US3079205A

US3079205A - Expansible swab cups

Info

Publication number: US3079205A
Application number: US121873A
Authority: US
Inventors: Dale G Hugley
Original assignee: Skinner Brothers Rubber Co
Current assignee: Skinner Brothers Rubber Co
Priority date: 1961-07-05
Filing date: 1961-07-05
Publication date: 1963-02-26
Anticipated expiration: 1980-02-26

Description

2 Sheets-Sheet 1 INVENTOR Dale 6. Hug/ey 8 a a a n a@ 2 F//// f 7 aaa ATTORNEYS D. G. HUGLEY Feb. 26, 1963.

ExPANsIBLE swAB cups Filed July '5, 1961 2 Sheets-Sheet 2 Filed July 5, 1961 INVENT OR ATTORNEYS with a central or medial cylindrical portion 11 and end portions or necks 12 of reduced diameter, the sections or necks 12 joining the mediai portion 11 through tapered or bevelled intermediate portions 13. The swab body is also formed with `an axial borelf extending throughout the length of the swab, the swab being longitudinali-y symmetrical so that it may be employed with either of the necks in a downward position. Suitablerlayers of reinforcing-material, such as the iibrous elements 15 are desir-ably embedded in .the body 1G of the swab adjacent the wall ofthe bore 14 and extend throughout the length of the swab. Woven fabric such as canvas has been found quite suitable to employ for this purpose.v Outwardly of the layer or laye-rs of reinforcing material 15, cylindrical metallic ferr-tiles 16 yare embedded in the body ofthe swab closely adjacent the outer walls or peripher-ies'of thenecks `12 and extend in' alined Vrelationship from the upper land lowerends of the swab into the en larged medial portion 11. It will `be noted that the inner ends of the sleeves or fel-rules 16 are spaced apart and are disposedJ approximately equidistantly from 4the outer periphery of the medial portion 11 and the wall of the bore 14. Y

In previous swabs of this type in which the metallic reinforcing ferrules are disposed adjacent the wall of the bore`14, and particularly where such ferrules do not extend into the relatively. thick walled medial portion, it has been found that the swabs tend to fail, ysometimes prematurely, inthe intermediate tapered portions'l, the body of the swabvbeing forced outwardly over the inner end of predominantly the. lower ferrule and resulting in cutting," abrasion, and premature loss of. etectiveness of thefswab in thezone o the lowermost intermediate portic'irrflnV With the present structure, such cutting, wear-V ing'and abrasive vforces are effectively directed into the area of the medial portion 1K1, which, presenting a. greater `wall.thickness, more effectively resists such forces resulting in prolonged wear and a longer effective operating life for ftheswab.Y The tendency of the swab to out and tear outwardly over the upper edge of the lowermost reinforcing ferrule, at which point the greatest load-isapplied, is. effectively resisted, and yet the desired flexibility of theswab i-s retained permitting it to distort to some extent under an applied load as illustrated in FIG. 2 of the drawing. In use, the swabr is mounted in the conventional fashion upon any type of suitable mandrel 17 carrying the usual upper andlower thimbles 18 which receive and confine the neck portions 1,2, of the swab.

Insome instances, fthe body of the swab may tend toV swell while in contact with certain types of liquids, and some diiiculty may be encountered in replacing a swab ona mandrel or primarily, in removing a swab from such mandrel. For this reason, the swab of FIG. l may be modiiied as illustrated in F165. 3 by including therein a pairot' thin metallic liners 19 offcylindrioal configuraltion'and extending from each end of the axial bore 14 toward the medial portion thereof. Desirably, the liners 1'9 are bonded, vulcanized orotherwise adhered to the wall ofthe bore 14 so as to prevent their displacement therefrom although such adhering is not necessarily essential. In addition, Ithe liners 1.9 should be coextensive with and radially alined with the ferrules 16.

Itis pointedout thatvthe ferrules 16 should be of approximately the same length in order thatthe swabV will be fully reversible upon the mandrel 17 and employable with either of the` neck portions 12 disposed or extending downwardly, and-that the spacing between the inner ends of Ithe ferrules should be such that :the swab will carry both heavy and light liquid loads. 'If the spacing istoo large the swab may fail under high loads, andif such.. spacing is too small, the swab becomes too rigid and will not always pick up relatively light loads. In the vcase of a swab for two inchrwell tubing, the spacing between the inner ends oflthe ferrules should be of .the magnitude of 1/2 of one inch'.

A modified form of the swab is shown in FXGS. 4 and 5 which includes a cylindrical body 2l) formed of rubber, synthetic rubber, or .any other suitable elastomer and having a more or less cylindrical center or medial portion 21 adjoined at e-ach end by bevelled or Atapered end sections 22 of lesser outside diameter than the medial portion 21. The swab is formed with an axial bore 23 which receives the mandrel 24 carrying an upper shoulder 25 and a lower removable shoulder member 26 between which the swab is confined. Cnc or more layers of fibrous reinforcing material 27,A such as a suitable cotton fabric of the nature of canvas, are embedded the swab lbody 2).adjacent the wall of the axial bore 23, the layers desirably extending approximately throughout the length of the swab body. Outwardly ofthe layers of iibrous reinforcing material, a pair of cylindrical, metallic reinforcing sleeves or ferrules V28 are embedded or bonded in the body of the swab, oneI of the ferrulesV being disposed at one end of 'the swab andl the other at the other end of the swab. Thevouter ends of the ferrules 28 are spaced slightly from the; ends of the swab so that relatively thin sealing layersof :the resilient material from which theswab is formed are providedat-each end of the swab for sealing against the, upper and lower shoulders, This arrangement also completely' encases the outer ends of lthe fer-rules 28 so as to eliminate :the possibility or likelihood that the application` of hydrostatic pressure o r other forces will cause the resilient materiall in the `swabito tend to tear away from the outer ends of the ferr'ules. As shown in FIG.

4, the ferrules are positioned in the youter, half of the endV sections 22AV of the swab, but are not as closely adjacent the outside wall ofsuch end portions astthe ferrules 16 ofthe irst form ofthe invention.

The inner ends of the fop-rules ZQS-fare spaced 'apart and extend into the'thiclc medial section 21 of the swab,k said inner 'endsbeing substantially equidisftantly spaced between the outer wallof the medial portion 21 andy the wallet' the axial bore23, similarly tothe spacing ofthe inner end of the ferrules 16 of the rst form of the invention.

In all those forms of the invention, there is desirably a slight clearance, of the magnitude of 1/3'2 of aninch b etween the outer wall of the medial portionsof the swabs andthe inner wall ofthepipe orconductor through which the swaby 'is being passed,A this clearance being present when the swab is in its relaxed position during yits downwardpassage throughthe pipe or conductor. Upon upward movement ofthe swab, however, such clearance, whichis deemed too small to be illustrated in the drawing, isinsufcient to accommodate the body of liquid attempting to flow downwardly, and hence, a hydrostatic pressureis applied to the swabs causing them to distort slightly downwardly, as shown in FIGS. 2 and 5 and to seal against the inside wall of the pipe or conductor in which the swab is positioned. In the case of the form of the invention shown in FIGS. 4 and 5, this isillus trated bythe slight dropping ofthe upper end of the swab: from rthe upper shoulder 2S'when the swab -is in its seal-- ing and lifting position. The modification of FIGS. 4 and 5 functions i-n much -thevsame manner as the rst described moditcation, and the outward shifting of the reinforcing,metallicV ferrules 28 accomplishes the samev desirable result of concentrating the destrictive forces. applied *tov the swab in lthe relatively thick medial portion `and preventing premature or early failure ofthe swab due tto cutting or abrading in the thinner sections of the swa Similarly to the iirst form'of the invention, the fo1m )ust described may receive upper and lower` liner sleeves- 29 positioned in the axial bore 23 and desirably vulcanized or bonded to the wall thereof. Again, these relatively thin lliner sleeves minimize any tendency of the swab to stick or Iseize upon the outer wail ofthe mandrel 24, and shouldbe coextensive with the ferrules 28.

A further form of the swab as a swab cupis shown ink FIG. 9 and includes a body 30 having a tapered or bevelled lower end 31 for reception in the usual thimble 32 carried upon the mandrel 33. An inner sleeve 34 is bonded in the bore 35 of the body 30, similarly to the sleeves 19 and 219 of the .previously described forms of the invention, for ease of removal of the cuprfrom the mandrel. Upwardly of .the sleeve 34, the bore 35 is enlarged to a first counterbore 36 adapted to receive the lower end of an elongate sleeve 37 which spaces the cup from the next upper cup. Toward the upper portion of the body Sti, the bore is further enlarged to form a second counterbore 3S extending upwardly to the upper end of the cup and daring outward-ly as shown at 39 to merge into a rounded upper lip dit which, as shown at 41, ares slightly outwardly from the main body of the cup 31'?. One or rseveral layers of reinforcing material such as conventional reinforcing fabric or canvas 42. are embedded in the body Sti and extend from the lower end thereof upwardly past the outer surface of the sleeve 34 and upwardly through the body into the lip 40.

The reinforcing ferrnle 43- is embedded in the lower portion of the swab cup body outwardly of the fabric 42 and extending from approximately the medial part of the tapered lower end thereof upwardly into the substantially cylindrical medial portion well above the juncture between said medial portion and the tapered lower end. it is to be noted that the ferrule 43 is spaced aproximately medially between the outer wall of the main cylindrical portion of the cup body and the wall of the first counterbore 36. Here again, the inclu-sion and positioning of the ferrule 413` shifts the area of most severe wear incurred by the outer wall of the swab cup upwardly from lthe point at which the tapered lower end 3l `enters the thirnble 32, and transposes the area of severe wear to `the thickest portion of the cup wall, the portion most capable of withstanding prolonged and severe wearing conditions. It will be lseen that in all the forms of the invention the dimensioning and positioning of the

ferrules

16, 28 and 43 move the point of wear away from the thinner walled portions of the swab, and in the case of the first vand last modifications, shifts the point of wearing away from the point at which the tapered end of 'the swab enters the ysupporting thirnble.

in all forms of the invention, there has been provided a new and different swab having its metallic reinforcing ferrule or ferrules shifted radially outwardly and extended into the medial portion of the swab for concentrating destructive forces therein. In addition, the fabric reinforcing layers have been shifted inwardly of the metallic ferrules so as to provide swabs of maximum resistance to applied loads and destructive forces as well as extended maximum sensitivity to both light and heavy loads.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to `secure by Letters Patent is:

l. An expansible swab including, a resilient swab body having an axial bore, the body having a medial portion and an end portion, the medial portion being larger in diameter than the end portion, a metallic reinforcing member embedded in the swab body and extending from the end portion into the enlarged medial portion of the body, the reinforcing member encircling the end portion and being disposed closely adjacent the outer wall thereof, and brous reinforcing embedded in the swab body between the axial bore and the metallic reinforcing member.

2. An expansible swab including, a resilient swab body having an axial bore, the body having la medial portion and an end portion, the medial portion being larger in diameter than the end portion, a cylindrical metallic reinforcing member embedded in the outer wall ofthe end portion and extending into the enlarged medial portion of the swab body, and brous reinforcing embedded in the swab body between the axial bore and the metallic reinforcing member.

3. An expansible swab including, a resilient swab body having an axial bore, the body having a medial portion and an end portion, the medial portion being larger in diameter 'than the end portion, ta cylindrical metallic reinforcing member embedded in the outer half of the end portion and extending into the enlarged medial port-ion of the swab body, and iibrons reinforcing embedded in the swab body between the axial bore and the metallic reinforcing member.

4. An expansible swab as set forth in claim 3 wherein the fibrous reinforcing is at least one layer of reinforcing cloth.

5. An expensible swab las set forth in claim 3, and a metallic liner within the axial bore.

6. An expansible swab including, an approximately barrel-shaped swab body formed of an elastomer and having an axial bore, the swab body having reduced end portions and a medial portion of greater diameter than the end portions, cyiindrical metallic reinforcing members embedded in each end portion of the swab body and extending into the medial portion, the inner ends of the reinforcing members being spaced apart :and being disposed approximately equidistantly from the wall of the axial bore and the periphery of the medial portion, and brou-s reinforcing embedded in the swab body between the axial bore and the metallic reinforcing members.

7. An expansible swab as set forth in claim 6, and metallic liners within the axial bore.

8. An expansible swab as set forth in claim 6, wherein the reinforcing members are disposed closely adjacent the outer peripheries of the end portions and extend substantially to the ends of the swab body.

9. An expansible swab as set forth in claim 6, and a pair of metallic liners in the axial bore, the liners being coextensive with and radially alined with the metallic reinforcing members.

l0. An expansib'le swab including, a resilient swab body having an axial bore, the body having a medial portion and an end portion, the medial portion having a greater wall thickness and being larger in diameter than the end portion, a met-allie reinforcing member embedded in the swab body and extending from the end portion into the enlarged medial portion of the body, the reinforcing member encircling the end portion and having its outer end closely adjacent the outer wall thereof, the inner end of the reinforcing member being disposed approximately equidistantly from the wall of the axial bore and the periphery of the medial portion, and fibrous reinforcing embedded in the swab body between the axial bore and the metallic reinforcing member.

ll. An expansible swab including, a resilient swab body having an axial bore, the body having an enlarged medial and reduced end portions, the medial portion having a greater wall thickness than the end portions, metallic reinforcing members embedded in the swab body and extending from the end portions into the enlarged medial portion of the body, the reinforcing members encircling the end portions Iand having their outer ends closely adjacent the outer walls of the end portions, the inner ends of the reinforcing members being disposed approximately equidistantly from the wall of the axial bore and the periphery of the medial portion, and fibrous reinforcing embedded in the swab body between the axial bore and the metallic reinforcing members.

l2. An expansible swab as set forth in claim l1 wherein the fibrous reinforcing is at least one ylayer lof reinforcing cloth.

13. An expansible swab cup including, a resilient swab body having an axial bore, the body having a tapered lower' end and a medial portion of greater wall thickness i 2?302'9Q205A n l 1' e than 4the lower end, theA axial bore being enlarged in the nthe swab bodygbetween the axial bore4 andthe metallic upper pofrii'on ofthe body to form a sealing lip on the reinforcing member. Y upperv end of `the cup, a metallic reinforcing member the medial' portion, and bous reinforcing embedded

Claims

1. AN EXPANSIBLE SWAB INCLUDING, A RESILIENT SWAB BODY HAVING AN AXIAL BORE, THE BODY HAVING A MEDIAL PORTION AND AN END PORTION, THE MEDIAL PORTION BEING LARGER IN DIAMETER THAN THE END PORTION, A METALLIC REINFORCING MEMBER EMBEDDED IN THE SWAB BODY AND EXTENDING FROM THE END PORTION INTO THE ENLARGED MEDIAL PORTION OF THE BODY, THE REINFORCING MEMBER ENCIRCLING THE END PORTION AND BEING DISPOSED CLOSELY ADJACENT THE OUTER WALL THEREOF, AND FIBROUS REINFORCING EMBEDDED IN THE SWAB BODY BETWEEN THE AXIAL BORE AND THE METALLIC REINFORCING MEMBER.