US2304372A

US2304372A - Pump plunger

Info

Publication number: US2304372A
Application number: US345563A
Authority: US
Inventors: Walter A O'bannon
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-07-15
Filing date: 1940-07-15
Publication date: 1942-12-08
Anticipated expiration: 1959-12-08

Description

Dec. 8, 1942- w.-A. OBANNON PUMP PLUNGER v2 0 1 m v a a m 0 H 2 NO -R 2 E o s v an T t 6 m, T. e 8 A 2v W I B m 9 W L3 5 l V m J 1 w l i wlmu 3 7 m mm 5 Patented Doc. 8, 1942 PUMP PLUNGER Walter A. OBannon, Tulsa, Okla.

Application July 15, 1940 Serial No. 345,583

8 Claims.

This invention relates to pumps for oil andsimilar fluid producing wells, and more particularly to a plunger ior such pumps.

Pumps this character include a working barrel reciprocated over a fixed plunger, or a plunger reciprocable within a fixed barrel, to draw in a fluid charge upon upstroke of the movable member and to transfer the fluid charge into the well tubing upon the downstrdke, which charge is displaced subsequently to the succeeding upstroke. Due to the abrasive matter usually contained in the fluid and the difliculty of maintaining a seal by rings, the primary seal between the stationary and working members is largely through an extended working surface therebetween brought about by making the members of relatively long length. However,it is necessary to provide a certain operating clearance between the working parts, with the result that the well fluid works therebetween by reason of the vacuum effected within the barrel upon upstroke of the movable member. This in itself is not objectionable as the fluid tends to make a seal, but the well fluids usually contain a considerable amount of salt water or other fluid having electrolytic properties, with the result that electrolysis occurs between the pump members, causing their rapid deterioration. This is especially aggravated in the case of working barrel pumps because the salt water, being of heavier specific gravity, setties into the space between the tubing and the working barrel and is trapped therein, so that the invention, as hereinafter pointed out, I have provided improved details-oi structure, the preierred form ot'which is illustrated in the accompanying drawings, wherein:

Fig. l is a vertical section through a well tubing containing a pump constructed in accordance with the present invention, the working barrel.

and valve cages being'shown in section- Fig. 2 is an enlarged vertical section through the pump plunger.

Fig. 3 is a cross-section on the line l-I of Fig. 2.

Fig. 4 is a longitudinal section through a modifled form or pump plunger which embodies features oi the present invention.

Fig. 5 is a cross-section on the line 5-5 of I designates a welltubing that extends from a point below the level 01 fluid collecting in the well to the top thereof, and forming a duct the working barrel is being constantly reciprowhich the plunger is constructed. In any event,

the metal parts become pitted and the reciprocatory action hastens their destruction.

It is, therefore, a principal object of the present invention to provide a plunger construction which obviates this difliculty so that a pump may be operated in such fluids for longer periods of time and thereby reduce replacement costs, as well as delays and inconvenience incidental to removal and replacement of the pump.

A -iurther object 01 the invention is to provide a pump plunger construction which makes a more eflective seal with the barrel so as to retard leakage of fluid and particularly that portion thereof producing the electrolytic action.

In accomplishing these and other objects of through which the fluid is lifted responsive to operation of a pump 2.

In the illustrated instance, the :pump 2 includes a stationary plunger 3 and a reciprocatory barrel 4, movable over the plunger responsive to actuation of a pump unit having connection with the barrel by sucker rods 4'. The plunger 3 includes an anchor or hold-down i wedgingly seated in the tapering bore 6 01' a shoe 1 carried by the well tubing.

Extending upwardly from the anchor I is a plunger tube 8 including a lower section 0 suitably connected with the anchor 5 as at 8' and having its upper end adapted to be connected with the threaded lower end It of an upper section II which carries the plunger body elements having contact with the inner surface of the barrel 4, as later described. The upper end of the section H is threaded, as at II, to mount a valve seat fitting II carrying a valve ll.

The barrel 4 is reciprocable in coaxial relation over the plunger, and is of sufllcient length to accommodate the length 01' the plunger plus the desired maximum working stroke of the pump.

The upper end of the barrel carries the usual working valve l5, which cooperates with the valve ll in controlling movement 01 the fluid responsive to reciprocation oi the sucker rods.

On the upstroke of the working barrel, the

- is passed-from the top of the well.

standing valve i4 unseats and a fluid charge is drawn into the space [6 between the upwardly moving working valve 15 and the valve I4. n 1

the downstroke this fluid is trapped by the closed of heavier specific gravity than the oil and settle into'the space I I between the working barrel and well tubing. Upon the upstroke, a vacuum is Q drawn-in the upper end 0i the working barrel, 4 which, supplemented by hydrostatic head oi well flu'id in the tubing, causes the solution to work its way upwardly between the working barrelarid plunger.

result that the generatedcurrent causes elec-' and subject to rapid wear.

In order to overcomethls diflEiculty, I have pro-'- vided a plunger construction so designed that electrolytic action is resisted between'the working barrel and plunger or the component parts thereof, as now to be described. Sleeved upon the up per tubular section is a series of sleeve-like sections I8, each having an outer circumference to be snugly slidable within the barrel to reduce as much as possible the clearance therebetween. The sleeve-like sections .may be formed of metal,

in which instance they are spaced fromthe tube H by a softer metal 19, higher in the electrochemical series .than the metalcomposing the barrel 4, the tube H, or the sleeve-like sections II. The ends of the sections are also spaced I apart by rings of the same or similarsoft metal, so that the sections composing the plunger are entirely separated from each other by such metal. The sections are retained in'-abuttin contact with the separating rings and from shift-' ins movement on the tube-like body H bya nut 2|, which cooperates with the seat fitting ill. Similar washers 2'2 and 23 are inserted between the endmost sections and the retaining members l2 and 2|, as clearly shown in Fig. 2. The sleevef like sections may be provided with annular grooves 24 extending circumfe'rentially thereof to form oil seals with the inner. surface of the working barrel.

With this construction, any electrochemical action taking place between the parts of the plunger will be resisted by the inserted metal.

Any electrolytic action whichdoes occur results in decomposition of the softer material rather than the working surfaces of the sleeve-like sections and forms a dielectric as a primary product of corrosion incidental to said decomposition and resists galvanic action responsive to metal contact. Therefore, the sleeve-like sections retain their original properties and maintain the'desired seal with the inner surface of the working barrel.

Ihavealso foundthat thesleeve-like sections may be formedof dielectric composition such as one of the synthetic resins; in which case the sleeve-like sections 25 (Fig. 4) are sleeved directly on the tube-like. body of the plunger and retained in end to end engagement with oil seal rings inserted therebteween, indicated at 26. These rings may include flexible cups 21, having inwardly extending annular flange portions 28 clamped between

spacers

29 and 30, whereby sealing lips ti ofthe rings are retained in position to maintain seal with the inner surface of the working barrel.

. The plunger is, therefore, continuously C operating within an electrolytic solution, with the trolysis of the metal parts, leaving them pitted trolysis are not considered.

. Patent is:-

1. Acomposite pump plunger for pumps han- The spacers 28' are preferably recessed, as at 32. so as to allow the necessary movement of the sealing lips.

In Fig. 6 the tube-like body of the plunger is covered with the outer sleeve 33 formed of dielectric or insulating material. This sleeve may be coextensive with the length of the plunger body or formed in sections which are retained in abutting contact with eachother. With some of the more brittle dielectric materials, it may bedesirable to form the dielectric material directly upon 'a metallic sleeve somewhat similar to the structure used in the form of the invention illustrated in Fig. 2. The dielectric sleeves may be sized to flt closely within the working barrel so as to reduce leakage and provide a long wearing surface which is less abraded by the fluid incidental to reciprocation of the barrel. The sleeve being made of dielectric material, there is no electrolytical action which can take place between the sleeve-like sections and the tubularbody oi the plunger or the working surface of the barrel.

From the foregoing it is obvious that I have provided a plunger construction which is not subject to rapid deterioration incidental to electrolytic action caused by the presence of an electrolytic solution in the well fluid. Consequently, a pump equipped with such a plunger will operate eiflciently for long periods of time, and shutdowns for repairs will be less frequent than in former constructions where the affects ofelec- What I claim and desire to secure by Letters "dlin g fluids having electrolytic characteristics,

said plunger being formed of'inetal parts subject to electrochemical decomposition when operating in said fluids. said parts having facing surfaces and metallic spacing means having-opposite faces respectively contacting the facing surfaces of said metal parts of said plunger and having a property relative to the electrochemical properties of the plunger parts to be the metal affected by electrolytic action.

2. A pump: plunger including, a body member,

a sleeve-like member on said body member, said body n ember and sleeve-like member normally being subject .to electrochemical decomposition when used in connection with fluids having electrolytic characteristics, and a metallic insert between said sleeve-like member and body member having a property relative to the electrochemical properties of the sleeve-like member and body said sleeve-like sections, said inserts being formed of a metal having a property relative to the electrochemical properties of the sleeve-like sections of being the metal affected by electrolytic action.

4. A pump plunger for operating in fluids having electrolytic characteristics including. a body member and a sleeve member on the body memher, and a readily decomposable metal between the body and sleeve member to form a dielectric member between the body and sleeve members as a primary product of corrosion when the carried on one 0! said members having the propcity of being corroded responsive to metal contact with said member whereby said corrosion forms a dielectric on said member to resist decomposition of said members when subject to electrolytic action.

6. In a pump, cylinder and plunger members formed or metal and one movable with respect to the other, a sleeve member having fixed mountingon one member and slidable engage-1 *ment with the othermember, andmeans intere posed between said sleeve member and the mem her on which said sleeve member is fixed for resisting deterioration of said members by galvanic action responsive to metal to metal contact of said members, said means having a property relative to that of the contacting members of bein I the one subject to decomposition by any galvanic action which tends to occur between said members. 7.111 a pump, a cylinder, a plunger body meming on said body member and sliding engasement with the cylinder member responsive to said movement, and means interposed between said sleeve-like sections and the body member tor resisting deterioration 01' said sections to galvanic action responsive to the metal to metal contact oi said sleeve-like sections with the clllnder and pllmgerbody member, said means having a property relative to that o! the contacting members of ,being'the one subiect'to decompo'-. sition by any eal'yanlc action'which tends to I occur between said members;

'8. In apump, acylinder, a plunger body member in the cylinder, said cylinder and plunger body memberhaving relative movement, a plu-,

ralityof sleeve-like sections having fixed mount- Jingon-s'aid body member and sliding engagement with the fcylinder member responsive to said movement, and spacing means interposed between said sleeve-like sections and the body member and between adjacent ends of said sections for resisting deterioration of said members by galvamc action responsive-to the metal to metal v,

. contact, said means having a property relative action which her in the cylinder, said'cylinder and plunger body member having relative movement, a pinrality o! sleeve-like sections having fixed mountto that or the sections and cylinder of being the one subject to decomposition by any galvanic 'WALTER A. O'BANNON.

tends to occur between said