rods and their load. 1

During the latter part of the upstroke, the slow irig down of the movement ofthe cylinder and the cessation oi the need to supply power to accelerate the rods, etc., and the higher pressure beneath the piston will cause the piston to move fasterthan the cylinder, and the piston will rise from its position shown in Fig. 3 to that of Fig. 2 probably by the end or the pumping stroke. The valve device 45 will prevent more fluid from escaping than isnecessary-to maintain the desired volume following upon the introduction of the additional quantity supplied by the working stroke of the piston 5i. 7 a

- It will be apparent that I have provided an arrangement'in'which the shocks of pumping will be largely eliminated, that the maximum stress will be reduced, that there will be an automatic departing from its spirit or the scope of the appended claims. 1

' What I claim as new and desire to secure by Letters Patent is: a

1. In an apparatus of the character described, the combination with a member to be recipromember, 0! a fluid cushioning means connected between the operating end of said walking beam and said member to be reciprocated and'including a cylinder containing a reciprocatory piston,

and means for controlling the pressure of the fluid in the cylinder at the opposite'sides of said.

the combination with a member to be recipro-' cated and a walking beam for reciprocating said member, a: a fluid cushioning means connected between said walking beam and said member to be reciprocatedand including a cylinder containing a reciprocatory' piston and means for controlling the pressure of the fluid in the cylinder at the opposite sides of said piston, said fluidcontrolling meansincluding a piston-controlled port opening to atmosphere and communicating with the cylinder at a point to be overrun by said piston during its travel in either direction of reciprocating movement.

3. In an apparatus. of the character described, the combination with a member to be reciprocated and a walking beam for reciprocating said member, of a fluid cushioning means connected between the operating end of said walking beam and said member to be reciprocated and includlower side of said piston, and means for further controlling the pressure of the fluid in the cylinder at the opposite sides of said piston including automatic check valve means opening inwardly into communication with the cylinder ends for'supplying fluid thereto.

4. In an ,apparatus of the character described, the combination with a, member to be reciprocated and a walking beam for reciprocating-said member, of a fluid cushioning means connected between said walking beam and said member to be reciprocated and including a cylinder containing a, reclprocatory piston, means for controlling the pressure of the fluid in the cylinder at the opposite sides of said piston, said fluid-controlling means including a piston-controlled port opening to atmosphere and communicating with the cylinder at a point to be overrun by said piston during its travel in either direction of reciprocating movement, and means for supplying fluidat a relatively high pressure to the lower end of said cylinder at the lower side of said piston.

5. In an apparatus of the character described, the combination with a member to be reciprocated and a walking beam for reciprocating said member, of a fluid cushioning means connected between said walking beam and said member to be reciprocated and including a cylinder containing a reciprocatory piston and means for controlling the pressure of the fluid in the cylinder at the opposite sides of said piston, said fluidcontrolling means including a. piston-controlled port opening to atmosphere and communicating with the cylinder substantially midway between ,its ends and an outwardly opening check valve for controlling the flow of fluid through said port. 6. In an apparatus of the character described,

' the combination with a member to be recipropiston and means for controlling the pressure of the fluid in the ends of said cylinder at the opposite sides of said piston including a valve-controlled vent' passage and means for delivering fluid to said cylinder including a fluid pressure generating device actuated by said walking beam and operatively connected to the latter at the same side of its pivot as said cushioning device, said fluid pressure generator comprising a stationary cylinder, a piston reciprocable in said last mentioned cylinder and a pivoted connectin rod connected between said walking beam and said last mentioned piston, and fluid conducting means extending'from said last mentioned cylinder to said cylinder of said cushioning device at a point spaced from one end thereof and also at its end, in the last case through a valve controlled passage, said fluid conducting means ineluding a'fiexible conduit.

9. In a well pumping apparatus, the combination with a polished rod and an oscillating beam,

, of apneumatic cylinder and piston mechanism 1 piston when the same is in a relatively high position with respect to said cylinder.

10. In a well pumping apparatus, the combina tion with a polished rod and an oscillating beam, of means forvoperatlvely connecting said beam and polished rod including a cylinder and piston mechanism, a pressure system including a pump actuated by said beam, means for connecting said pressure system with the cylinder of said cylinder and piston mechanism, said pressure system enbeam and: another connected to said member to be reciprocated, and means for controlling cushioning pressures including a fluid pressure generator actuated by said walking beam for supplying fluid under pressure to one. end of said cushioning device and means for venting said end on a predetermined relative movement of said parts.

7. In an apparatus of the character described,

the combination with a'member to be reciprocated and a walking beam for reciprocating said member, of a pneumatic cushioning device. suspended from the operating end of said walking beam and operatlvely connected to said member to be reciprocated, said cushioning device comprising a cylinder containing a reciprocatory piston and means for controlling the pressure of oi said cylinder.

8. In an apparatus of the character described,

the combination with a member to be reciprocated and a walking beam for reciprocating said member, ofa pneumatic cushioning device suspended from the operating end of said walking 'beam and'operatively connected \to saidtmember to be reciprocated, said cushioning device comand piston during the lifting movement of the beam tostart and accelerate the polished rod and during the lowering movement of the beam to drop to a pressure approximating the dead weight of the polished rod and the structure supported thereby and piston controlled means for control ling the pressure in said pressure system.

, 11. In an apparatus of the character described, the combination with a member to be reciprocated and a walking beam for reciprocating said member, of apneumatic cushioning device having relatively movable parts and suspended from the operating end of said walking beam and operatively connected to. said member to be reciprocated, and a fluid pressure generator actuated by said walking beam and having fluid deliveryconnections-leading therefrom to said pneumatic cushioning device, said pneumatic cushioning 'devic having provision for the venting therefrom of cushioning fluid in a predetermined relative position of its parts and said fluid pressure generator delivering during each cycle of beam movement make-up fluid to said cushioning device.

12. In an apparatus or the character described, thecombination with a member to be reciprocated and a walking beam for reciprocating said member, of operative connections between said beam and member including a pneumatic cushioning device having relatively movable parts and. a beam-actuated source of pressure fluid operatively connected thereto, the volume within said device and in the connections between the same and said source of pressure fluid so small that substantial pressure changes attend relative movements of the parts of said cushioning device,

prising a cylinder containing a reciprocatory J5 said cushioning device having pressure venting means made effective in certain relative positions member, of a pneumatic cushioning device suspended from the operating end of the walking beam and operatively connected to said member to be reciprocated, and a fluid pump actuated by said walking beam and operatively connected to the latter, said cushioning device having means for the discharge of fluid therefrom during each cycle of operation of the beam and said pump delivering to said cushioning device make-up fluid ,during each cycle of operation of the beam.

14. In an apparatus of the character described, the combination with a member to be reciprocated and a walking beam for reciprocating said member, of a fluid cushioning means connected between the operating end of said walking beam and said member to be reciprocated andincluding a cylinder containing a reciprocatory piston, meansfor supplying pressure fluid to the lower end of said cylinder at the lower side of said .piston, and means for controlling the pressure of the fluid in the cylinder at the opposite sides of said piston including automatic check valve means opening inwardly into communication with each end of said cylinder, said check valve means at one end of said cylinder controlling communication of said cylinder with atmosphere and said check valve means at the opposite'end of said cylinder controlling communication of said cylinder with a source of pressure fluid.

15. In an apparatus of the character described,

the combination with a member to be recipro-- cated and a walkingbeam for reciprocating said member, of a fluid cushioning means connected between the operating end of said walking beam and said member to be reciprocated and including a cylinder containing a reciprocatory piston,

means for supplying fluid at a relatively highpressure to the lower end of said cylinder at the lower side of said piston, said last mentioned means including a valve controlled passage communicating with the lower end of said cylinder and simmer passage communicating withsaid means for supplying cylinder at a point spaced from the lower end thereof, and means for controlling the pressure in the lower end of said cylinder including a port opening to atmosphere and communicating with said cylinder at a point overrun by said piston.

16. In an apparatus oithe character described, the combination with a member to be reciprocated' and a walking beam forreciprocating said member, of a fluid cushioning means connected between the operating end of said walking beam and said member to be reciprocated and including a cylinder containing a reciprocatory piston, fluid at'a relatively high pressure to the lower endof said cylinder at the lower side of said piston, said lastmentioned means including a passage communicating with the lower end of said cylinder and a further passage communicating with said cylinder at a point spaced from the lower end thereof, automatic check valve means opening inwardly for controlling fluid flow through said passage communicating with the lower end of said cylinder, and means'for controlling the pressure in thelower end of said cylinder including a piston-controlled port opening to atmosphere and communicating with said cylinder substantially midway between its ends and an outwardly opening check valve for controlling the flow of fluid through said port.

17. In combination, a member to be reciprocated, a walking beam for reciprocating said member, and fluid-cushioning means connected between the operating end of said walking beam and said member to be reciprocated and including a cylinder containing a piston, said cylinder and piston relatively reciprocable, means for supplying pressure fluid to the lower endrof said cylinder including a connection for pressure fluid opening into the side of the cylinder at a point above the bottom of the latter and a passage 1 extending from said connection into communication with the bottom of said cylinder,'said passage

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