US3513511A - Slip assembly - Google Patents

Description

May 26, 1970 C. D. CRICKMER SLIP ASSEMBLY 2 Sheets-Sheet Filed June 5, 1968 INVENTOR. Cfia rles l2 Crick mar.

y 26, 1970 c. D. CRlCKM ER 3,513,511

SLIP ASSEMBLY Filed June 5,1968 I 2 Sheets-Sheet 2 INVENTOR. Cfiarles D. Crickmer.

United States Patent 3,513,511 SLIP ASSEMBLY Charles D. Crickmer, 12923 Memorial Drive,

Houston, Tex. 77024 Filed June 5, 1968, Ser. No. 734,671 Int. Cl. A44b 21/00 US. Cl. 24-263 12 Claims ABSTRACT OF THE DISCLOSURE A slip assembly including a plurality of slip bodies held in spaced orientation with respect to each other by one or more resilient, self-supporting ring shaped members passing through openings in the slip bodies.

Slip assemblies presently used with well drilling and production apparatus comprise a plurality of elongated rigid slip members hingedly connected together at the ends thereof by suitable means such as pin and ear means. The pin means and the relatively short arcuate transverse chord lengths of the slip members facilitate a somewhat even stress distribution throughout the entire slip assembly for slight pipe diametric variances, all as is well known in the art. As the drill collar wears, surface irregularities appear to which slip assemblies as presently constructed cannot conform, thereby, resulting in an uneven distribution of loading to the slip members which causes excessive wearing condition and possibly failures. Additionally, the pin and ear means interrupt the generally smooth continuity of the slip assembly thereby resulting in collection points for mud and the like which shorten the life of the slip assembly because of a rust buildup and hinder efiicient operation.

The flexible characteristics of an Elastomer Hinge of the present invention allows each slip member, in addition to adjusting to diametric variances, to conform to any surface irregularity thereby maintaining a uniform stress distribution among the slip members. Additionally, the relatively smooth continuity of the slip assembly is maintained, thereby minimizing mud collection and buildup points.

Other results and advantages of the present invention will become apparent to one skilled in the art upon read ing the following description of preferred embodiments in which:

FIG. 1 is a top plan view of one embodiment of a slip assembly of the present invention;

FIG. 2 is a view taken along the lines 2-2 of FIG. 1 with portions of the slip bodies not being shown for clarity of illustration;

FIG. 3 is a partial perspective of certain elements of the slip assembly of FIG. 1 showing further details of construction;

FIG. 4 is a partial perspective of certain elements of the slip assembly of FIG. 1 showing further details of construction and the deleted lines of FIG. 2;

FIG. 5 is a perspective view of certain elements illustrating another embodiment of the present invention;

FIG. 6 is a view taken along the lines 6--6 of FIG. 5;

FIG. 7 is a view taken along the lines 77 of FIG. 5;

FIG. 8 is a partial perspective of a slip assembly utilizing the structure shown in FIG. 5;

FIG. 9 is a partial perspective of certain elements of the slip assembly of FIG. 5 showing further details of construction;

FIG. 10 is a partial perspective view of a slip assembly illustrating still another embodiment of the present invention; and

FIG. 11 is a perspective view of an element of the slip assembly of FIG. 10.

3,5 l 3 ,5 l I Patented May 26, 1970 ice Referring to FIGS. 1-4 a slip assembly 10 of this invention includes a plurality of arcuately spaced, similar or identical elongated rigid slip bodies 12 formed in a flange and rib type construction from a material capable of withstanding the rough use characteristic of oil field operations. Each slip body 12 has lower and upper portions 14 and 16, respectively, a forward surface 17 suitably adapted for receiving a toothed pipe gripping liner of well-known construction, and a rearward surface 20 with a generally arcuately shaped downwardly tapered section 22 at lower portion 14, which section 22 is suitably shaped for snug abutment with a surface portion of a rotary table supported frusto conically shaped bowl of well-known construction.

Upper portion 16 of each slip body 12 includes longitudinally spaced, rearwardly transversely extending upper and lower lugs 23 and 24, respectively, suitably adapted for pivotally supporting familiar slip handles (not shown). A rearwardly and transversely extending upper section 26 extends from upper portion 16 immediately below upper lug 23 and has a generally rectangular shaped opening 28 extending therethrough transversely of the slip body .12. An intermediate section 30 extends rearwardly and transversely from portion 16 below the lower lug 24. Section 30 has an opening 32 extending therethrough, which opening 32 is preferably identical in shape to opening 28 and extends in the same direction as opening 28. A lower section 34 extends from an intermediate portion of lower portion 14 and has an opening 36 therethrough preferably identical in shape and extent to openings 28 and 30.

The slip bodies 12 are supported relative to each other by novel hinge or connecting members 40 which are preferably formed from a self-supporting resilient elastomeric material such as polyurethane, neoprene or the like, which possess suitable physical properties such as hardness, tensile and elongation, for purposes hereinafter described.

When unrestrained or in free form connecting members 40 are in the form of a partial or substantially complete ring with the ends 44 thereof being spaced from a few to approximately ninety degrees from each other. In normal use a slip assembly 10 is placed about and removed from an elongated member, such as a pipe of known outside diameter, and the ends 44 are spaced from each other to permit such member to pass freely therebetween. Consequently the material from which the members 40 are formed must have a resiliency to permit the slip bodies 12 to move into engagement with the member to be supported and, since members 40 have such resiliency upon subsequent withdrawal out of engagement with the supported member, the members 40 return to their original or substantially original form. Inasmuch as the members 40 have such resiliency the ends 44 can be moved away from each other to permit the supported member to be received therebetween; however, a spacing of ends 44 to permit free passage therebetween of a supported member can be utilized. Further since slip assemblies constructed as herein described are built in various sizes to cooperate with various diameters of received members the spacing between the ends 44 varies in accordance with the size of the member with which it cooperates.

In FIGS. l-4 member 40 comprises a locating segment 42 and a locking segment 50 which overlie each other for the accurate extent of the connecting member 40. Locating segment 42 has an arcuate body portion 43 with a plurality of projections 46 extending vertically therefrom. A projection 46, or a suitable portion thereof, is provided at each end of segment 42 and the projections 46 intermediate the end projection 46 have the sides thereof spaced from the sides of the arcuately adjacent projection 46 a distance slightly greater than the transverse length of the openings 23, 32 and 36. The total vertical height of the locating segments 42 is less than the height of the openings 23, 32 and 36- along the axis of the slip bodies 12 to permit a segment 42 to pass therethrough.

In assemblying a slip assembly 10 as shown in FIGS. 14, a first locating segment 42 is initially inserted through adjacent openings 23, 32 or 36 of a desired plurality of slip bodies 12. The slip bodies 12 and segment 42 are moved relative to each other such that the arcuately spaced sides of projection 46 extend axially (with respect to the bodies 12) beyond the openings 23, 32 or 36.

Projections 46 define a plurality of uniformly, arcuate spaced notches 48 there'between. Although the end projection may be of any desired size, as shown, a projection 46 is split to form a pair of half projections 46a and 46b.

Each locking segment 50 is formed, preferably, from the same material as segment 42, and has a radial dimension the same as segment 42 with which it is used. The axial linear dimension of segment 50 is of such a magnitude that when segment 42 is worked through an opening 28, for example, and a slip body 12 indexed in a' notch 48, segment 50 will fit snugly between the base of segment 42 and the end of opening 28 opposite the base of segment 42. Such axial linear dimension of segment 50 also permits unimpeded insertion of segment 50 through the space defined between the base of segment 42 and the opposed end of opening 28, for example, when slip body 12 is indexed in a notch 48. Thus, segment 50 serves as a locking means for member 40, in the sense, that is, of holding a slip body 12 against longitudinal movement with respect to member 40.

Each of the projections 46a and 46b, has a vertically extending opening 54 therethrough suitably sized to suitably receive any well known fastening means such as a pin 56. Openings 54 are radially positioned to register with identically positioned and shaped openings, not clearly shown, through segment 50. Thus, when slip bodies 12 are indexed in notches 48 as desired and in the manner described hereinabove, pins 56 are inserted through the registering openings through segments 42 and 50.

FIGS. 2 and 4 illustrate a hinge means 40 passing through each of the openings 28 and 32 of upper and intermediate window sections 26 and 30, respectively, with a slip body 12 received in each notch 48. The number of projections 46 can be varied by changing the arcuate dimensions accordingly for accommodating a more or less number of slip bodies 12, as desired, It should be understood that a hinge means 42 can be worked through openings 36 of the lower sections 34, if so desired. Any combination of three, two, or one hinge means 42 can be used as desired, however, two or three hinge means 42, of the type described, used in the slip assembly 10 will provide a better support, relative a single hinge means, for holding the slip bodies of such assembly in an erect relationship when not being used.

FIGS. -10 illustrate another embodiment of the present invention. The hinge means 60 shown, is formed from a resilient, self-supporting elastomeric material as heretofore described, and includes a single hinge or connecting band member 62, axially split for expansion and compression in the same manner as hinge means 40 described hereinbefore. Member 62 has an axial dimension substantially the same as the longitudinal'dimension of openings 28, 32 and 36, and a radial dimension substantially the same as the transverse dimension of such openings. Members 62 includes a plurality of uniformly circumferentially spaced radially extending circular cross-section cavities 64 formed therein intermediate the axial ends thereof. The circumferential spacing of the cavities 64 is of a magnitude to receive a slip body 12 therebetween as hereinafter described. Each cavity 64 has at the inner end thereof an inwardly extending flange which forms a generally rectangularly shaped opening 66 at the inner end thereof of a smaller transverse dimension than the diameter of cavity 64 and which defines an inner wall portion 69. A button member 70 is received in part through inner opening 66 of each cavity 64, which button member 70 extends radially outwardly from the inner surface of member 62 an amount to be defined hereinafter. Each button member 70 comprises a wedge shaped face portion 71 at the free end thereof which is secured to the inner end of a generally rectangular crosssectioned shank 72 having essentially the same shape and depth as inner opening 66. Shank 72 terminates within cavity 64 and has a generally rectangular plate portion 73 of larger dimensions than shank 72 located within cavity 64. The button member 70 is fixed with respect to member '62 by working the plate portion 73 through inner opening 66 until such plate portion 73 is within the cavity 64 and the bottom surface of the face portion 71 in flush with a portion of the inner surface of band member 62. As shown in FIG. 7, a pair of adjacent cavities 64 receive a button member 70 having the wide dimension of the wedge of the face portion 71 thereof facing in the direction of one axially extending end of member 62 and the other button member 70 having its wide dimension of the face portion 71 thereof facing in the direction of the other axially extending end of the member 62. The wall portion 69 is of a size, to provide a firm support for a button member 70 while at the same time permitting a button member 70 to be depressed into the associated cavity 64 when an operator applies a radially outwardly directed hand force on the portion 71. Accordingly, a member 62 can be worked through an opening 28, for example, of a slip body 12 with the wall of the opening 28 riding over the portion 71 of the button member 70 first encountered to depress such button member into cavity 64. When the slip body 12 is disposed between a pair of successive button members 70 the first encountered button member will be urged by the wall portion 69 into its original orientation relative to member 62. If it is desired to move a slip member 12 farther along the member 62 alternate button members 70 will have to be depressed until such slip member is disposed where desired on band member 62. Thus, a slip body 12 can be disposed, as desired, between a pair of successive cavities 64 and held against free circumferential movement on band member 62 by the radially inwardly projecting button members 70 in such successive pair of cavities 64. The wide dimension of the face portion 71 of the button members 70 extend radially of member 62 a magnitude sufficient to safely restrain a slip body 12 from circumferentially shifting beyond the limits defined between a pair of successive cavities 64.

Regarding the embodiment of FIGS. 5-9, radially outwardly extending fingers, or the like, can be molded, or otherwise secured, on outer radial surface portions of member 62 within the confines of the zones defined between pairs of successive cavities 64 in such a position to fix, together with button members 70, the circumfreential orientation of the longitudinal centerlines of slip bodies 12 with respect to the member 62. It should be understood that, as in the preferred embodiment of FIGS. 1-6, that one, two or three members 62 can be used for holding slip bodies together to form a slip assembly. It should be further understood that other forms can be given to the button members 70 without departing from the scope of the present invention.

FIGS. 10 and 11 illustrate yet another embodiment of the present invention. FIG. 10 shows a partial slip assembly including an elongated slip body having an upper section 91 adapted to pivotally support a slip handle (not shown) and a downwardly tapered rearward lower section 92 adapted to be suitably abuttingly received in a downwardly tapering slip bowl, and a forward lower section 93 suitably adapted to fixedly hold a toothed pipe gripping liner 94 of well known construction.

Upper section '91 of slip body 90 has a longitudinally extending, generally rectangular cross-sectioned passageway 95 therethrough, which passageway 95 extends longitudinally over a greater portion of upper section 91. The hinge or connecting means for holding the slip bodies 90 together in an erect slip assembly, includes a band 97 having an axial length thereof essentially equal to the longitudinal length of passageway 95 which is formed from a resilient, self-supporting elastomeric material as heretofore described. Band '97 is preferably initially formed as an annulus and then axially slit therethrough to expand for providlng an opening 98 defined between the axially extending ends of the band 97. Such opening 98 is of a magnitude sufiicient to permit a radially outward movement of the ends of the band 97 an adequate distance which allows the insertion of a pipe of known outside diameter to pass therethrough. Band 97 is provided in both axial ends thereof with a plurality of identical uniformly circumferentially spaced radially extending semi-circular cross-sectional slots 100. The slots 100 of one axial end of band 97 lie on common axial lines of band 97 with the slots 100 of the other axial end of band 97. Each pair of opposed slots 100 is arranged to register with coaxially aligned circular openings 102 and 104 and semicircular cross-sectional shaped grooves 96 all of which extend transversely through the upper section 91 having the central axis thereof in the same plane as the longitudinal end surfaces of passageway 95. Openings 102 and 104 extend, respectively, through the forward and rearward face portions of upper section 91 into passageway 95 and groove 96 extends therebetween. A rollpin 110 or the like is suitably fitted through the respective registering openings 102 and 104 and groove 96 and slots 100 to fix the respective slip bodies 90 in upright circumferential spacing relative each other.

The hinge means of FIGS. 10 and 11 can be formed of two or three bands of the type described. Likewise, circumferentially spaced radial circular openings 120 can be formed through band 97 intermediate the axial ends thereof in combination with or in lieu of slots 100. Openings 120, like slots 100, are disposed to form opposed pairs of openings lying on common axial lines of band 97. Accordingly, the openings 102 and 104 are shifted towards each other so that the openings 102 and 104 will register with the openings 120 when a slip body 90 is properly oriented on band 97. Thus, a roll-pin or the like can be suitably fitted into the registering openings to thereby fix the slip body 90 against circumferential movement along band 97.

It should also be understood that instead of using rollpins and slots for locking means, band 97 of FIGS. 10 and 11 can be readily adapted to accommodate biased button members such as the button members 70 illustrated in FIGS. -9 herein. Additionally, the roll-pin 110 and the openings and grooves necessary therefor as illustrated in FIGS. and 11 can have cross-sectional shapes other than the circular cross section shown, for example, square or rectangular.

While I have shown and described certain present preferred embodiments of the present invention it is to be understood that the invention is not limited thereto but may be otherwise variously embodied.

What is claimed is:

1. A unitary slip assembly comprising: an arcuately shaped connecting means having spaced ends which define a member receiving opening therebetween and having an arcuate length thereof sufiicient to encompass a major portion of such a member receivable Within said opening; a plurality of slip bodies supported by said connecting means in arcuately shaped upright relationship thereon, said connecting means extending through and being closely received within openings extending laterally through each of said bodies; said slip bodies having a slip bowl engaging outer portion and an arcuately inwardly facing portion engagable with such a member;

said connecting means being'transversely flexible along at least each portion of the length thereof intermediate said slip bodies to permit said plurality of inwardly facing portions to encompass and uniformly engage such a member.

2. A slip assembly as set forth in claim 1 wherein said connecting means includes means for locking each of said slip bodies in said upright position.

3. A slip assembly as set forth in claim 1 wherein said connecting means includes a plurality of arcuately spaced indexing means for receiving said slip bodies in member engaging upright position, and means cooperable with said indexing means for locking each of said slip bodies in said upright position.

4. A unitary slip assembly comprising: an arcuately shaped connecting means having spaced ends which define a member receiving opening therebetween; a plurality of slip bodies supported by said connecting means in arcuately spaced relationship thereon, said connecting means extending through and being closely received within openings extending laterally through each of said bodies; said slip bodies having a slip bowl engaging outer portion and an arcuately inwardly facing portion engagable with such a member; said connecting means being formed of an elastomeric material having sufficient rigidity to freely support said slip bodies in a substantially upright relative position and being readily deformable to permit said inwardly facing portions to uniformly engage such a member.

5. A unitary slip assembly as set forth in claim 4 wherein said connecting means has an arcuate length thereof sufficient to encompass a major portion of such a member receivable Within said member receiving opening.

6. A slip assembly as set forth in claim 5 wherein said connecting means includes means for locking each of said slip bodies in said upright position.

7. A slip assembly as set forth in claim 5 wherein said connecting means includes a plurality of arcuately spaced indexing means for receiving said slip bodies in member engaging upright position, and means cooperable with said indexing means for locking each of said slip bodies in said upright position.

8. A slip assembly as set forth in claim 5 wherein each of said slip bodies has a first opening adjacent the upper end thereof and extending laterally therethrough, a second opening intermediate the upper and lower end thereof and extending laterally therethrough; and wherein said connecting means include vertically spaced upper and lower arcuately shaped bands which extend through each of said first and second openings, respectively.

9. A slip assembly as set forth in claim 5 wherein said connectnig means includes a first arcuately shaped band having an axially disposed first side and an opposite second side, said first band having a plurality of arcuately spaced notches formed in one of said sides with each of said notches having an arcuate dimension substantially the same as the lateral dimension of each of said openings, for locking said slip bodies on said notches in said upright position.

10. A slip assembly as set forth in claim 9 wherein said slip bodies are snugly received in said notches such that spaces exist between the wall of said openings of said slip bodies and the side of said first band opposite said notches thereof; and wherein means for said locking is a second band having an arcuate shape conforming substantially to that of said first band and sized to be snugly received within said spaces; and including securing means for securing said first band With said second band against arcuate shifting with respect to each other.

11. A slip assembly as set forth in claim 5 wherein said connecting means includes at least one arcuately shaped band having an axially disposed first side and an opposite second .side, and a plurality of arcuately spaced pairs of generally axially opposite grooves extending radially through said band adjacent said sidesthereof; and locking means extending through portions of each of said slip bodies and said grooves for locking said slip bodies in said upright position.

12. A slip assembly as set forth in claim 5 wherein said hinge means includes at least one arcuately shaped band having an axially disposed first side and an opposite second side; and a plurality of arcuately spaced pairs of button means supported by said band member on the inner radial surface thereof, said button means of each of said pair being arcuately spaced from each other for snugly receiving a said slip body therebetween in said upright position.

References Cited UNITED STATES PATENTS 1,730,622 10/1929 OBrien. 1,838,439 12/1931 OBrien. 1,508,661 9/1924 Lignoski.

10 DONALD A. GRIFFIN, Primary Examiner

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