US1021600A

US1021600A - Swab.

Info

Publication number: US1021600A
Application number: US54060210A
Authority: US
Inventors: Charles M Heeter
Original assignee: Individual
Current assignee: Individual
Priority date: 1910-01-28
Filing date: 1910-01-28
Publication date: 1912-03-26
Anticipated expiration: 1929-03-26

Description

lantea Mar.26,1912.

c. M. HBBTBR. swAB.

APPLICATION FILED JAN. 2K8, 1910. 1,021,600.

F Gal-L WITAN ESS ES, w'fw CHARLESM. HEETER, BUTLER, PENNSYLVANIA.

SWAB.

Specification of Letters Patent.

Patented Mar. 26, 1912.

Application filed January 28, 1910. Serial No. 540,602.

To all 'whom it 'may concern:

Be it known that I, CHARLES M. HEETER, a resident of Butler, in the county of Butler and State of Pennsylvania, have invented certain new and useful Improvements in Swabs, of which the following is a specification. F

Swabs as now constructed for lifting water or oil from oil, gas and other deep wells are constructed with a single onesection rubber sleeve which wears rapidly and must vbe frequently renewed, the greatest wear being at and adjacent the lower end of the sleeve.

One purpose of this 'invention is to protect this part of the sleeve to such an extent as to materially reduce the wear; also to provide for reversing the sleeve and thereby practically double its period of service.

A further purpose of the invention is to increase the efficiency of the sleeve by forming its upper part of softer rubber than the lower part, as I have found that a rubber of this character packs much more effec tively in the casing than one .of uniform resiliency throughout. Furthermore, the efficiency is ,increased by forming the sleeve Iin sections, two such sections being here shown, with the upper section of softer rubber than the lower section, and both preferably so arranged that each may be turned end for end as the lower ends become worn. A further characteristic of the invention is the provision of a yielding top abutment for the sleeve with a spring for opposing upward movement of the abutment and exerting such downward pressure as to aid materially in effectively spreading the rubber within the casing. While the use of this movable top abut-ment and spring are not necessarily confined to a rubber softer at--its upper end than its lower end, nor to-a sleeve formed in sections, the same when used in connection with these features provides a very efficient swab.

An object-ion to swabs as now constructed is that the upwardly opening check ivalve,

vwhich permits upward flow of water or oil asthe swab is lowered and closes when the swab is lifted, is frequently raised from its seat during the upwardmovement by gas under high pressure within the well, and

when thus raised and opened the fluid Hows back through the swab, thereby defeating the very purpose for which the swab is used. This objection is overcome with the present invention by providing valve means of such construction that the greater the pressure from'beneath the more tightly the valve is heldclosed. In the present embodiment, an upwardly closing valve is employed which is arranged in connection with the swab operating stem insuch manner as to'openr during the downward movement and close duringthe upward movement, the whole weight` of the swab being in fact on the valve during such upward movement, and with the arrangement such that any upward gas pressure will tend to increase the seating pressure of the valve.

In the accompanying drawings, Figure 1 isa vertical sectionof a swab yconstructed in accordance with the invention, and Fig. 2 illustrates the improved swab in double form and within a well. f

Referring to the drawings, A designates the tubular stem of the swab which provides an upward vpassage for-water, oil and gas as the .swab is lowered into aA well. Arranged on stem A is the swab rubber B having the ring-like bot-tom abutment .C adjustably secured to the threaded lower portion of the stem and a disk-like -top abutment D movable on the stem, and with a stout spring E embracing the stem between abutment D and the stop-forming head F secured to the upper end of the stem, spring E opposing upward movement of abutment D and exerting downward pressure thereon.

As before stated, a characteristic of the invent-ion is a swab rubber having its upper portion of softer rubber than its lower portion, as thereby a more effec-tive packing within the casing is secured, particularly when. used with a movable spring-held top abutment. In the embodiment here shown, the rubber sleeve is in two sections b and b', with the upper section b `of softer rubber than the lower section. An abutment G may beloosely arranged on stem A intermediate the sleeve sections. 1

The sleeve wears or cuts away more rapidly at and adjacent its lower end, and I have found that when the sleeve is 1n sections, eachsection 1s subject to this wear.

` ButI such wear is materially reduced by so rendering such movement comparativelyI confining the lower end of the rubber as to retard spreading, and this I accomplish by cupping the upper faces of abutments C and (l, as indicated at H, with the extremities of the sleeve sections circumferentially notched or reduced, as at J, to enter the cups. And by notching both ends of each sleeve section, the latter may be reversed and full wear obtained from each, practically double the service secured from the non-reversible rubber now commonly used.

With` the bottom abutment C adjustable, the rubber may be tightened up from time to time as it becomes worn and until no further efiiciency can be secured by contracting it longitudinally. Spring' E coperates with this function of the adjustable bottom abutment, with the result that rthe rubber is at all times maintained in condi tion for effective fitting or packing within the casing. At the same time, the spring permits the rubber to so yield in upward direction during the downward movement of the swab' as to prevent excessive friction,

easy and at the same time relieving the rubber of much wear` which such friction would cause.

It is a common practice in casing wells to use heavier casing for the lower portionof the well than for the' upper portion, the lighter casing being used for say a depth of from 2,000 to 2,500 feet and the heavier casing the remainder of the depth. Both weights of casing are of the same external diameter, but there is usually an eighth of an inch difference in gage between the metals of the two weights, which makes the lighter casing a quarter of an inch larger inside the diameter than the heavier casing.

With the swab rubber arranged between the two fixed abutments as heretofore and of a size to closely fit the lighter casing, the rubber is subjected to great strain and wear when forced into the smaller diameter Yof the lower and heavier casing, and is frequently so torn and mutilated as to be absolutely useless. With the construction here shown, the rubber, while fitting the larger diameter, yields upwardly in such manner as to enter thesmaller casing without injury. The reverse action occurs when the swab emerges from the casing of smaller diameter, the sleeve spreading readily and filling the larger diameter, whereas in the former construction after the rubber has once been forced into the easing of smaller diameter 1t does not pack efficiently in the larger diameter and unavoidable back-flow around the swab results.

As here embodied, a chambered head K is secured to the stop-forming head F with stem A open thereto. A passage L is formed through the thick upper end of head K, and the lower end of this passage is realued to form the valve seat L, with lateral ports or outlets M above the seat. The operating stem N, smaller than 'passage L, extends therethrough and at its lower end carries th'e beveled valve-forming head O which fits seat L and closes head K when the-swab is lifted by means of the operating connection P to which stem N is secured. As the swab is lowered in the casing, stem N and its valve head are in lowered position, as in dotted lines in Fig. 1, thereby providing a free outlet through ports M for the fluid flowing upwardly through stem A, but immediately closing such outlet when the movement is reversed, the position then being as in full lines in Fig. l. With this construction it is obvious that upward pressure of gas through the stem cannot displace the valve, as with the upwardly opening check valve now commonly used, but rather increases the pressure of valve O on its seat, so that such excessivc gas pressure cannot operate as herey tofore to release the fluid being raised.

In wells of great depth, and where very large columns of fluid must be removed, it may be desirable to provide a swab of double construction, as shown in Fig. 2, which is accomplished by using two swabs constructed as above described, omitting the chambered head and valve from the lower swab, and substituting a coupling head F for head F which serves to unite the tubular stems of the two swabs. Obviously, a swab of practically double capacity is thereby secured, i, e., a swab having such casingpacking efficiency as to sustain the enormous weight of a large column of fiuid which might be too great to bc effectively held by a single swab. A further advantage ofn this double construction is that the column of fluid is effectively held when passing an offset formed by the sleeve and wall packer, such as R, Fig. 2. Such a sleeve is usually about three-fourths of an inch larger inside diameter than the casing, and it is clear that a considerable volume will flow back around the swab while the latter is passing through, particularly when the space of larger diameter is longer than the swab. With the double' swab the ywhole length is such that the upper swab will fully Ipass such an offset before the lower swab fully enters the same, 4and no back flow can result.

By the terms rubber sleeve and swab rubber I refer to the full length of the rubber element' irrespective of the sections in which the same is or may -be formed, 'and the claims are to be read with this understanding.

I claim:

1. In a swab, the combination of a tubular stem, a sleeve of compressible rubber conlined on the stem and ycompressed longitudinally by the weight of a column of fluid lifted thereby, the upper portion of the compressible rubber being softer than the lower portion.

2. In a swab, the combination of a tubular stem, a sleeve of longitudinally compressible rubber confined on the stem, the sleeve fully filling the space between the tubular stem and the well casing and compressed longitudinally by the weight ofa column of Huid, the upper portion of the sleeve being of softer rubber than the lower portion.

3. In a swab, the combination of a tubular stem, a rubber sleeve confined on the stem and arranged in sections one above the other, both sections being longitudinally compressible under the weight of a column of fluid with the upper section yielding to greater compression than the lower section.

4. In a swab, the combination of a tubular stem, a longitudinally compressible rubber sleeve confined on the stem, the sleeve arranged in sections one above and closely adjacent to the other, an abutment movable on the tubular stem for the upper end of the sleeve, and 'a coiled' spring encircling the tubular stem and normally exerting downward pressure on said abutment. y

5. A swab rubber of uniform transverse thickness from vend to end with its upper portion softer than its lower portion..

6. A swab rubber having a passage therethrough for atubular stem and of uniform cross-sectional area from end to end with its upper portion of softer rubber than its lower portion. l

7. A swab rubber formed in sections of uniform transverse thickness from end to end with the upper portion softer than the lower portion.

8. In a swab, a tubular stem. a rubber sleeve fitting the stem and of uniformcrosssectional area from end to end, an abutment on the stem for the lower end of the rubber, an abutment movable on the stem for the upper end of the rubber, and acoiled spring encircling the tubular stem and exerting constant downward pressure on the upper abutment.

' 9. In a swab, la tubular stem, a lrubber sleeve thereon having its upper portion formed of softer rubber than its lower portion, and abutments for the upper and lower ends of the sleeve.

vl0. In a swab, a tubular stem, aV rubber sleevethereon formed in sections arranged one above the other with the upper section of softer rubber than the lower section, and

abutments' for the sleeve.

11. In a swab, a tubular stem, a rubber sleeve' thereon formed in sections arranged one above the other with the upper section of softer rubber than the lower section, an abutment between the sections, and abutments for the upper and lower ends of the sleeve. y

1Q. In a swab, a tubular stem, a rubber sleeve thereon formed in sections arranged one above the other, the upper section of softer rubber than the lower section, an abutment secured to the stem forthe lower end of the sleeve, a movable abutment for the upper end of the sleeve, and a spring for opposing upward movement of the upper abutment; y

18. In a swab, a tubular stem, a rubber sleeve on the stem, an abutment secured to the stem for the lower end of the sleeve, a movable abutment for the upper end of the sleeve, a stop device secured tothe stem above the upper'abutment, and a spring coiled around the tubular stem between the stop device and the upper abutment for opposing upward movement of the latter.

,14. A swab having a Huid passage 'therethrough, a chambered head at the upper end of the passage with an opening through the upper end of the head, the head formexi with lateral outlets intersecting saidv opening above the lower end of the latter, an operating stem extending into the head, and a valveforming head at the lower end of the stem closing the top opening when Alifting the swab.

l5. In a swab, the combination of a tubular stem, two swab rubbers arranged on the stem one above the other to formv an elongated swab for the purposey described, an

abutment fixed to the stem for the lower end of the lower rubber, movable abutments for the upper ends of the rubbers, and a spring. for opposing upward'v movement 'ofsaid movable abutments.

16. In a swab, a tubular stem, a rubber sleeve on the stem formed in sections one above the'other, means fixed to the stem and engaged by the lower end of therubber sleeve, and a coiled spring encircling the tubular stem and exerting constant downward pressure on the upper end of the sleeve. y

17. A swab having a fluid passage therethrough, a chambered head at the upper end of the passage with an opening through the upper end of the head, the under side of the upper end of the head forming a valve seat, the chamber having lateral outlets above the valve seat, an operating stem adapted to bear against the upper end of the chambered head andv closing the opening therethrough when lowering the swab inl a well, a valve stem projecting downwardly from the operating stem and through the, top opening in the chagnbered head, and a valve-forming head at the lower end of the valve stem adapted to engage said valve exerts compressing pressure on the lower seat when the operating stem is lifted for rubber. Y 10 elevating the swab. In testimony Whereoj:l I aix my signature 18. In a swab, the combination of a tubuin presence of two Witnesses.

g lar stein, and two longitudinally eornpres- CHARLES' M. HEETER.

sible swab rubbers arranged on the stem one Witnesses: above the other and spaced apart, the space JAMES O. CAMPBELL, between the rubbers reeelving fluid which GRACE E. HARKLESS.