US2057859A - Swab - Google Patents

Description

Patented Oct. 20, 1936 PATENT OFFIQE SWAB Fer A. Thaheld, Dallas, Tex., assgnor to C. S. Crickmer, Dallas, Tex.

Application November 2, 1934, Serial No. 751,159

9 Claims.

This invention relates to a swab.

An object of the invention is to provide a swab particularly designedfor use in wells such as oil wells and which is equipped with a novel type of packing element or sleeve.

Another object of the invention is to provide, in a swab, a novel type of reinforced packing sleeve.

Another object of the invention is to provide in a swab a novel type of packing sleeve wherein means are provided for limiting the expansion of the sleeve under the load so that the sleeve will not be expanded into the annular spaces between adjacent sections of the well tubing, and thereby injured as the load is being lifted.

A still further object of the invention is to provide a swab wherein the packing sleeve is of such novel construction and mounted in such novel manner that it will at all times form a comparatively tight t with the surrounding pipe upon upstroke, but will readily relax upon down-stroke so that there will be no substantial wear on the packing on down-stroke of the swab; furthermore, the swab is so mounted that the lower end portion of the packing sleeve will initially take the major portion of the wear and the sleeve will consequently be gradually worn from beneath, upwardly, to the end that a close fit will at all times be formed between the sleeve and the surrounding pipe upon upstroke of the swab until the sleeve is entirely worn out.

In the completion of an oil well, after the producing stratum has been reached and the flowpipe, usually including a screen, has been set in the well, the heavy drilling fluid should be removed from the well in order to remove its pressure from the producing stratum, and the swab is used for this purpose; or sometimes water is forced down through the flow-pipe through the screen and returned up on the outside of the fiow-pipe or tubing and thereafter the water remaining in the flow-pipe or tubing must be removed, necessitating the use of a swab; or sometimes the swab is used to create a vacuum' or partial vacuum in the well to induce the flow of oil from the stratum into the flow-pipe. The particular type of swab herein described is useful for either or all the above and other purposes.

With the above and other objects in View, the invention has particular relation to certain novel features of construction, operation, and arrangement of parts, an example of which is given in this specification and illustrated in the accompanying drawing, wherein:-

Figure 1 shows a side view of the swab partly in section as used in the Well.

Figure 2 shows an enlarged fragmentary vertical sectional view.

Figure 3 shows a fragmentary side elevation partly in section of a modified form of the packing sleeve.

Figure 4 shows a fragmentary vertical sectional view of still another form of said sleeve, and

Figure 5 shows a cross-sectional view taken on the line 5 5 of Figure 2.

Referring now more particularly to the drawing wherein like numerals of reference designate the same parts in each of the figures:-

The numeral I designates the tubular supporting body for the packing sleeve, attached to the lower end of which is the guide nipple 2, which is of tubular formation and has also the side outlets 3. On the body above the guide nipple 2 there is a ferrule 4 which is preferably fixed to said body.

Around the body there is a packing sleeve 5 Whose lower end is tapered and fitted into the upwardly flared portion 6 of the ferrule.

On the upper portion of the body there is a ferrule 'I whose lower portion is downwardly flared, as at 8, and the upper end of the packing sleeve 5 is tapered and fitted into the ferrule l. It is to be noted that the ferrule 'I is slidable on the body, and it is to be further noted that the packing sleeve may be fitted rather loosely on said body. The packing sleeve has reinforcing rings, as 9, embedded therein on the inside thereof. As shown in Figure 1, these rings are formed with wide bases I0 at their inner sides, said rings being preferably formed of relatively thin material folded together with the edges turned outwardly in opposite directions to form the wide bases I Il. In Figures 3 and 4, modified forms of the packing sleeve, as 5a and 5b are shown having the reinforcing 9a, 9b. The inside of the sleeve 5a is reinforced by a bellows-shaped reinforcement 9a preferably formed of metal and the reinforcement 9b may be formed of a spiral strip of metal embedded in the material of the packing sleeve. The reinforcements 9 and 9b may be provided with the holes II, and IIa respectively, so that the material of the packing 5, 5b, may be moulded therethrough to anchor said reinforcements in place. The packing sleeve may be formed of resilient material such as rubber or the like having the necessary expansive qualities, and the reinforcement 9b may have a base 9c extending out each way therefrom, as shown also in Figure 4.

Attached to the upper end of the body I above the ferrule l, there is a valve cage I2 having a suitable inside seat I3 controlled by the upwardly opening ball valve I4, said cage having the necessary side outlets I5.

A sucker rod I6 may be connected with the upper end of said cage through which the swab may be lowered into and Withdrawn from the Well; or a wire line may be attached to the cage I2 by means of a suitable socket and said line may be used for manipulating the swab.

In use the swab may be lowered into the well containing liquid, and while being lowered, the packing sleeve will be relaxed so that it will not be in close frictional engagement with the well tube I l. As the swab is lowered through the liquid, the valve I4 will open, and when the vswab has reached the desired depth in the liquid, said swab may be pulled upwardly and the valve I4 will close so as to trap the load above. The weight of the load of liquid will cause the ferrule 1 to move downwardly on the body and will expand the packing sleeve into close contact with"4 the tubing I1, and the swab may then be ele-gA vated to the top of the well to discharge the ientrapped load above and the process may be repeated until; the well is relieved of the liquid therein so that the pressure of said liquid vmay be removed-from the stratum supposed to contain oil. The swabbing process may be conducted, if desired, vacuum in the well beneath the swab so as toY encourage the inflow of oil into the tubing from `the surrounding stratum opposite the screen.` The bases l0 will come into contact* upon expansion of the rubber packing sleeve 5,-

so as to limit the expansion of the packer and the bellows 9a will limit the expansion of the packer 5a, so thatthe material between the reinforcement willnot be disrupted, and so that the material thereof will not be forced out` into the spaces between adjacent sections ofthev tube i1, which are connected by the couplings I8, as

shown in Figure 1, and thereby injured.

It has been found in practice thatthe lower portion of the packingv sleeve will sustain the greatest amount of `friction against the tubing so that the packing sleevewill be worn upwardly from beneath but the packing will continue to form a close t with the tubing, upon upstrcke, until the sleeve is practically worn out throughout its length. This is true particularly due to i the shape and arrangement of the reinforcing rings. a downward pressure on the swab and since the lower ferrule l is immovably mounted on the body l, and the lower ring 9 is adjacent the upper end of said ferrule, the rubber beneath the said ring-,in the ferrule cannot expand and `said lower ring will be held stationary. Under these conditions the concentration of the load will be between the lower ring andthe next succeeding ring above causing the rubber between thesetwoA rings to be `forced transversely against the pipe H. When this portion of the rubber sleeve has become worn out and the bases of the two rings referred to contact, then the second ring from the bottom becomes stationary. and the load is transferred tothe rubber of the sleeve 5 between the second and third rings from the bottom, and this procedure is repeated from below upwardly until the sleeve is worn out, at which time the bases of the adjacent rings will contact.

The drawing and description disclose what is now considered to be a preferred' form of the invention by way of illustration only whilerthe broad principle of the invention will be definedA by the appended claims.

What I claim is:

l. In a swab shaped to be loweredinto. a well tubing and having a tubularbody; an expansible packing sleeve shaped to t overthebody, rneansfr on the body supporting the lower end of the sleeve,-the upper end yof the vsleeve being freeto allowfthetsleeve to be-compressedA end-wiseiby to create a vacuum or partialv The load of fluid above the swab exerts v the weight of the liquid in the tube above, upon upward movement of the swab, whereby the sleeve will be expanded transversely into contact with the tubing and longitudinally spacedreinforcing means -within the sleeve and widened longitudinally adjacent the body.

2. A tubular packing sleeve having approximately rigid reinforcing means therein, said reinforcing means having widened portions adaptterial, said sleeve being expansible upon the ap-1 plication of end-wise pressure thereto, said reinforcing means having widened bases around their inner sides and thusA being shaped to limit the range of such expansion.y

4. In a swab shaped to be lowered into a Well tubing andhaving a tubular body; an expansible packing sleeve shaped to fit over the body, and having itsupper and lower ends tapered to ilt into correspondingly 4shaped ferrules, annular reinforcingmeans embedded within, 4the sleeve, and having their inner sides widened.

5. A tubular packing sleeve having annular, rigid reinforcing meansl therein spaced apart, said sleeve being expansible upon the application of endwise pressure thereto, said reinforcing means-.having widened portions adapted to contact, upon expansion of the sleeve, to limit the range of such expansion. Y

6. In a swab, a tubular packing sleeve formed of resilient-material and shapedto be fitted over a cylindrical supporting member, annular reinforcing means Aembedded in thematerial of the sleeve and spaced apart and shaped to closely surround said member, said'reinforcing means being formed of approximately rigid material and having widened bases arranged to t around the lsupport on which the sleeve is mounted.

7. A tubular packing sleeve formed cf resilientv material, end ferrules fitted over the ends .of the sleeve and formed of rigid material, an-

Ainner margins of the reinforcing means being provided with wide bases.y

8. In a swab, a tubular packing sleeve formed therein formed of substantially rigid material and-arrangedalong the sleeve longitudinally, said reinforcing means-having extended stops directed longitudinally on the sleeve and positioned t0 contact. upon the application of endwise compressive force to the sleeve to limit the endwise compression of thesleeve. v

9.1In a swab, an eXpansible tubular packing sleevev formed of resilient material, approximately rigid reinforcing ,means embeddedtherein and arranged longitudinally therealong, said reinforcing""rneans having widenedV portions" which w formstopsa'nd which are sopositioned thatthey may contact with each other luporrapplication of endwise-'compressive force tothe sleeve to thus ,limitthe expansion o f the sleeve.'

PERI A. ,'-rHAHELn 'of resilient packing material, reinforcing means

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