US2220334A

US2220334A - Deep well pump

Info

Publication number: US2220334A
Application number: US197103A
Authority: US
Inventors: Einar O Holmberg
Original assignee: AO Smith Corp
Current assignee: AO Smith Corp
Priority date: 1938-03-21
Filing date: 1938-03-21
Publication date: 1940-11-05
Anticipated expiration: 1957-11-05

Description

Nov. 5, 1940- -E.. o. HOLMBERG DEEP WELL PUMP Filed March 21, less 2 Sheets-Shea?. l

@Ham/:erg INVENTOR.

Einar I I I I II I., I I I n r I 1 h I lb. I II,... ./IIIII. IIIII. ,I

ATTORNEY.

Nov. 5, 1940.

E.o. HOLMBERG DEEP WELL PUMP 2 Sheets-Sheet 2 Filed March 21, 193s 51ml O Holmberg 1NVENTOR.

ATTORNEY.

Patented Nov. 5, 1940 UNITED STATESl PATENT OFFICE DEEP WELL PUMP Application March 21, 1,938, Serial No. 197,103

Claims.

This invention relates to deep well pumps for pumping oil or other uids from deep wells.

An object of the invention is to provide an im-` proved deep Well pump which is electrically driven and which avoids the necessity for using the sucker rods that have heretofore been eX- tensively employed for actuating oil well pumps.

Another object of the invention is to provide an apparatus in which a power pump utilizes the well fluid to operate a fluid motor which in turn operates the well pump.

In accordance with the invention a low pressure large volume rotary power pump is driven by an electric motor and delivers fluid to a series of pistons in multiple, effecting reciprocation of the plunger of the Well pump which delivers a relatively small volume of iluid at relatively high pressure.

Other objects of the invention will be clear from the accompanying description and the drawings in which:

Figure 1 is a longitudinal section through the deep Well pump of this invention;

Fig. 2 is an enlarged longitudinal section" that used for-Fig. 5 and showing the valve seated at the other extremity of its travel;

Fig. 7 is a transverse section on the line 'I-l of Fig. 5; and

g Fig. 8 is a longitudinal section through another embodiment of the Dumping unit which may be more desirable under certain conditions.

In providin'g'an electric motor driven deep well pump the probleml of utilizing the high speed;

rotary drive for pumping has been a dilcult one to solve. If a rotary well pump is used, it will necessarily have small clearances in order to work.

against the high pressure head ofthe huid, and would soon be ruined by sand or grit in the crude D oil or liquid pumped. A centrifugalor'/`turbine type pump-Would be free from this trouble since clearances do not need to be kept small, butv these pumps are adapted to pump large quantities of uid against a low head and are not so suitable 5 for pumping a small quantity against a high (Cl. S-46) face of the ground. In this Way use is made of the superiority of power transmission by electricity as compared to transmission by sucker rods; the electric motor is directly connected to a high speed rotary pump which is of such nature as not to be injured by' the passage of sand or E 4,

'grit through it; and full advantage is taken of the Well recognized suitability rof reciprocating pumps for pumping from deep wells.

Referring to the drawings-in which the embod.

iments shown are adapted particularly to pump- 1 ing from oil Wells and particularly to Fig. 1, the pumping unit comprises a shell I from which an electric cable 2 and a tubing string 3 for the pumped fluid lead to the surface of the earth. An electric motor 4 is direct connected to the impeller of a turbine or centrifugal pump 5 which takes in crude oil through conduit 6 and dis` charges it through conduit 'I. In using this unit in a Well 8 the inlet 6 will be submerged a suitableydistance below the oil level 9. Conduit I terminates in port Ill in the reversing valve II. Conduits I2 and I3 lead from the reversing Valve I I to the upper and lower ends respectively, of cylinders I4, of which six are shown in the embodiment illustrated. These cylinders are arranged in line and are traversed by a piston rod I5 which carries pistons I6V reciprocable within the cylinders. n Suitable packings I'I seal the piston rod where it passes through the ends of the cylinders. 'I'he crude oil pump I8 for pumping crude oll to the surface of the ground comprises a cylinder I9, a piston connected to the piston rod I5, and ball .check valves 2 l, 22and 23. Conduit I2 communicates with the upper end of cylinder I9 through check valve 2l so that useis made of the pressure developed by rotary pump l to supply oil to the crude oil pump I8 on its -down stroke.

The reversing valve II comprises a valve stem v24, a disc shaped valve member 25 rigidly secured ,Y to thevalve stem, and annular valve members 26 respectively, with fluid conduits I2 and I3. 'I'he

valve seats

33 and 34 are somewhat larger than

valve seats

35 and 36 so as to give an unbalanced pressure tending to keep the valve seated in whichever position it may be.

When the valve occupies the position shown in Fig. 5, crude oil from the rotary pump 5 passes through conduit 1, and ports III and 32 to the conduit I3 which conducts it to the lower ends of the cylinders I4. Oil in the upper end of the cylinders I4 passes down conduit I2 and through port 3I to conduit 31 from which it is discharged back into the well. Under these conditions the pistons I6 and the piston rod I5 are driven up-l wards. The cylinders I4 areas large in diameter as the size of the Well permits and take crude oil in parallel from pump 5.l A large.vol ume of fluid is therefore required to cause substantial upward motion of the piston rod. Only a moderate pressure is required, however, to exert a very considerable force on the piston rod since the pressure is applied to the comparatively large areas of each piston and the forces ex:

erted on the pistons are all added together by 25.virtue of the attachment of all pistons to the common piston rod. Consequently the large volume of low pressure fluid from pump 5 is used to produce a considerable force on the piston rod I5, and this in turn `^is used to drive pump I8 to 30 pump a small volume of crude oill against the high pressure exerted by an oil column reaching vfrom the pump to the surface of the ground.

As the pistons I4 near the upper end of their stroke, the reversing valve is thrown to the posi- 35 tion shown in Fig. 6 by means which are described hereinafter. In this position the ow of fluid to cylinders I4 is'reversed and the pistons within the cylinders are forced downward, the

oil below the pistons being discharged back into o the well through conduit I3, the reversing valve,

and conduit 38.

The reversing valve is operated by the motion of the piston rod I5 to which an extension 39 is attached. A pin 4U passes through a slot 4I in rod 39 and through the intersection of two forked

toggle arms

42 and 43.

Slots

44 and 45 at the outer ends of

toggle arms

42 and 43 engage

xed pins

46 and 41. cause the toggle arms to depart as far as pos- 50 sible from the straight

line joining pins

46 and 41. The valve stem 24 is connected to the reversing valve mechanism by rod 49 with slot 50 through which pin 40 passes.

When the valve and the valve operating mechanism have the configurations illustrated in Figs. 3 and 5 the distribution of uid to cylinders|4 is such as to cause upward` motion of piston rod I5 and its extension 33.' No eiIeet upon the valve operating mechanism is produced until the 60 upward motion of the pistons brings the lower end 5I of slot 4I into contact with pin 40: 'I'his- 70 on the valve tends to keep it seated. Continued upward imotion of the piston. rod I5 and its extension 39 ultimatelycarries the

toggle arms

42 and 43 past their dead center position, after y which springs 48 cause them to move pin 40 rap- 75 idly upward. The pin comes into contact with."

Springs 48 tend to the upper end 52 of slot 50 and forces rod 49 and valve stem 24 upward thus throwing the reversing valve to its other position as shown in Fig. 6 and reversing the motion of the pump plunger. Toward the end of the downstroke of rod I5 the upper end of slot 4I engages pin 4!! and forces it downward past the dead center of

toggle arms

42 and 43, thus causing the valve to be shifted again.

In wells where salt water is present along with the oil the passage of a. mixture of the two through a centrifugal or turbine pump produces an emulsion which it is dimcult to separate into its l'constltuents. With the embodiment illustratedlinFlg. l, all the oil pumped to the surface by pump I8 has first passed through the rotary pump 5 and may have been emulsiiied to a greater or lesser extent. In the embodiment illustrated in Fig. 8 the pump I8 takes oil directly from the well through conduit 53 and pumps it to the surface. The centrifugal or turbine pump 5 simply recirculates crude oil taken from and discharged back into a region of the well above that which supplies oil to pump I8. By suitably restricting communication between these regions of the well only an insignificant amount of emulslfled fluid will nd access to pump I8 through conduit 53. If desired, an entirely closed cir- I pistons by the uid pressure will be added together, a reciprocating pump driven by the piston rod, said reciprocating pump being adapted to pump the desired quantity of well fluid against a pressure head corresponding to the height to which it is desired to pump the fluid, a rotary motor,-.a rotary pump driven by the rotary motor and adapted to pump fluid at a rate in excess of that-at which it is desired to remove fluid from the well but at a lower pressure than Awould suillce to elevate the fluid from the well, means to direct the fluid pumped by the rotary pump alternately to opposite ends of the cylinders in which the plurality of pistons mounted on the piston rod travel s'o as to produce reciprocating motion of the piston rod, an inlet from the well A to the rotary pump, and an outlet from the rotary pump to the means used to control the distribution of the uid which it pumps.

2. In a submersible unit for pumping fluid from 1 a. deep well the combination of a reciprocating pump adapted .to-pump well fluid at the desired rate against the necessary head, a rotary pump adapted to pump alarger quantity of well fluid against a. lower head, a rotary motor to drive the rotary pump, and a reciprocating hydraulic motor adapted to drive the reciprocating pump and to be driven by the fluid pumped by the rotary pump, the reciprocating hydraulic motor comdem, pistons movable therein, and a common piston rod to which'the pistons are secured.

3. A submersible pump for pumping fluid from a deep well which comprises a hydraulic motor 'zoY prising a plurality of cylinders arranged inV tanl With a plurality o f cylinders arranged in tandem. pistons movable within said cylinders, a common piston rod to Which the pistons are secured, a reciprocating pump driven by the motion of the piston rod, a rotary electric motor, a rotary pump driven by the rotary motor and operating on the iluid from the Well, a reversing valve for controlling the distribution of uid pumped by the rotary motor, fluid conduits from the reversing valve to the cylinders arranged in tandem, said conduits being arranged to conduct fluid to and exhaust it from the corresponding ends of all the cylinders, and means controlled by the motion of the piston rod .for throwing the reversing valve as the piston rod nears each end of its stroke, said rotary pump also supplying Well uid under initial low pressure to said reciprocating pump.

4. A submersible unit for pumping fluid from a deep Well, comprising an' electric motor, a reciprocating well pump, a reciprocating fluid motor for driving said well pump, and a high speed large volume low pressure rotary pump driven by said electric motor and operating on fluid from said well for driving said reciprocating uid motor.

5. A submersible unit for pumping uid from a deep well, comprising an electric motor, a reciprocating well pump, a reciprocating fluid motor for driving said well pump, a high speed large volume low pressure rotary pump driven by said electric motor and operating on fluid from said well for driving said reciprocating fluid motor, and means for supplying low pressure Well fluid from the rotary pump to the reciprocating Well pump.

EINAR O. HOLMBERG.