US1830941A

US1830941A - Well pumping system

Info

Publication number: US1830941A
Application number: US261808A
Authority: US
Inventors: Frederic W Hild
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-03-15
Filing date: 1928-03-15
Publication date: 1931-11-10
Anticipated expiration: 1948-11-10

Description

Nov. 10, 1931. F. w. HILD WELL PUMPING SYSTEM Filed March l5, 1928 2 shee's-sheet 1 INVENTOR ATORNEY Nov. 10, 1931-. F. w. HILD 1,830,941

WELL PUMPING SYSTEM Filed March 15. 1928 2 Sheets-Sheet 2 INVENTOR AT'TORNEY Patented Noir'. .10, 1931 W. BILD, F LOS ANGELES, CALIFORNIA wenn PUMPING sYs'riun Application led March 15, 1928. Serial No. 261,808.

This invention relates generally to pumping systems and more particularly to longstloke pumping systems for oil wells and the li e. In my copending application, Serial No.

193,224, filed May 21, 1927, I have shown a long-stroke umpin system comprising apparatus an contro which is particularly adapted to be, utilized for pumping oil wells and the like, wherein a pair of motors are connected to two sun-gears, or end elements, of a planetary gear system forming a differential gear set. The. middle element, or

planetary member, of the differential gear set is connected to operate a cable winding drum, which actuates a cable that is connected to a pump plunger. A reciprocatory motion is imparted to the plunger by periodically reversing the direction of rotation of the drum. In this particular instance, the reversing of the drum is eiected by alternately changing the relative speeds of the motors.'

My copending application, Serial No. 221,-

418, filed September 23, 11927, shows another long-stroke pumping system wherein a special form of diierential gear transmission with a single driving motor is utilized to actuate a cable winding drum to which the pump plunger is connected. In this instance, reversal of the drum is efected by reversing the direction of rotation ofthe motor by means of an oscillator mechanism interposed between the drum and a reversing type controller.

The present invention provides a longstroke pumping system embodying a part of v the apparatus shown in the latter application,

and additional apparatus that will be described in detail in the subsequent paragraphs of this specification. v

Among the many important problems confronting the oil industry is that of economically and eiiiciently pumping the deep wells that are now in use. There are two general methods of obtaining oil from the ground, one, mechanical pumping, the other, raising the oil by compressed gas or air.

, Mechanical pumping is in greater use and is in general, the more economical method. Long-stroke mechanical pumping systems, as provided in the hereinbeforc mentioned copending applications, eliminates many ofthe di'liculties and improves the eiii'ciencyof mechanical oil pumping systems.

The hazard of back pressure on the produc` ing sands inherent in the as or air lift, is

Y. not present'with mechanica pumping which on the contrary augments the natural iiow 'oir' the iiuid into the well by exerting suction action. v The difficulties due to variable and uncertain submergence attendant upon the gas lift'- method are absent from mechanical pumping.

On the other hand, the gas lift increases the recovery of natural gasoline. Furthermore, the gas lift can continuously apply its lifting power, whereas the single acting. mechanical pump is limited to one half the time, namely the lifting stroke.

It is the object of this invention' to` provide a pumping system combining the best features of the gas lift and the mechanical pump and which shall have mutual and automatic control of both.

-The introduction of compressed gas ata point below the fluid level in a well, results in apparently stretching the Huid column without increasing its weight, by converting the fluid into a chain of bubbles reaching to the discharge line at the surface. Conse- A quently in the pumping system of this invens tion, the weight to be moved and hence thm size and strength required of the mechanical pumping means will be greatly lessened.

Another object of the invention is to provide for controlling the operation of a reciprocatory pump plunger by means of an auxiliary work device connected in the pumping system and disposed to be driven by the energy stored in the plunger during the pumping stroke. Y

Another object ofthe invention is to provide for operating a plurality of work de vices from the same motor and causing the work devices to control the operation of each other.

This invention accordingly is disclosed in the embodiment thereof shown in the accompanying drawings and comprises the features of construction, the combination of elements,

. and lthearrangement of parts which will be exemplified in the structure hereinafter set forth, and the scope of the application of which will be indicated in the claims.

Referring-to the drawings, Figure 1 is a -view in elevation, and partly in section, of a plunger type pumping system constructed in accordance with the present invention;

Fig. 2 is a cross-sectional view in elevation of a coupling shown in Fig. 1; and

Fig. 3 is a plan view of the pumping 'system shown in Fig. 1 with the addition of other apparatus to form a complete system embodied in the present invention.

Referring to Fig. 1 of the drawings, apparatus embodying the present invention may be applied to an oil well having the usual string of casing 1 suspended therein, the lower end of the casing terminating at the point near the strata of oil bearing sand 2.

In order to lift the iuid from the strata of oil bearing sand to the surface of the ground, a plunger pump is provided comprising a string of pump tubing 3 within the casing 1 and a working barrel or pump cylinder 4 to which is attached a perforated strainer 5 for admitting oil or other liquid, and excluding sand from the working barrel 4.

In order to raise the iuid which enters the working barrel 4, a plunger 6 with a ball valve 7 is provided and disposed to be reciprocated within the working barrel 4 by means of a string of pump rods 8. attached to a polish rod 9 which extends through a suitable stuling box 11.

The usual type of standing valve 12 is provided in the lower extremity of the working barrel 4 to permit the iuid to enter the pump barrel 4 and to prevent a return iow of Huid from the barrel 4 during the downward stroke of the plunger.

As will be observed from the drawings, a second string of well casing 14 extends from the surface to a point near the working barrel 4 where it is coupled to the tubing 3 by means of a reducer coupling 15.

The constructional details of the coupling 15 are shown in Fig. 2. The upper end of the tubing 3 is attached to the lower reduced end of the coupling 15 at 16` making" a gas or liquid tight joint. The upper end of the coupling is provided with screw-threads at 17, disposed to engage the threaded portion of the well casing 14 and is also provided with a cylindrical seat 18 to receive the lower Unthreaded end of the tubing 3. The lower portion of the tubing 3 contains a 'plurality of perforations, shown at 19 to afford communication from the tubing 3 into the casing 14.

The auxiliary casing 14 is provided with a cap 21 at its upper end which is provided with a suitable packing through which the tubing 3 passes. As shown, this particular construction forms an annular space between the casing 14 and tubing 3 that is utilized to retain as or air under pressure, as will be referred to in greater detail hereinafter.

Natural gas or air under pressure may be admitted to the casing 14 through a pipe 22 and valve 23, which are secured to the casing cap 21 by means of the flange coupling 24. A pressure gauge 25 is provided for 4indicating the gas or air pressure within the casing The pump tubing 3, which extends through the stufiing box in the casing cap 21 is provided with a cap 26 which is adapted to support the stuiiing box 11. The fluid which is raised by the plunger 6, or by the combined action of the plunger and compressed air or gas, is discharged from the cap 26 through the valve 27 and pipe 28 into any suitable receptacle such, for example, as a tank or an oil gathering line.

A pipe nipple which connects the valve 27 to the tubing cap 26 is tapped to receive an air vent pipe'29 that is provided with a controlling valve 31, the purpose of which will be described in detail'hereinafter.

In order to impart a reciprocating motion to the pump plunger 6, the polish rod 9 is connected to a rotatable drum 32 by means of a exible cable or wire line 33 which passes over a sheave wheel 34. The sheave wheel 34 may be supported in any convenient manner such, for example, as by an ordinary well derrick or by any other suitable structure.

In order to aotuate the drum 32, a suitable motor driven reduction gear mechanism 35 is provided, together with suitable control vvthat are disposed to engage the sprocket wheels 41 and 42, rotatably mounted on the shaft 36.

In order to hold the hoist drum 32 in any desired position whenvthe pump is not in operation friction brake bands 43 are provided. The operation of the bands 43 may be controlled in any desired manner such, for example, as by a well known manually operated lever system or an electromagnetic control.

The sprocket 41 is connected by a chain 44 to the driving sprocket 45 of the gear mechanism 35. In this embodiment of the invention, the gear mechanism shown, is a modified form of the well known double drive differential type that is used for earth .of bevel sun-gear wheels 46 and 47, rotatboring and the like, and isladapted for single motor operation. The gear mechanism 35 comprises a pair ably mounted on a shaft 49. A spur gear 51 1s securely keyed to the sun gear 46 and 1s disposed to mesh with the driving p1n1on 52 which is mounted upon the drive shaft 53. The sunar wheels 46 and 47 are each provided wit an extended sleeve portion which serves as quill bearings surroundmg the shaft 49 and are rotatably supported in suitable bearings in the gear case 54, as shown. The sleeve portion of the sun gear 47 is extended beyond the gear case 54 to receive the sprocket 55 which is securely ke ed thereon. v

he planetary element of the differential mechanism comprises spider 56, and a plug rality of bevel pinion wheels 57 rotatably mounted on pinion shafts 58 and disposed to -mesh with the sun-gear wheels 46-and 47.

The spider 56 is secured to the shaft 49 which is rotatably mounted in the sleeve extensions of the sun-gear Wheels 46 and 47. In order to control the operation of the differential planetary element or spider 56, the shaft 49 1s rovided with a friction brake 59.

n this embodiment of the invention, the prime mover for driving the gear mechanism 35 is an induction motor 61 of the squirrel cage type and is connected to the pinion shaft 53 by `the coupling 62. The motor 61 is disposed to be connected to a power source such as conductors 63, by means of a switch 64 andl an auto-starter 65.

In order to control the operation of the planetary element 56 of the differential gear mechanism 35, to obtain rotation of the drum 32 in the desired manner to reciprocate the pump plunger 6 a work device 66 is provided. As shown the driving sprocket wheel 68 of the work device 66 is connected for operation to the gear 35 by means of a chain 67. The work device 66 may be a pump for handling the Huid raised from the well or a compressor for forcing gas under ressure into the annular space' formed by t e casing 14 and tubing 3, each of which, operating as a control device, will be described in detail hereinafter.

The discharge of t-he work device 66, is controlled by a three-way rotary valve 69.

Since valves of this type are well known inv the art, a detailed view of this lparticular .piece of apparatus has not been shown.

However, the valve comprises an outer box or case, having an inlet opening and two discharge openings threaded to receive pipe. The case is bored to receive a rotatable cylinder member with ports and passages arranged so that by rotating -the cylinder vin one direction, the inlet will communicate with one discharge opening and close the other discharge opening, and, by rotating the valve in the opposite direction, the first mentioned discharge opening is closedand the second mentioned opening is connected to aii'ord communication with the inlet.

It will be readily understood that by utilizing a control device such as the'rotary valve 69 the Work device 66 may be loaded j to such an extent as to cause the'sun-gear wheel 47 of the gear mechanism 35 to remain stationary or run very slowly depending upon the amount of load imposed upon the planetaryelement 56 by the hoisting drum 32. Vhen the motor 61 is rotating at a substantially constant speed in one directionv only, the planetary element '56 will rotate in the same directlon if the sun gear 47 is stationary or rotating at a slower speed than the driven sun-gear Wheel 46, which will operate the hoist drum 32 and therefore the pump plunger. Under the same operating conditions for, the motor, if' the sun-gear' wheel 47 is permitted to rotate reducing the load on the work device 66, the planetary element 56 will be reversed by the weight of the pumping' string and conse uently 'permits the drum 32 to unwind until t e pump plunger reaches the bottom of its stroke.

It is therefore apparent that by automatically. controlling vthe discharge and consequently the loading' of the work device 66 in accordance with the number of drum rota;-

aov

tions, the pump plunger will be eriodically to state that it comprises a driven gear train which upon a certain predetermined number of revolutions in either direction of rotation, causes a second element 'to be automatically revolved a partial revolution. The second element has considerable momentum and, therefore, is capable of exerting a comparatively high turning torque which may be utilized to operate a motor controller or a valve mechanism such as described hereinbefore.

As shown, the torque shaft upon which r the sprocket, 72 is secured is connected to the operating sprocket 73 of the three-way valve 69 by means of a chain 74.

The operation of the oscillator 71 is effected by connecting the gear train actuating sprocket 75 to the drum sprocket 42 by means of a chain 76. The ratio of one sprocket to that of the other being such as to allow a suflicient number of drum revolutions to make a complete pumping stroke before the torque shaft and sprocket 72 of the oscillator 71 is actuated to reverse the rotary 4valve 69.

It will be observed that the intake port of the rotary valve 69 is connectedto the dis'- charge port of the work device 66 by means of a pipe 77 and controlling valve 78.

A pressureV gauge 79 is provided for indicating the discharge pressure of the uid or gas through the pipe 77. rIlhe pressure readings of the gauge 79 will also indicate the pull on the chain 67 and on the Wire line or cable 33 which will serve as an indirect measurement of the weight supported by the wire line 33 `during pumping or hoisting operations. l

It is to be understood that the invention as shown and described is suitable for pumping a well by either a mechanical lift method or by a. combination mechanical lift and gas or air lift method as v hereinbefore described, and, in addition, without change or modification the system may be utilized to perform the necessary' hoisting operations such, for example, as hoisting rods and tubing or making repairs which may require the use of hoisting equipment.

The operation of the system will first be described when operating as a combination mechanical pumping lift and gas lift system. In this event, the work device 66 is assumed to be a compressor forl supplying gas or air under pressure to the casing 14. The intake of the compressor 66, which is controlled by the valves 81 and 96, may be connected to any suitable source of natural gas supply such as tank 95, valve 81 being kept closed. One of the discharge ports of the rotary valve 69 is connected to the casing cap 21, through the valve 85, T 86,

pipes

87, 88 and 22. It will be observed that the T 86 in the discharge line is connected to a pressure tank 89, through pipe 91 and pressure control Valve 92 and that the other discharge port of the rotary valve 69 is connected to the pressure tank 89 through the valve 93 and pipe 94.

In order to set the system in operation, the clutches 38 and 39 are moved to the illustrated or disengaged positions, which allows the sprockets 41 and 42 to rotate freely on the drum shaft 36. The drum 32 is held in a fixed position by operating the brake band 43to the holding position. The motor 61 may then be set in operation by closing the switch 64 and operating the auto-star` er 65 in the usual manner. Since the sprocket 55, which is actuated by the sun gear 47, is connected to the compressor, the load thereon is greater than the friction load of the sprocket 41, which is connected to the sprocket 45 by means of the chain 44, and therefore, the planetary ele' ment 56 of gear mechanism 35 will revolve freely and no power will be transmitted to the compressor.

In order to set the compressor in operation, the brake 59 on the shaft 49 is actuated to its holding position, and stops the movement of the planetary element 56, and power from the motor 61 is transmitted to the compressor through the pinion 52, ear wheel 51, sun gear 46, planetary pinions 5 ,sun gear 47, sprocket 55, and chain 67 to the sprocket 68 on the compressor crank shaft.

Since it is necessary to impose a heavy load upon the compressor 66 to eilect the operation of the hoisting drum 32 as hereinbefore described, the compressor intake valve 96,

discharge valves

78 and 93 are opened and the rotary. valve 69 positioned by hand to discharge through valve 93 into the pressure tank 89.

The operation of the compressor 66 is con tinued in`this manner until the pressure in the tank 89 increases to the required amount which is a higher pressure than that required within the casing 14. The rotary valve 69 is then rotated by hand soas to permit the compressor 66 to discharge through the valve 85 and

pipes

87, 88 and 22 into the well casing 14. When the pressure within the casing 14 rises to a certain predetermined value the reducing valve 92 which controls the discharge from the high pressure tank 89 is released and therefore the quantity of gas supplied to the casing 14 is also increased. It will be readily understood that since the dicharge from the high pressure tank 89 is controlled by the existing pressure in the well casing 14 a comparatively slow discharge through the valve 92 will take place so long as the casing pressure does not fall below a certain value; also that the consequent pressure reduction in the tank 89 will not be great enough to'relieve the load upon the compressor 66 to such an extent as to prevent operation of the drum 32 as hereinbefore described.

In order to set the drum 32 in operation to actuate the pump plunger 6. the clutch 38 is closed to engage the sprocket 41, and the drum brakes 43 and 59 are released. Since the compressor 66 is discharging against a low'pressure head in the casing 14, the planetary element 56 cannot revolve to operate the drum 32 as the power required to hoist the pumping string, comprising the plungerv 6 and rods 8, is greater than the compressor load. Therefore, in order to load the compressor the rotary valve 69 is rotated by hand to again discharge into the tank 89 which causes the sun gear 47 to slow down and ultimately stop when the compressor load becomes greater than the pump load.

When the speed of the driven sun-gear wheel 46 becomes greater than the speed of the sun-gear wheel 47 which revolves in opposite direction, the planetary element 56 will revolve in accordance with the well known action of the diiferential.

Power is then transmitted through the planetary shaft 49. sprocket 45, chain 44 to the 'driving sprocket 41 of the hoist drum 32. The operation of the hoist drum 32 will raise the pump plunger 6 until it reaches o mit the planetary element 56 to revolve in a reverse direction, beingl reversed by the power transmitted throng the drum 32 by the Weight of the pumping string. Since the energy stored by the pumping string during the upward stroke reaches a high value the power transmitted back through the plantetary element 56 is applied directly to the sun-gear wheels 46 and 47 and therefore the sun-gear wheel 47 is driven at a speed controlled by the load at the compressor 66.

It will be readily understood that by regulating the discharge of the compressor 66 by ad]usting the valve 85 the descending speed of the pumping string can be controlled as desired.

When the pumping string reaches the bottom of the stroke the oscillator 71 is operated and consequentl the rotary valve 69 is actuated to again direct the discharge of the compressor 66 into the high pressure tank 89 which immediately causes the planetary element 56 to revolve and hoist the pump plunger 6 in the same manner as hereinbefore described.

It will be apparent that the operation of the well pump may be controlled by utilizing work device 66 as a reciprocating pump instead of as a compressor 66. In this event the pump 66 is shown connected directly to the casing cap 21 through

pipes

82, 83, 84 and 22 and valve 23.

In operating the system, the motor 61 and ump 66 are set in operation as described Eereinbefore with the hoisting drum 32 held in a fixed position by the brake 43. It will be readily understood that a quantity of iiuid must be supplied for controlling the operation of the pump 66 until the Well pump or plunger 6 has operated long enough to lift the iiuid in the well to the surface. The

pump 66 is, therefore, connected to the storage tank 95, through the valve 96 as shown. In this instance, the tank 95 contains a supply of liquid, preferably oil and by closing

valves

81, 85 and 93, opening valves 78 and 90 and by positioning the rotary valve 69 to discharge through the valve 90.and pipe 97, a circulating system is provided for the pump.

In order to set the hoist drum 32 in operation, the brakes 43 and 59 are released and the clutches 38 and 39 actuated to the closed position. Discharge of the pump 66 is then restricted by moving the rotary valve 69 to close the port communicating with valve 90 and pipei 97, which as described hereinbefore causes the planetary element 56 vwhich drives the drum 32 to revolve and actuate the pump plunger 6 to the top of its stroke. WhenA the pump plunger 6 reaches the top of the upward stroke the oscillator 71 actuatesl the rotary valve 69 to permit the pump 66 to disch-arge through the circulating system as described herein-before and the planetary element 56automatically reverses to permit the downward strokeof the plunger 6.

The descending speed of the -plunger 6 is also controlled in this instance by regulating the discharge of the pump 66 by means o the valve 90.

The operation of the system continues in this manner until the fluid which is being raised from the well reaches the surface as evidenced by discharge through the vent valve 31, in which case the intake ort of the pump 66 is connected to the casing cap 21 by opening the valves 23 and 8l. Since the iuid in the storage tank 95 is no longer required for controlling the operation of the pump-66, the valve 96is closed, and therefore the fluid from the well is pumped directly into the storage tank 95.

It will be readily understood that the operation and control of the pump l66 will be the same as described hereinbefore, the pump now receiving fluid from the well instead of from the tank 95 and dischargin under control of the rotary valve 69 into t e storage tank 95 or into any other suitable receptacle, such as storage tank 89 as by opening valve 93. Furthermore, opening

valves

27 and 92 will permit the well fluid to ilow through tubing cap 26 into tank 89.

It will be readily understood that the system as shown may be utilized at any time to perform hoisting operations, such for example as removing the rods or tubing from the well, by using the fluid in the tank 95 for controlling the operation ofthe pump 66 as'hereinbefore described in detail. However, in this instance the discharge of the pump 66 is controlled by positioning the rotary valve 69 to discharge through the valve 90 and pipe 97, with the oscillator 71 disconnected from the drum 32, and then alternately opening and closing the valve 90 to obtain lowering and hoisting operation of the drum 32.

It will be apparent that in operating the system as set forth hereinbefore, the kinetic energy of the descending pump string comprising the rods 8 and plunger 6, will be transmitted through the reduction gear mechanism 35 to the motor 61, as well as to the work device 66. This will tend to overspeed the motor 61 thereby providing a regenerative braking action which will limit the motor speed and return electrical energy to the power circuit.

From the foregoing explanation it will be apparent that a pumping system is provided wherein an ordinary plunger pump such as is commonly used for pumping oil wells and the like, is operated in accordance with the best practice, by utilizing an auxiliary work device for controlling the operation of the pump and in addition for doing useful work such for example as tpumping fluid or compressing gas or air or various uses. Since the principle of the invention is such as to utilize the ener stored in the moving parts of the pump or operatin the auxil- 1ary work device the eiciency o the system as a whole is high, which is a very deslrable feature.

While the illustrated example constitutes a practical embodiment of my inventionLI do not limit myself to the exact details herein illustrated, since modifications of the system can be made without departin from the spirit of the invention as define in the appended claims.

I claim as my invention:

1. In a well pumping system, the combination of: two concentric well casings, an intermediate coupling for the outer of said casings, said coupling being arranged to receive the lower end of the inner casing and to provide a common fluid chamber for both said casings, a pump disposed in said outer casing below said coupling and actuated by a source of power at the top of the well, and means connected to the upper end of one of said casings for forcing compressed gas through the last named casing into the aforesaid chamber.

2. In a well pumping system the combination of: two concentric well casings packed fluid tight against each other at the top of the Well and having unrestricted fluid communication with each other at the lower end of the inner of said casings, a mechanically Operated pump disposed in the outer casing below the inner casing for lifting the well fiuid in said casings, said pump being operatively connectedgto power driven mechanism at the top yof the well, a motor for operating said mechanism, and means connected to the upper end of "one of said casings forforcing compressed gas through said casings.

3. In a pumping system, in combination, a well casing, mechanically operated pumping means disposed in the casing, pressure pumping means for assisting the mechanica ly operated pumping means in lifting iiuid from the casing, a motor for supplying energy to said pumping means, and intermittently actuated means for jointly controlling the action of the mechanically operated pumping means and the pressure pumping means.

4. In a^pumping system, in combination, a well casing, mechanically operated pumping means disposed in the casing, pressure pumping means for assisting the mechanically operated pumping means in lifting fluid from the casing, a motor for supplying energy to' said pumping means, power transmission means connected between the motor and the mechanically operated pumping means, and means actuated in accordance with the operation of said mechanically operated pumping means for controlling the operation of the power transmission means and the pressure pumping means.

5. In a system for pumping oil from wells in combination, a mechamcally operated pump provided with a plunger, a motor for actuating the pump, a compressor for delivering compressed fluid, means for utilizing the motor for actuating the compressor during a pumping stroke, means for utilizing the pump plunger for operating the compressor on the down stroke, and means for delivering the compressed fluid into the well to cooperate in the pumping operations.

6. In a pumping system, in combination, a well casing, a plunger pump disposed in the casing, a motor for operating the plunger pump, means interposed between the pump and motor, for controlling the operation of the pump, said control means including a hoisting drum for operating the pump and a differential gear mechanism for contr/lling the operation of the hoistin drum, and means operatively connected wlth the differential gear mechanism for compressing and forcing lifting fluids into the well casing, said means being disposed to control the operation of the gear mechanism to effect the operation of the pump.

7. In a pumping system, in combination, a well casing, a plunger pump-disposed in the casing, a motor for operating the plunger pump, means interposed between the pump and motor, for controlling the operation of the pump, said control means including a hoisting drum for operating the pump and a dierential gear mechanism for controlling the operation of the hoisting drum, a compressor connected in the pumping system for forcing compressed lifting fluid into the well casing and means disposed to control the discharge of said compressor and thereby effect the operation of the dierential gear mechanism for actuating the plunger pump.

8. In a pumping system, in combination, a Well casing, a plunger pump disposed in the casing, a motor for operating the plunger pump, means interposed between the pump and motor, for controlling the operation of the pump, said control means including a hoisting drum for operating the pump and a differential gear mechanism for controlling the opera-tion of the hoisting drum, a compressor connected in the pumping system for forcing compressed lifting fluid into the Well casing and means actuated in accordance with the rotating of the hoisting drum disposed to vary the discharge of the compressoi` thereby varyino' its load to effect the operation of the diqbrential gear mechanism for actuating the plun er pump.

In testimony whereo I have hereunto subscribed my name this 21st day of February,

FREDERo W. HILD.