US3809424A

US3809424A - Adjustable tongs

Info

Publication number: US3809424A
Application number: US00000740A
Authority: US
Inventors: C Crickmer
Original assignee: Individual
Current assignee: Varco International Inc
Priority date: 1968-06-25
Filing date: 1970-01-05
Publication date: 1974-05-07
Anticipated expiration: 1991-05-07

Abstract

Tongs for oil well drilling and tubing operations wherein the tongs are adjustable to engage various sizes of cylindrically shaped members.

Description

United States Patent 1191 Crickmer 1 May 7, 1974 [54] ADJUSTABLE TONGS 1,544,457 6/1925 Jones 294/106 1,787,744 1/1931 Guiberson 81/66 [76] lnvemo Charles BOX 3,316,783 5/1967 Wilson 294/116 134E, Houston, Tex. 97001 [22] Filed: Jan. 5, 1970 FOREIGN PATENTS OR APPLICATIONS 2 Appll 740 647,450 12/1950 Great Britain 81/66,]

Related U.S. Application Data [63] Continuation-impart uf Ser. No. 739,765. June 25, Primary ExaminerEdward A. Sroka 196R, abandoned,

[52] U.S. Cl. 294/113 [51] Int. Cl. 8156c 1/00 [57] ABSTRACT [58] Field of Search 1. 294/113, 116, 106, 119;

24/249 C; 4/156 Tongs for oil well drilling and tubing operations wherein the tongs are adjustable to engage various [56] References Cited sizes of cylindrically shaped members.

UNITED STATES PATENTS 1,077,294 11/1913 O11 M 81/66 8 Claims, 15 Drawing Figures Pmmmm mm 33095424 SHEEI 1 BF 4 INVENTOR 6HARLES 0. GRICKMSR mmmm '1 m4 1809.424

SHEEI 2 OF 4 FIG: 4

9o um as as" I 84 HIINII F/GI 6 INVENTOR CHARLES D. CRICKUER ADJUSTABLE TONGS This application is a continuation in part of application Ser. No. 739,765 filed June 25, 1968, now abandoned.

Presently, tongs are comprised of a plurality of arcuate jaw members hingedly connected together and to a lever arm. The work within the jaw members bears on a plurality of tong dies which are received in the inner surface of the long and short jaws, all as is well known in the art. Since the work diameters vary, all of the tong dies cannot concurrently be in contact with the work, therefore, resulting in shear and moment conditions greater than those for which the tongs were designed. Excessive loading conditions have resulted in failure of tongs and reduced tong die life.

In the present invention, tongs are made adjustable by providing an adjustable hinge means which is adapted to be rotatable in a plurality of positions. With such an adjustable hinge means arrangement, the tongs can conform to various diameter work, thereby minimizing failures lower than the design load and maximizing tong die life. Additionally, the tong of this invention reduces inventory and production overhead for a single tong will perform the function of several tongs of the type presently used in the art.

The objects and advantages of this invention will become more readily apparent to those skilled in the art upon reading of the following detailed description.

Shown in the accompanying drawings are preferred embodiments of the invention in which:

FIG. 1 is a top plan view of a tong constructed according to the principles of this invention;

FIG. 2 is a fragmentary cross sectional view of a first embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 3 is a plan view of a portion of the hinge assembly shown in FIG. 2;

FIG. 4 is a fragmentary cross sectional view of a second embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 5 is a perspective view as showing a portion of the hinge assembly of FIG. 4;

FIG. 6 is a fragmentary cross-sectional view of a third embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 7 is a fragmentary crosssectional view of a fourth embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 8 is a fragmentary perspective view of a fifth embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 9 is a fragmentary plan view, partly broken away to show internal features, of a sixth embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 10 is a partial cross-sectional view taken on line l0l0 of FlG. 8;

FIG. I l is a fragmentary cross sectional view of a seventh embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 12 is a perspective view showing a portion of the hinge assembly of FIG. 11;

FIG. 13 is a fragmentary cross sectional view of an eighth embodiment of a hinge assembly in accordance with the principles of this invention;

FIG. 14 is a perspective view showing a portion of a hinge assembly in FIG. 13; and

FIG. 15 is a fragmentary plan view of a ninth embodiment of a hinge assembly in accordance with the principles of this invention.

FIG. 1 illustrates a tong of the general type used in handling a drill pipe, drill collar, tubing or casing for oil or gas well operations. As is known, such tongs comprise an elongated lever arm 4 having an upper generally arcuate shaped jaw member 6 and a lower generally arcuate shaped jaw member 8 pivotally connected at one end thereof at hinge assembly locations 11 and 18 respectively, and extending outwardly therefrom. The jaw member 8 is pivotally connected to one end of a generally arcuate shaped jaw member 10 at hinge assembly location 20 at the end thereof opposite assembly 18. The free ends of jaw members 6 and 10 carry respective portions of a suitable latching assembly 12 whereby the members 6, 8, and 10 form an opening to receive the member W. As shown, one end portion of latching assembly 12 is detachably fastened to member 10 in any suitable manner and the other end portion of assembly 12 is pivotally connected to member 6 at hinge assembly location 17.

Suitable slots or fastening means are provided in the inside arcuate face of members 6 and 8 to receive a plurality of tong dies 14. The radially inward surfaces of tong dies 14 will bear directly on W when the tong jaw members 6, 8 and 10 are in a latched position.

FIGS. 2 and 3 illustrate a hinge assembly 16 used to pivotally connect lever arm 4 and tong jaw member 6. Jaw member 6 is shown as being of a substantially one piece construction having well known biforcated ends formed by upper and lower spaced

lugs

13 and 15, re spectively, which lugs receive the lever arm 4 therebetween.

Hinge assembly 16 comprises a circular opening 22 in lever arm 4 which has a plurality of radially out wardly extending key ways 24 therein spaced at around the periphery thereof. A bushing 28 having an eccentric through bore 32 therein and a singular radially outwardly extending key portion 26 is slidably and non-rotatably received in the opening 22 and a respective keyway 24 thereof. The centers of opening 22 and bore 32 are respectively indicated at 30 and 34.

In assembly, bushing 28 is fitted into opening 22 in such a way that the keyway 24 cooperates to accept the key 26. Lever arm 4 is then received between

lugs

13 and 15 such that bore 32 is in axial alignment with aligned

bores

33 and 35, which bores 33 and 35 extend vertically through

lugs

13 and 15 respectively. A hinge pin 36 having a diameter thereof substantially equal to the diameter of

bores

32, 33 and 35 is inserted through such bores and the axial length of pin 36 is such that the respective axial ends thereof extend from

bores

33 and 35. Pin 36 is retained in the inserted position thereof by any suitable means, for example, well known snap rings 37.

In operation, member 6 revolves coaxially with respect to the axial centerline of hinge pin 36 thereby defining a definite diameter W which all tong dies 14 can contact concurrently. By removing and revolving bushing 28 until key 26 falls within another keyway 24, the above mentioned member W diameter, which all tong dies 14 can contact concurrently, is changed by an amount determined by a combination of the amount of rotation of bushing 28 from the original position before reinsertion of key 26 in a keyway 24, and the throw of the bushing. The maximum throw of the bushing is equal to twice the distance between

centers

30 and 34. A variety of the above mentioned adjustments can be made, for similar hinge assembly can be provided at

assembly locations

18, and 17.

FIGS. 4 and 5 illustrate another form of a hinge assembly, generally indicated at 80, used to pivotally connect lever arm 4 and tong jaw member 6'. Tong jaw member 6 is of a substantially one piece construction having a single lug portion 82 at the axial ends thereof. As shown, lug portion 82 has a generally flat lower surface which is seatable on the upper surface of of an end portion of lever arm 4. Hinge assembly 80 extends between lug portion 82 and arm 4 for the above mentioned pivotable connection.

Hinge assembly 80 comprises a circular opening 84 in the lever arm 4 which has a plurality of circumferentially spaced radially outwardly extending keyways 85 along the periphery thereof and a radially inwardly extending flange portion 87 at the upper end thereof. A generally cylindrical plug member 86, having a p1urality of radially outwardly extending keys 88 is slidably and non-rotatably received within opening 84. Keys 88 are circumferentially spaced about the outer periphery of plug member 86 such that they engagably cooperate with respective keyways 85. A hinge pin 90 having a diameter thereof less than the diameter of plug member 86 is fixedly secured to the upper surface of plug member 86 intermediate the outer periphery thereof such that the axial centerline thereof is eccentric from the axial centerline of plug member 86.

Lug portion 82 and flange portion 87 have respective

vertical bores

92 and 93 extending therethrough of a diameter substantially equal to the diameter of pin 90. Plug member 86 is inserted upwardly into opening 84 such that keys 88 thereof cooperatively engage respective keyways 85 and pin 90 extends axially through bore 93 and upwardly thereof. Thereafter, bore 92 is aligned with the upwardly extending pin and lug portion 82 is seated on lever arm 4. The axial length of pin 90 is such that upon the above mentioned seating, pin 90 extends through opening 84 and the upper end thereof is spaced upwardly from the upper surface of lug portion 82. Pin 90 and plug member 86 are retained in the above described position by any suitable means, for example, a well known snap ring 37. After snap ring 37 is secured, relative axial movement between lever arm 4 and plug member 82 is prevented by flange portion 87.

The operation of hinge assembly 80 is essentially equivalent to that of hinge assembly 16 as hereinbefore described. The principle difference between the embodiments arises because the respective tong jaw members have differently structured end portions. To this end, it is to be noted that hinge assembly 16 can easily be adapted for use with tong jaw member 6 as those skilled in the art can readily comprehend.

FIG. 6 illustrates a hinge assembly, generally indicated at 100 which is similar to assembly 80 and is used to pivotally connect a lever arm 4 and tong jaw member 6. Hinge assembly 100 comprises a circular opening 102 in lever arm 4 which has a plurality of circumferentially spaced radially outwardly extending keyways 84 along the periphery thereof. A generally cylindrical bushing 104 having an eccentric through bore 106 therein and a plurality of radially outwardly extending keys 88 is slidably and non -rotatably received within opening 102. A hinge pin 108, having a diameter substantially equal to the diameter of bore 106, has the upper end thereof fixedly secured to the lower surface of lug portion 82 and extends downwardly therefrom.

Bushing 104 is fitted into opening 102 such that keys 88 thereof cooperatively engage respective keyways 85. Thereafter, bore 106 is aligned with the downwardly extending pin 108 and lug portion 82 is seated on lever arm 4. The axial length of pin 108 is such that upon the above mentioned seating, pin 108 extends through bore 106 and the lower end thereof is spaced downwardly from the lower surface of the seating portion of lever arm 4. Bushing 104 is retained in the above described position by any suitable means, for example, a well known snap ring 37.

FIG. 7 illustrates a hinge assembly used to pivotally connect a lever arm 4 and tong jaw member 6. Lever arm 4' is shown as being of a substantially one piece construction having a biforcated end formed by upper and lower spaced

lugs

162 and 164, respectively.

Lugs

162 and 164 interfit with

respective lugs

13 and 15 of member 6 such that when lever arm 4' is hingedly connected to jaw member 6 as hereinafter described the lower surface of lug 13 is seated on the upper surface of lug 162 and the lower surface of lug 15 is seated on the upper surface of lug 164.

Inasmuch as each mated pair of lugs as discussed hereinabove must have a separate hinge assembly 160 thereat, the description hereinafter will be directed only to mated

lugs

13 and 162 with the understanding that a similar hinge assembly 160 is provided at the lower mated

lugs

15 and 164.

Hinge assembly 160 comprises a generally circular opening 166 in the lug 164 which has a plurality of circumferentially spaced radially outwardly extending keyways 168 along the periphery thereof. A generally cylindrical plug member 170, which has a plurality of radially outwardly extending keys 172 at an upper portion 174 thereof and a radially outwardly extending flange portion 176 at the lower end thereof has the upper portion 174 slidably and non-rotatably received within opening 166. The outer diameter of flange portion 176 is greater than the diameter of opening 166. Keys 172 are circumferentially spaced about upper portion 174 such that they engagably cooperate with respective keys 168. A hinge pin 178 having a diameter thereof less than the diameter of plug member is fixedly secured to the upper surface of plug member 170 intermediate the outer periphery thereof such that the axial centerline thereof is eccentric from the axial centerline of plug member 170.

Lug 13 has a vertical bore 180 therethrough of a diameter substantially equal to the diameter of hinge pin 178. Pin [78 is received within bore 180 and a snap ring 37 is attached thereto all in a manner similar to that described heretofore with reference to hinge assembly 80. After snap ring 37 is secured, relative axial movement between respective lugs is prevented by flange portion 176.

The operation of hinge assembly 160 is essentially equivalent to that of hinge assembly 80 hereinbefore described. The principle difference between the embodiments arises in the respective flange portions which are used to prevent axial movement between the connected members. To this end it is to be realized that a hinge assembly such as

assembly

80 or 100 can also be be used to pivotally connect the member 6 to a lever arm such as lever arm 4'. Additionally, a hinge assembly 160 can be used to pivotally connect a lever arm 4 to a tong jaw member such as member 6'.

A further feature to be noted with respect to hinge assembly 160 is that although hinge pin 178 is described as having a diameter less than the diameter of plug member 170, it is to be understood that the diameter of such a hinge pin can be greater than the plug member diameter if so desired, as long as eccentricity between the radial centerlines of such members is maintained. It is to be additionally understood that the above specified variation in pin member diameter is equally applicable in other hinge assembly embodiments hereinbefore and hereinafter described which include a plug member having a hinge pin fixedly secured thereto.

FIG. 8 shows a perspective view of another form of a hinge assembly, generally indicated at 43, used to pivotally connect lever arm 4 and tong jaw member 6.

Hinge assembly 43 includes a through bore 49 in the lever arm 4 which slidably receives a bushing receiving member 48 therein. Bore 49 has splines 41 along the peripheral surface thereof such that member 48 is nonrotatably received within bore 49. The bushing receiving member 48 is shaped in the form of an open-ended cylindrical tube which has a plurality of radially outwardly extending keyways 50 circumferentially spaced along the inner periphery thereof and an upper radially outwardly extending flange portion 51. Keyways 50 are splined along the outer periphery thereof to cooperate with splines 41 for the non-rotatable reception of member 48 within bore 49. The diameter of bore 49 is essentially equal to the outside diameter of keyways 50.

A bushing 40 having an eccentric through bore 42 therein and a plurality of radially outwardly extending keys 44 circumferentially spaced about the outer periphery thereof, is slidably and non-rotatably received within receiving member 48. Keys 44 are circumferentially spaced such that they engagably cooperate with respective keyways 50.

In assembly, the bushing receiving chamber 48 is slidably and non-rotatably received within opening 49 so that the bottom surface of flange portion 51 is in contact with the top surface of lever arm 4. The bushing 40 is then slidably received in chambers 48 in such a way that keys 44 thereof are accepted by the keyways 50. Thereafter, arm 4 is pivotally connected to tong jaw member 6 by receipt of a hinge pin through bore 42 in a manner similar to that described with reference to the hereinbefore description of hinge assembly 16.

The operation of hinge pin assembly 43 is essentially equivalent to that of hinge assembly 16 as hereinbefore described. The principle difference being between the embodiments arises in preferential production techniques of the adjustable tong of this invention to those skilled in the art can readily comprehend.

it is to be noted that various modifications can be made to assembly 43 without departing from the inventive concept thereof, for example: assembly 43 is operative without flange portion 51; and bushing receiving member 48 can be cup shaped and having a close lower end thereby allowing an assembly 43 to be used with a tong jaw member such as member 6'.

FIG. 9 and 10 show yet another form of a hinge assembly, generally indicated at 55, constructed in accordance with the principles of this invention and used to pivotally connect lever arm 4 and jaw member 6.

Hinge assembly comprises: a through bore 47 in the lever arm 4 which receives a bushing 54 therein; a transverse step bore 64 which extends, parallel to a tangent drawn to bore 47, from an outer edge of lever arm 4 to a point intermediate thereof where a portion of a side of bore 64 opens into bore 47; and a worm screw 68 which is received within bore 64. Bushing 54 and worm screw 68 are confined within respective bores 47 and 64 by any suitable restraining means such as a snap ring means indicated at 66 for screw 68.

The bushing 54 includes an eccentric through bore 56 which receives a hinge pin therein, such as hinge pin 36, in a manner hereinbefore described with reference to hinge assembly 16, and a centrally located helically toothed worm gear portion around the outer periphery thereof. Worm screw 68 includes a diametrically extending adjusting groove 72 or the like at one end thereof, and a worm portion at the other end thereof.

After assembly, the worm portion 70 engages the worm gear portion 60 in such a way that with the use of a suitable tool in conjunction with the groove 72, revolving of the worm screw 68 causes the bushing 54 to revolve about the central axis thereof, all in a manner well known in the art.

By use of the worm screw 22 arrangement in engagement with worm gear portion 60 of the bushing 54, an infinitely variable adjustment, within the limitations of the throw of the bushing as hereinbefore defined with reference to hinge assembly 16, of hinge assembly 55 is provided.

The operation of hinge assembly 55 is essentially equivalent to that of binge assembly 16 as hereinbefore described with the exception that adjustments can be made by use of the worm screw 72, to provide for various diameter work without the need for disassembling of the tong, and the number of variable adjustments is not defined by the number of keys and cooperating keyways as is the case with assembly 16, but rather the adjustment is infinitely variable, as indicated immediately above.

It is to be noted that although hinge assembly 55 is described for use with reference to a tong jaw member such as jaw member 6, such assembly 55 can be used with a tong jaw member 6' by modifying the assembly in a manner such as illustrated with reference to the description of hinge assemblies and 100.

FIGS. 11 and 12 illustrate yet another form of a hinge assembly, generally indicated at 110, used to pivotally connect lever arm 4 and tong jaw member 6". Jaw member 6" is shown as being of a substantially one piece construction having well known biforcated ends formed by upper and lower spaced lugs 13 and 15', respectively, which lugs receive the lever arm 4 therebetween.

Hinge assembly 110 comprises a circular opening 112 in the lever arm 4 which has a plurality of circumferentially spaced radially outwardly extending keyways along the periphery thereof. A generally cylindrical plug member 114 having a plurality of radially outwardly extending keys 88, is slidably and nonrotatably received within opening 112. Keys 88 are circumferentially spaced about the outer periphery of plug member 114 such that they engagably cooperate with respective keyways 85. Plug member 114 additionally includes a pair of axially aligned spaced blind bores 116 and 118 therein which are respectively open at the upper and lower surfaces of plug member 114. The radial centerline of

blind bores

116 and 118 is eccentric with respect to the radial centerline of plug member 114.

In assembly, plug member 114 is fitted into opening 112 in such a way that keys 88 cooperatively engage keyways 85. Lever arm 4 is then received between lugs 13' and 15' such that blind bores 116 and 118 are in axial alignment with aligned bores 120 and 122, which bores 120 and 122 extend vertically through lugs 13' and 15', respectively, and are threaded along the internal periphery thereof. Suitable dog pointed screws 124 are then threadably received within bores 120 and 122 until a generally circular cross section, unthreaded portion 126 thereof is cooperatively rotatably received by respective blind bores 116 and 118. The diameter of

blind bores

116 and 118 is essentially equal to the diameter of portion 126.

In operation, member 6" revolves coaxially with respect to the radial centerline of

blind bores

116 and 118 thereby defining a definite diameter W which all tong dies 14 can contact concurrently. By removing and revolving plug member 114 until keys 88 fall within other keyways 85, the above mentioned member W diameter, which all tong dies 14 can contact concurrently, is changed by an amount determined by a combination of the rotation of plug member 114 from the original position before reinsertion thereof into opening 112, and the throw of the plug member 114. The maximum throw of plug member 114 is equal to two times the eccentricity between the radial centerline of plug member 114 and the radial centerline of

blind bores

116 and 118.

FIGS. 13 and 14, illustrate another form of a hinge assembly generally indicated at 130, used to pivotally connect lever arm 4 and tong jaw member 6". Jaw member 6" is shown as being constructed of substantially identical elongated arcuate upper and lower

tong jaw portions

132 and 134 respectively.

Portions

132 and 134 are releasably connected into the unitized tong jaw member 6" in any suitable manner for example bolt means 136 which are suitably positioned along the arcuate length thereof.

Portions

132 and 134 have respective substantially

identical lugs

138 and 140 at the ends thereof such that when

portions

132 and 134 are mated to form tong jaw member 6", the

lugs

138 and 140 form a bifurcated end which receives the lever arm 4 therebetween.

Hinge assembly 130 comprises a circular opening 142 in the lever arm 4 which has a plurality of circumferentially spaced radially outwardly extending keyways 144 along the periphery thereof. A generally cylindrical plug member 146, having a plurality of radially outwardly extending keys 148 is slidably and nonrotatably received within opening 142. Keys 148 are circumferentialy spaced about the outer periphery of plug member 146 such that they engagably cooperate with respective keyways 144. Upper and lower axially aligned hinge pins 150 and 152, respectively, which have a diameter thereof less than the diameter of plug member 146, are fixedly secured to the upper and lower surface, respectively, of plug member 146 intermediate the outer periphery thereof such that the axial centerline of such aligned hinge pins is eccentric from the axial centerline of plug member 146.

Lugs

138 and 140 have

vertical bores

154 and 156, respectively, extending therethrough of a diameter substantially equal to the diameter of hinge pins 150 and 152. Plug member 146 is inserted into opening 142 such that keys 148 thereof cooperatively engage respective keyways 144. Thereafter, bores 154 and 156 are aligned with respective vertically extending hinge pins 150 and 152 such that upon joining

jaw portions

132 and 134 to form jaw member 6", pins 150 and 152 are slidably and rotatably received within

bores

154 and 156, respectively.

The operation of hinge assembly 130 is essentially equivalent to that of hinge assembly 16 as hereinbefore described. The principle difference between the embodiments arises in the two piece unitized construction of tong jaw member 6" which allows the use of a plug member which has the hinge pins fixedly secured thereto. It is to be noted that by following the teachings of assembly 130, various modifications can be made thereto by those skilled in the art, for example: the hinge pins can be fixedly secured to the respective inner surfaces of the

lugs

138 and 140 and be slidably and rotatably received within an eccentric bore in plug member 146; or bores 154 and 156 can be blind bores rather than through bores and still be capable of receiving respective hinge pins therein.

FIG. 15 shows another form ofa hinge assembly, generally indicated at 75, used to pivotally connect lever arm 4 and tong jaw member 6.

Hinge assembly includes a hexagonal crosssectional shaped opening 76 in lever arm 4 which slidably and nonrotatably receives a hexagonal crosssectional shaped bushing 77 therein. Bushing 77 has an eccentric through bore 79 therein. Bore 79 slidably and rotatably receives a hinge pin 36 therein in a manner hereinbefore described with reference to hinge assembly 16.

The operation of hinge assembly 75 is essentially equivalent to that of hinge assembly 16 as hereinbefore described. The principle difference between the embodiments rises in the adjustment means, that is, in assembly 16 the adjustment is by revolving a key into different keyways, but in assembly 75 the adjustment is by revolving the bushing 77 through one or more flats. it is to be additionally noted that although a hexagonal cross-section is shown with respect to opening 76 and bushing 77 other cross-sectional configurations are equally applicable, for example; square, octagonal, triangular and the like. Furthermore such polygonal cross-sectional configurations can equally be used with other hinge assembly embodiments hereinbefore described.

The

hinge assembly embodiments

16, 80, 100, 43, 160, 55, and heretofore described in detail can be used exclusively or in conjunction with each other at the

hinge locations

11, 17, 18 and 20 indicated in P16. 1. Additionally, more or less hinges can be provided as conditions dictate.

It is to be noted that the invention herein resides in having an adjustable hinge assembly through the use of an eccentric hinge pin type arrangement with a bushing or plug member and accordingly, one skilled in the art can make alterations in the preferred embodiments illustrated herebefore without departing from the scope of the invention. The description herein does not limit the structure of the invention and the invention is defined by the scope of the claims set forth hereinafter.

What is claimed is:

l. A tong for grasping an elongated object comprising; a plurality of serially connected members, with two of said members having unconnected ends, for encircling such an object; latching means for releasably connecting said two members; at least one of said members having an opening therein; an insert non-rotatably and removably received within said opening in any one of more than two operative positions said insert having a central axis coincident with the central axis of said opening, elongated hinge pin means pivotally connecting said one of said members with another of said members, said hinge pin means extending outwardly of said insert with the central axis thereof being parallel to and eccentric to said, central axis of said insert.

2. A tong as specified in claim 1 wherein said one of said members has a single end portion where said opening is located and said another of said members has a bifurcated portion to embrace said single end portion.

3. A tong as specified in claim 1 wherein said opening has a plurality of axially extending radial keyways and said insert has at least one key portion mating with any one of said keyways.

4. A tong as specified in claim 3 wherein said insert has a number of key portions equal to said plurality of keyways.

5. A tong as specified in claim 1 wherein the outer periphery of said insert mates with the entire inner periphery of said opening.

6. A tong as specified in claim 1 wherein said hinge pin means comprises axial extension portions carried by said insert.

7. A tong as specified in claim 1 wherein the connections of said members are pivotal about axes parallel to a central axis of said elongated object.

8. A tong as specified in claim 1 including a bore extending through said insert with the central axis of said bore being parallel to and eccentric with respect to the central axis of said insert and with at least a portion of said hinge pin means being received within said bore. l l t l i

Claims

1. A tong for grasping an elongated object comprising; a plurality of serially connected members, with two of said members having uncOnnected ends, for encircling such an object; latching means for releasably connecting said two members; at least one of said members having an opening therein; an insert non-rotatably and removably received within said opening in any one of more than two operative positions said insert having a central axis coincident with the central axis of said opening, elongated hinge pin means pivotally connecting said one of said members with another of said members, said hinge pin means extending outwardly of said insert with the central axis thereof being parallel to and eccentric to said, central axis of said insert.

8. A tong as specified in claim 1 including a bore extending through said insert with the central axis of said bore being parallel to and eccentric with respect to the central axis of said insert and with at least a portion of said hinge pin means being received within said bore.