US2151588A - Pumping apparatus - Google Patents

Description

March 21, 1939. s. A. EMERSON PUMPING APPARATUS Filed June 28, 1937 ,f l IIII.

Patented Mar. 21, 1939 UNITED STATES PATENT GFFICE PUMPING APPARATUS tion of Louisiana Application June 28, 1937, Serial No. 150,873

2 Claims.

This invention relates to improvement in oil well pumping apparatus.

When a wellceases to flow under its own power, it is necessary to provide means for raising the oil to the surface of the ground. The conventional apparatus for raising the oil consists of an o'il well tubing to which is attached a working barrel, a standing valve being located at the bottom of the working barrel. A travelling valve is caused to reciprocate within the working barrel by sucker rods. The travelling valve is provided with a plurality of upwardly turned leather packing cupswhich operate under extremely adverse working conditions.

Due to the severe conditions under which the pumping apparatus operates in a deep well, it is frequently necessary that the travelling valve be withdrawn and the packing cups replaced. The frequency with which the packing cups have to be replaced isv dependent to a certain extent upon variations in working conditions. Moreover, due to wear it is necessary at times to replace the working barrel of the vpumping apparatus.

To replace the packing cups it is necessary that the sucker rods be pulled and this may be done in a comparatively short period of time. To replace the working barrel requires the withdrawal of the oil well tubing and takes a considerably longer period of time. Such replacements naturally result in the temporary shutting down ofthe production of the oil well,v and it is highly desirable that the necessity for replacements be reduced as much as possible.

Quite frequently, due to the breaking of the` sucker rods or to a loose connection therein, it is necessary to partially withdraw the travelling valve from the working barrel in order that the defect may be remedied. Such withdrawal has heretofore usually resulted in the edges of the leather packing cups being turned downwardly as soon as the plunger has passed the upper end of the barrel, thus necessitating the complete withdrawal of the sucker rods in order that the cups may be replaced although they may have had comparatively little wear. As a matter of fact, the cups are turned downwardly so frequently that it `has become the practice to assume that this result will occur whenever the plunger is pulled upwardly from the barrel. Accordingly, an operator will completely withdraw the sucker rods and plunger from the well whenever the necessity arises for any repair which requires the elevation of the plunger above its normal working stroke.

(Cl. 10S-179) Moreover, when the conventional plunger is pulled upwardly above the working barrel and the packing cups are turned inside out as stated above, it frequently occurs that pieces of the leather of the packing cup will break off and find their way to the bottom of the working barrel where they will interfere with the seating of the standing valve. Accordingly, it is sometimes necessary to withdraw the working barrel from the well in order that pieces of leather from the packing cups may be removed from the standing valve.

This invention has for its object the provision of means whereby the number of times which it is necessary t0 withdraw the travelling valve or tubing and working barrel due to causes other than normal wear may be reduced.

A further object is to provide means whereby the pressure of fluid on each side of the travelling valve at the time of withdrawal thereof from the working barrel is equalized, thus preventing the packing cups from being turned downwardly.

A further object is to provide a by-pass having its ends spaced apart a distance greater than the length of the plunger and adapted to equalize pressure at opposite ends thereof when the plunger is raised to a position above its normal upper limit of movement, thereby preventing the cups from being turned inside out upon the raising of the plunger and permitting the making of numerous repairs without removing the plunger from the well.

Other objects and advantages of the invention will become apparent from the following description.

In the drawing I have shown one .embodiment of the invention. In this showing:

Figure 1 is a side elevation of the preferred embodiment of this invention installed in a well, parts being shown in cross-section and parts being broken away,

Figure 2 is an enlarged sectional View showing the working barrel, travelling valve, and standing valve, parts being shown in elevation and parts being broken away,

Figure 3 is a sectional view of the working barrel taken on line 3--3 of Figure 2, and

Figure 4 shows a variation by which this invention may be adapted to the conventional working barrel.

In the drawing, the numeral l0 indicates the main casing of an oil well having an inner tubing II to which is attached the working barrel I2 by means of a cylindrical coupling I3. A conventional standing valve I4 is located at the bottom of the barrel and is attached to the working barrel by means of a coupling I5. Within the working barrel is arranged a conventional travelling valve I6 connected to the lower end of a string of sucker rods I'I to be reciprocated thereby.

A conventional plunger is connected to the body of the travelling valve and includes a plurality of leather packing cups I 8. The packing cups have upturned flanges I9 as shown in crosssection in Figure 2 and are secured to the body of the travelling valve by means of internally threaded annular rings 20 which engage with an externally threaded hollow member 2I, secured to the body of the travelling valve I6 by means of a coupling 22.

Ihe working barrel I2 is provided with a plurality of grooves 23, as shown in Figures 2 and 3. The travelling valve reciprocates within normal upper and lower limits of travel in the-normal operation thereof, and the grooves 23 are located above the normal upper limit of travel of the plunger. It has been found sufcient to make the grooves 23 one-fourth the total length of the Working barrel, although the length of these grooves 23 may be varied Within reasonable limits, so long as the grooves are longer than the plunger, for a reason which will become apparent.

In. a conventional pumping apparatus, it is customary to employ a working barrel of smaller diameter than the corresponding diameter of the tubing to which the barrel is connected. This difference in the diameter of the parts referred to permits the travelling valve and plunger to be freely withdrawn from the well after having been moved upwardly out of the working barrel. In such construction, the working barrel is connected to the inner well tubing by means of a coupling having two sets of threads, the upper of which is threaded on the lower end of the well tubing and the lower of Which is threaded on the upper end of the Working barrel. Because of the size of the coupling and the material from which it is made, the coupling is substantially more expensive than an ordinary cylindrical coupling, such as the coupling I3 previously described.

However, such aY coupling may be employed where it is desired to utilize a conventional working barrel in conjunction with the present invention. For example, a conventional working barrel may be employed in the manner shown in Figure 4. The working barrel is indicated by the numeral 24 and the upper end of such barrel is threaded into a coupling 25 which may be identical with the coupling usually employed for connecting the upper end of the working barrel with the lower end of the conventional inner well casing.

'I'he upper end of the coupling 25, instead of being directly connected to the lower end of the tubing I I, is threaded on the lower end of a sleeve 26 which has an internal diameter corresponding to that of the barrel 24, and an external diameter corresponding t0 that ofthe tubing II. Accordlngly, the upper end of the sleeve 26 may be connected to the lower end of the tubing II by a cylindrical coupling 2'I, similar to the coupling I3 previously described. The inner surface of the sleeve 26 is provided with longitudinal grooves 28 for the same purpose as the grooves 23, previously described, as will become apparent.

Although the invention may be adapted to the standard working barrel by means of the connection 26 as shown in Figure 4, Ythe preferred construction is shown in Figure 2. In the preferred construction the internal diameter of the working barrel I2 is smaller than the internal diameter of the tubing II, the external diameters being the same. Although this results in the necessity of using heavier stock to make the working barrel I2, any increase in cost is compensated for by the elimination of the additional parts shown in Figure 4. Moreover, the heavier working barrel I2 can be made as cheaply as the combined cost of the conventional barrel 24 and sleeve 26 due to the elimination of the comparatively expensive coupling 25 which is necessary when using the conventional working barrel 24.

In the normal operation of the apparatus the traveling valve I6 operates between upper and lower limits of travel, these liimts being dependent upon the stroke of the pumping apparatus (not shown). On the up-stroke, the standing valve I4 will be opened and fluid will be drawn into the Working barrel and the traveling valve I6 will be closed. The travelling valve I6 being closed on the up-stroke, the fluid above the travelling valve will be lifted. Inasmuch as there is frequently a head of several thousand feet above the travelling valve it is readily apparent that there will be extremely large pressures forcing the packing cups into contact with the working barrel I 2 thus preventing any of the uid from passing by the packing cups I8. On the down stroke of the plunger, the travelling valve I6 will be opened and the standing valve I4 will be closed, the oil which entered the working barrel on the up-stroke flowing through the travelling valve I6 preparatory to being raised in the well known manner.

On the up-stroke of the travelling valve I6, it is readily apparent that there will be an extremely high pressure on the upper side of the travelling valve While on the lower side of such valve there will be a vacuum tending to draw oil into the working barrel I2. Quite frequently the oil will not enter the working barrel as fast as the travelling valve is being raised. Thus on removing the travelling valve from the conventional working barrel 24 into the larger diameter of the tubing II, it is obvious that the pressure of the liquid above the plunger Will force the liquid past the plunger into the Working barrel. Heretofore this has resulted in the up-turned portions I9 of the packing cups I8 being turned downwardly or inside out, due to the rush of fluid by said packing cups I8. Such action renders the cups I8 unt for further use and necessitates the complete removal of the travelling valve in order that said cups may be replaced.

Moreover portions of the leather will quite frequently break off and enter the working barrel where they will interfere with the seating of the standing valve I4, thus necessitating the more expensive and troublesome removal of the tubing II together with the working barrel i2 in order that such pieces of leather may be removed from the standing valve.

By providing the upper portion of the working barrel with the grooves 23 it has been found that the tendency of the leather packing cups to turn over has been eliminated. It will be apparent that when the packing cups I8 are opposite the grooves 23, liquid will be free to ilow downwardly into the working barrel, thus equalizing the pressure of the oil above and below the travelling valve. This equalization in pressure takes place during the travel of the cups I8 past the groove portions 23. The cups I8 are prevented from turning over during this period of pressure equalization due to the restraining influence of those portions of the working barrel between the grooves 23. Thus pressures are equalized above and below the valve beforc'withdrawal of the travelling valve from the Working barrel, and it is readily apparent that when the travelling valve enters the tubing ll there will be no change in conditions which will cause the 11p-,turned portions of the packing cups. to turn downwardly The cups remaining in their normal position, it will be possible to withdraw the travelling valve to make repairs to the sucker rods without necessitating their complete removal for the purpose of replacing the packing cups or the removal of the tubing to remove portions of the packing cups from the standing valve.

As previously stated, the packing cups are turned inside out so frequently in normal constructions that it has become the practice to assume that this result will occur Whenever the plunger is pulled upwardly from the barrel. Whenever it is necessary to Withdraw the plunger from the barrel, therefore, operators assume that the cups have turned inside out, and accordingly it has become the practice to completely remove the sucker rods and the parts carried thereby whenever it becomes necessary to elevate the plunger a sufiicient distance to cause it to leave the working barrel. The present invention, therefore, permits the making of numerous repairs without the necessity of removing the travelling barrel and plunger, thus effecting a substantial saving in time and labor.

lt will be apparent that the forms of the invention shown in Figures 2 and 4 operate in identically the same manner, it being immaterial from the standpoint of operation Whether a unitary structure such as the member l2 is employed to form the Working barrel and to carry the grooves or passages 23, or whether the structure referred to is made in separate pieces, as in the working barrel 24 and sleeve 26 of Figure 4. Therefore, where the expression working barrel is employed in the claims, it is understood that this expression is intended to cover the unitary construction of Figure 2 or a combination of the barrel 24 and sleeve 2B in Figure 4.

It is to be understood that the forms of my invention herewith shown and described are to be taken as preferred examples of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

l. In a iluid pumping apparatus, a working barrel, and a plunger reciprocable in Said barrel within fixed limits of travel and comprising a plurality of packing cups having upstanding annular flanges, said barrel being provided with a longitudinal groove in the internal surface thereof extending from the outlet extremity of the barrel to a point spaced therefrom a distance at least as great as the length of said plunger.

2. In a pumping apparatus, a vertical working barrel having a cylindrical bore, and a plunger mounted to vertically reciprocate in said barrel between predetermined limits of travel with the upper limit of travel of the upper end of the plunger terminating a substantial distance below the upper end of said bore, said plunger comprising a plurality of flexible cups having upturned angular flanges engaging said bore, said barrel being provided with a groove cut in said bore from the upper extremity thereof downwardly to a point spaced from the upper extremity of the bore a distance greater than the distance between the upper end of the uppermost cup and the lower end of the lowermost cup.

SLOAN A. EMERSON.

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