US1563164A

US1563164A - Reenforced swab cup

Info

Publication number: US1563164A
Application number: US4630A
Authority: US
Inventors: Christenson George
Original assignee: Johns Manville Inc
Current assignee: Johns Manville Inc
Priority date: 1925-01-24
Filing date: 1925-01-24
Publication date: 1925-11-24
Anticipated expiration: 1942-11-24

Description

Nav. 24, 1923. 1,563,164

G. cHRlsTl-:NsoN

REENFORCED SWAB CUP Filed Jan. 24, 1925 vit-:ia64 FFICE. 1

PATE-'l GEGRGE GHRISTENSQN, 0F NORTH PLAINIELD, NEW JERSEY, ASSIGNOB 5.50 JOI-INS- MANVILLE, INCORPDRTED, 0F NEW YRK, N. Y., A CORPORATION OF-NEW YGRK.

REENFORCED SWAB CUP.,

.application meer ranuar'y e4, 192%. sei-iai no. asso.,

This invention relates to heavy duty MP plungers, liting-bailers or swabs, so-called,

and particularly applies to devices adapted to make a fluid-tight connection operative under great pressantes between a draft-rod or stem and a mechanically imperfect `interior cylindrical surface, such as is characteristic or!s the tubular casings of deep wells.

lin deep well practice, for instance in oil wells and deep artesian wells, whenv there is not spontaneous dow, the well may either be pumped, or be swabbed or hailed, these operations didering essentially in the character el the device employed, and in ways el applying the power necessary to lift the duid out or the Well. Pumping may be perliormed by pumps having submerged pump cylinders, of good mechanical construction with well machined bores, lowered beneath the level ci the liquid in the well, and having the usual pumping equipment ont a lorcing plunger or rod extending to the t'op of the well and suitable valves for taking in and emitting above the pump cylinder a charge of the liquid at each stroke oi the pump. v`duch pumps are usually singlestroke devices, the great distance to the sur- :tace ot' the liquid from the surface of the earth often precluding the transmission ot any power by. a pushing stroke on the pump rod, and necessitating a slow rate of pumping. Jilticulties of operation and expense of good pumping mechanism have led to the general practice oi swabbing or hailing by utilizing the tubular well casing as the cylinder of a lift pump, the piston usually comprising a weighted tubular stem attached to the bottom ci a ilexible wire hoisty ing cable, this stem having a duid passage lill liquid. The pressures to which packing elements between the pump rod or swab stem and the pump cylinder or the well casing. are exposed are very great., ln'the case of swabbing, the great pressures and the rough, variable and broken surface of the well casing make it difficult to hold the Vheavy liquid column reliably and efficiently and result in destruction of the usual paclrn devices which often are worn out alter a ew worlring strokes only.

@bjects oli this invention are to provide a lifting plunger tor pumping or swabbing adapted efficiently to torni a duid tight `concasing; to provide a packing capable ot nection with the walls ci a cylinder or well m withstanding very great pressures and adapted to form al fluid' tight connection w1th a relatively imperfect cylindrical surface; to provide improved reenlorcedmeans 75 for protecting thepaclring against collapse by pressure and againstloclring into, or being torn or cut by, brolren or irregular surfaces in rough and uneven4 pipes, and thus to prevent mutilation and injuryv to the @0 packing; 'and in general to provide a plunger packing having features of construction ensuring prolonged eilicient perlormance in the indicated environment.

a portionoi a swahdn a well casing; ao

lig. 2 is a top plan view of the packing shown in Fig. l;

lig,l lis a section on the line '3-3 of Fig..

l; and

The invention will now he described with Fig. Il is a vertical sectional elevation of t5 another form of paclring or cup.

Referring to the drawings, the swab may comprise a tubulaistem l which is adapted to be lowered into a cylindrical well casing 2 having abutting pipes held 'together by collars 3. il portion of the stem l may be exteriorly screw threaded to receive nut l on which rests agcalyx 5 which is provided with a concave upper surfae 6 to support the packing cup or sleeve 7, of which only one of the series recommended to be used is shown in Fig. l.

'lihe packing cups may be flaring trusteco'nical bodies having an annular section or heel 8 which rests in the concave upper surferred form of packing comprises a solid ot revolution integrally molded comprising portions of diierent grades-or qualities of .the molded rubber compound (or rubber substitute) one of which kinds of compound, whenA subjected to vulcanizing under `the same temperature and pressure as the other will become relatively stift1 and whereas the other kind of compound under the same treatment will become a relatively flexible and relatively yielding resilient body. For example, the cup 7, Fig. 1, may comprise a. heel portion made as an `annulus 8, as illustrated by the moreheavily shaded section, of a rubber compound heavily charged with sulphur, and if desired with other vulcanizing agents or facilitators, and so adapted when finished by subjecting it in a mold to a vulcanizing heat and pressure to )resent a very great elastic resistance to de ormation of shape by crushing or shearing, but nevertheless to be reasonably extensible under great pressures. Rubber com- ,pounds capableof producing the results indicated are well known in the art.

The remainder of the cup 7 is made of a softer, less heavily sulphureted material, and therefore when vulcanized manifests more easily extensible and vmore flexible inished structure than the annulus 8.- Preferably the integral cup 7 is a solid of revolution approximately ot' the form shown in the drawings, the portion above the calyx 5 comprising in general a flaring or conical annular solid tapered away to a lip 9. lt may be desirable under some conditions to vary the proportions of the packing cup, especially the relative dimensions of the annulus 8.

A preferred construction comprises a reentorcement serving as a guide and protector for the exterior surface of the cup 7 and adapted to prevent the upper-portion or lip 9 or other portions of the packing from catching in projections and from entering deeplyinto openings, such as those between the ends ot' the casing pipe sections, as shown 'in Figure 1. The reenforcement comprises a spaced series of radially spaced flat metallic plates each consisting of articulate segments 10 and 11 having rounded ends 12 and anchored end ortions firmly7 'embedded in the cup 7. Pre erably the segments l0 and 11 are in longitudinal align- `ment and may be pivotally connected, as inrigid,

maare/li dicated inv Fig. 3, the abutting ends of the plates being shouldered to provide a smooth exterior surface and pivoted, as by a loose rivet 13.- Preferably the reenforced cups 7 yare molded at one operation in a mold bedded within the substance of the cup as to cause the exterior surface of the plates to coincide with the exterior surface ot the body portion of the cup. Under the pressures of use there is nosensible leaking of liquid between the material of the cup 7 and articulate segments 10 and 11.

As shown in Figure 1 the ring 4 and calyx 5 are screwed up into the desired'position on the stem 1 in order to force the packing cup, 7 against the casing sleeve 15,-an annular shoulder 1G being provided in the heel 8 ot the cup against which the sleeve 15 is adapted to bear. i

As so mounted, the upper .or outer segments 10 severally can yield outwardly with portions of the cupv under very great pressure developed within the cup and so permit a satisfactory fluid-tight .contact be-Y tween the outer portions of the cup and the wall of the well casing 2. Any projection encountering the exterior surface of the packing when under pressure will, however., distort the cup and displace one or more of the segments 12, and thus result inthe local depression only ot' the margin ot' the cup, which is the desired el'ect. @t course, should the pressure be verygreat then one or more of the segments 11 will also yield, but under ordinary conditions et"` 1use the segments 11 are not depressed but serve to reenforce the lower or heel portion 8 of the cup in normal uniexed position. lhe plates 12 not only serve as skids, runners or guides for the cup 7 but also to guard the cup from expanding into the grosser irregularities in the interior cylindrical surface of the well casing without preventing liquid tight contact with normal surfaces. Y

Under some conditionsof use the packing 17 and reenforcing plates 18 and 19 may have the form shown in Fig. 4C in which the lower or heel portion 20 ot the cu comprises a relatively rigid annulus whic extends well into the calyx 2l, the latter serving to prevent the expansion of the lower or heel portion of the cup. In this form, the reenforcements mayk constitute short segments 19 extending a slight distance into the calyx 21 and having a portion embedded inv the annulus 20, the lates 18 being pivoted tothe plates 19, and prefervtheir points of connection.

` sures comprisin 1,563,164 v f B ably having a portion 22 of their edges defining a cylinder and a portion 23 de lining a cone, these exterior surfaces conforming to and coinciding with the exterior surface of the packing cup 17. l

llt will be observed that the expansion of the packingr described involves a stretching increase o heel which has been contrived to be without restriction by metallic reenforceu'ient. Such stretching on the contrary is facilitated by the comparatively7 small proportion ot' the circumferential dimension oi. the packing occupied by the lesser cross sectional area of the metal reenforcements which nevertheless are highly rigid between Therefore the packing cup reenforcements described are highly edective as skids to bridge depressions or guides to avoid collisions with projections from the casing wall and as stid'ening resistance against longitudinal and radial pressures.

ll claim: s

l. Packing comprising an vexpansible solid of revolution having therein radially placed. and longitudinally extending dat articulate metallic reenforcements.

2. Packing comprising an eirpansible solid of revolution having therein radially placed and longitudinally extending datl articulate metallic reenforcements having outer edges thereof coincident with a corresponding surface of the solid.

3. Packing comprising a vulcanized rubber compound solid of revolution having therein .articulate metallic reenforcernents of greater radial than circumferential dimension moulded into said packing and at outer edges coincident with the peripheral surface of said solid ot revolution.

Il. A cup adapted to ack the space between a liftin stem an al cylindrlcal tube of imperfect orm and to resist great presheel annulus an a bod portion ot relative-7 ly greater flexibility, in combination with the perimeter of the cup or a stift moulded compound lflat metallic articulate Areenforcements. ra-

wells, the combination of a stem and a packing comprising an expansible solid of revolution havingtherein radially placed and longitudinally extendingiiat metallic reenforcements, each reenforcement consisting of at least two articulate lsegments, and means for supporting one joint of the articulated reenforcement in relation to the stem.

6. In a swabbing device for use in deep wells, the combination of a stem and a packing comprising a moulded flaring packing cup having a lip port-ion more flexible than its heel portion, the regions of relatively didering flexibility comprising materials respectively diifering in iexibility' andrigidity, and articulated fiat metallic reenforcing plates moulded into the cup and having one series oit like members of said articulated arts mounted in a constant relation to sai stem.

7. A reenforcement plate of metal for packing cups comprising elongate dat segments pivoted together.

8. A reenforcement plate of metal for packing cups comprising elongate flat articulate segments having apertures therein and edges terminating at one end in a rounded portion.

9. A liquid driving plunger comprising a stem, a calyx on said stem, means for supporting the caly'x, an 'expansible ilexible rubber compound cup having a heel in the calyx, means for holding the cup against the" calyx and a series of i'eentorcements moulded into said cup, each reenforcement comprising two orl more articulate segments'lying substantially longitudinally and radially of said heel and having an ed e coincident with a corresponding surfacer o the cup.'

Signed by me at Manville N. J. this 19th day of Januar 1925.

GE BGE CHRISTENSON.

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