US1552062A - Clamping device - Google Patents

Description

Sept. 1 1925..vv

G KRELL cLAMr-I'Ne DEVICE Filed Nov. 28, 1924 6... .v r '60 7 I Patented Sept. 1, 1925.

Gannon or 'saruLI-A, oxmnoma.

OLAMPING' DEVICE.

.- Application filed November 28, '1924. Serial No. 752,648.

To all when it comm: 4

Be itknown that I, Gronon KRELL, a citizen of Germany, residing at SapuIpa, in

the county of Greek and State of Oklahoma, have invented certain new and useful Improvements in Clamping Devices; and I do declare the following to be a full, clear,

and exact description of the invention, such as will enable others skilled in the art, to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marlied thereon, which form a part of this specification.

This invention relates to clamping devices ,for pipe and the clamping mechanism has been especially designed for use in con-nection with evices used in the oil fields for drilling wells. For example, elevators for casings, sucker rods and the like, spiders for the casing and those devices are commonly known as clamps. All-employ some form of jaw for gripping the pipe or sucker rod and in this respect there is an analogy between all three, but the construction of the-supporting means or frame for the jaws in the elevator, the spider and the ordinaryv clamp diflers.

Therefore I would have it understood that in so Far as the generic application of the jaws and their operating means'is concerned, my invention contem plates the inclusion of-such mechanism in any form of clamp but specifically the supporting means illustrated inthe drawings is adapted for a spider. Hence in the claims the word clamping device is intended to be generic to any for of clamp.

The novel construction 0 the preferred embodiment of my invention will be clearly understood by reference to the following description in connection with the accompanying drawings, in which Fig. 1 is a perspective view of a spider embodying my invention with the jaws in open position.

Fig. 2 1s a vertical sectional view through the spider showing the jaws in clamping position.

Fig. 3 is a perspective view of a spider viewed from the side opposite to that shown in Fig. 1.

Fig. 4: is a plan view of the spider, and F ig. 5 is a fragmentary sectional view through one of the slips.

The base frame 1 is shown as substan-' tially rectangular with a slot 2 in one wall be inspected or re aired and .by means of which the frame can be moved into and out of position with respect to the pipe 3. The sidewall '4 of the frame 1 is provided with a recess 5 to provide clearance for the toggle levers which operate-the aw member. These toggle levers willbe described in detail hereinafter.

Theframe 1 carries two'sets 6 and 7 of upstanding bearing lugs, one set at each.

end. The lugs constitute bearings for the rock shafts 8 and 9 which support the rocker arms 10, 11, 12 and 13 rigidly fastened to the rock shafts by set screws 14. The purpose of providing the set screws so that the rocker arms will be fast to the rock shafts is and '16 provided with trunnions 17 and 18 mounted in the inner ends of the rocker arms.

The jaw members 15.and1 6 are pivoted in the rocker arm's below their transverse centers only so that the upper ends of-the jaw.

members will tend to spread apart, due to the fact that the center of gravity of each aw member is above the transverse center of the aw member. ThlS 1s impossible where there are pivotal connections for the jaws 15- I above-the transverse centers. The purpose of .so mounting the jaw member is to cause the lowermost teeth 19. and 200i the slips 21 and 22 to firmly grip the article clamp'd,"-

for example the pipe 3. Therefore if-the lower teeth become worn, the next s'ucceeding teeth will be sharp enough to 'I'obtain the .nccessary grip on'the pipe. Theslips 21 and 22 are shown as provided with transform of segments. They are removably fastened to the jaw members'i15 and 16' by bolts 24am]- 25, -The slips are removable for two purposes, first so that the sli s can cause slips having aces-cuton diflierntarcs can be introduced in the same jaws fbntaking care of various sizes-ofpipe..'

The ends of the aw members. an'd16 verse teeth 19 and 20, the slips beingin the 9 are beveled or flared outwardly 'as indicated at 26, 27, '28 and 29,*sothat theends of. the pipe will be properlyguided'between the jaws. The inner walls of the slipsvin' the jaw members'are also beveled as at 30 and 31, to permit the coupling on pipe 3 to pass through the jaws as the pipe is being removed. The jaws are maintainedfin subbeing desirable that the jaws firmly eng of clamp,

stantially effective parallelism by the rod 33 which passes through the ear 34 on jaw 15 and through the rear 35 on jaw 16, it age the pipe 3 to hold it suspended in the well, and since the teeth 19 and 20 for the slips 21 and 22 are arranged in horizontal planes, it will be ap arent that tendency of the pipe to slip ong'rtudinally will be eliminated. These teeth under all conditions will not be effective in preventing turnin of the pi e about its axis so the pipe will ave a ten ency to slip when a wrench is used to connect or disconnect the pipe sections. In order to overcome the tendency of' the pipe rods or the like to turn about its axis, I provide dies or inserts 36 and 36' which are provided with vertical or longitudinal teeth 37, the teeth of the insert projecting inwardly sli htly beyond the teeth 19 so that they wil grip the article to be clamped in a manner firm enough to prevent the article from turning about its axis. This is quite an important feature in any'form particularly those used in the oil fields. The main purpose of insetting I the teeth 37 with respect to the teeth 19 is as comprising a lever 38 that, when the jaws take hold of the pipe, the teeth 37 will sink intJo the pipe just enough in excess of the teeth 19 to hold the against turnin when a wrench is applied to the next'lughest pipe section. If both sets of teeth were coincident at their outer edges and a wrench was used to turn the next highest pi e section, the teeth 37 would tend to 1111 ofi or at least fail to hold as efiicientl y as with the arrangement described.

Inasmuch as the'jaws 15 and 16 have considerable weight, it is essential that some form of jaw openingmechanism be provided which may be conveniently operated with little power to spread the jaws apart, itbeing understood that the jaws always have a tendency to swing into clamping position due to the fact that they are supported above the rock shafts 8 and 9.

The jaw opening mechanism is illustrated pivoted to a lug 39 on the frame 1, the lug 39 having a stop projection 39' for the lever 38. Movable longitudinally in the uide lugs 40 and 40 on the lever 38 is a og 42 which is nor mally urged into engagement with a recess 41 in lug 39 by an expansion spring 42', one end of which bears against lug 40 and the other against the pin 44. The dog can be moved out of engagement with any one of the openings 41 by a hand lever 45 pivoted to the lever 38 at 45 and connected to the dog by a link v46.

The lever 38 is fast to a rocking stub shaft 47 in the lug 39, the inner end of the rocking stub shaft carrying an arm .48 which is pivoted to the two toggle levers 50 and 51- in eagues turn connected to the trunnions of the jaw members 15 and 16. The inner ends of these levers may be received in the recess 5 when the jaws are in clamping position, the recess 5 being merely a clearance for the ends of the levers. It will be impossible to operate the lever 38 in such a manner that the pivotal connection 52 will be above a horizontal plane passin through the trunnions, because before t at can occur, the lug 40 will contact with the stop 39". Therefore the jaws will always have a ten dency to seat themselves or drop into pipe or rod clamping position. When lever 38 is swung in either direction, shaft 47 rocks swinging arm 48 fast to it. The arm 48 imparts movements to the to 'gle links 50 and 51 which in turn rock liifirs 10,-11, 12 and 13 fast to the rock shafts 8 and 9 so that the shafts 8 and 9 rock in their re spective bearings.

Since one side of with a slit or slot 2, that side of the casting is braced by a tie rod or brace rod 54 connected to the rock shafts 8 and 9. The ends of the frame 1 are provided with outstanding projections 55 and 56 which carry links 57 and 58 whereby the frame may be connectedto a hoist to move it into and out of functional position. provided with depending lugs 60, one at each corner, each lug being provided with a set screw 61, by means of which the frame may be fastened to a support where the clamp is incorporated in a spider.

In actual practice I prefer to have the links 10, 11, 12 and 13 on an les of. about 65 from the horizontal, as I nd that this angle of inclination for the links,insures an adequate gripping surface for the jaws and any lesser angle seems to lessen the gripping efliciency of the jaws. -Obviously however, I do not wish to be limited to this particular angle.

When the parts are assembled and it is desired to use the invention as a spider, the frame maybe clamped to its support, for examplefto the casing head 62. Then the pipe is lowered by theelevator 'to the desired depth, the spread jaws are adapted to seat themselves against the pipe and swing down to seating position to hold the pipe while a new section of pipe or casing is screwed on as is Well understood, then the lever 38 will be operated to spread the jaws apart so that the pipe may be lowered a sufficient distance to allow a new section of pipe to be screwed on and so on until the desired length of string of pipe is provided. The position of the pivot point 52 is important because I have found that by pivoting the toggle lovers 50 and 51 and the arm 48 at a point coinciding with the plane passing through the axis of the opening in the frame that the jaws can be opened with relatively little The frame is also the frame is provided February 27,

' of ,the bolts they can slips is that the bolts pass are below the longitudinal center the center of the frame.

other words power and that each jaw will tend to move substantially the same distance away from Thus the jaws can be opened with grcaterfacility than if the arm 48 was pivoted to one of the links 50 and 51 to one side of the center line of the frame.

When it is desired to remove the spider the bar 54 may be removed, then the spider can be slipped to one sidebecause the slot 2 is wide enough to permit the largest sized pipe to pass through it.

In m former Patent #1,446,568, dated 1923 for an elevator, I have shown a certain form of jaw mechanism which has certain advantages in an elevator but since filing the application for that patent, I have developed the improvements in jaw mechanism enumerated in this application and I find by actual practice that the same form of jaw mechanism illustrated in this application and the same form of jaw spreading mechanism illustrated in this application is better adapted for the elevator than the mechanism shown in said patent. Therefore I recommend the jaw mechanism shown in this application and the jaw spreader shown in this application as a better form to be used in connection with an elevator. Practical experience has shown that if the fastening devices used for securing the slips in the aws are insertable from the inner sides of the jaws and slips and do not pass through the jaws, difficulty is encountered in removing the fastening devicesavhen the slips are to be changed. This is due to the fact that salt water causes corrosion about the fastenin devices so that they freeze. Therefore I ma e the bolts 24 and 25 long enough to passthrough the slips and through the jaw me bers' and hold them by nuts 24 and 25. This allows the fastening devices to be manipulated from the outside when it is desired to take out the slips. In

the nuts 24: and 25 can be reon the threaded ends e loosened as the salt water does not affect the outside nuts. Even if it should the nutsare more accessible than the inner ends of the bolts. 7

Another feature in connection with the holes through which the moved and by tappin of the slips and of the jaws. The main purpose of this construction'is to prevent the slips getting in upside down. the arrangement shown it will be impossible to put the slips in incorrectlybecause the holes in .the slips must match withthe holes in the jaw members.

Attention'is also'calle'd to the fact that there is a marked advantage in havingthe top end of the jaws swung outwardly when the pipe is-about to be engaged by the jaws. The advantage is this ;v the lower teeth of the central opening in the slips first take hold and then the remaining teeth. Therefore the lowermost teeth take the shock and as they wear away the next higher teeth, still sharp, take the shock so that the teeth of the slips wear away progressively from the bottoms. of the jaws to the tops instead of all the teeth wear ing away simultaneouslyf According to my invention then there will always be sharp teeth on the slips until they have all worn off iprogressively from the bottom ends upward. I

The location of the lever 38 with the arm 48 for operating the jaws is an important part of this invention, because the aws 15 and 16 are quite heavy so that the leverage ratio must be considerable tospread them apart Therefore by locating ,the pivot point of the lever 38 between the shafts 8 and 9, the necessary leverage can be'obtained for opening the jaws.

Where the lever is mounted in actual alignment with one of the rock shafts 8 or 9 or outside the rock shafts 8 or 9, an excessively long lever 38 is necessary so long indeed as to make the inclusion of a lever almost rohibitory. Particularly is this true w ere the mechanism is used in connection with an elevator, for it should be borne in mind that attention must be aid toclose clear'- 3 ances for the walking beam and the like i when the tubing is being pulled.

Inasmuch as different (hametersof pi" are used it is desirable to have the slips and 22 removable. A set of sli s cani-hp'; made to be used in a single set 0 jaws for varying diameters of pipe. sist of a number of pairs of slips, all the pairs having the same are or curve oil-their outer faces but the inner faces of each pair will differ as to are or curve, the are being that which will best suffice' for a articular diameter of pipe. Therefore if t e device is used for a 10-inch pipe and it is desirable to operate on 8-inch'or 6-inch pipe, it will; only necessary to remove the 10-inch slipsa substitute the 8-inch or 6-inch slipsjnd course this also ap lies to slips or other... diameters of pipe. he substitution dfthe 1- interchangeable slips for those already in thejaws can be quickly and expeditiously made by taking out the bolts 24: and 251th;- moving the slipsand substituting other Y It will be observed that the jaws are pro- 1 9 vided with recesses receive the slips so thatwhen the nuts on the bolts 24 and 25 are tightened, the slips will be securely held I in place, the edges of the recessesin" the aws supporting the weight. 1

Attention is also called to the fact that the. base or frame 1 is of less diameter than the spac between the jaws when the jaws are opened, thus the central opening for thepipe 2: will eon 1 stitute a guidg for guiding the pipe intoproper positidrgto be embraded the jaws. What I cla m and desire to secure by Letters-Patent is 9- 1, A clamping device comprising a sup- 7 port, rocking aw-c'arrying'members on the support, andjcomplementary jaws carried by the rockmgmembers, movable one toward the other forblampin an object between them, the jaws being jplvoted to the rocking members below their transverse centers only,

so that the upper-ends of the complementary jaws will tendto spread apart.

"2. A clamping device comprising asapp0rt,rockin jawcarrying members on'the support an complementary jawscarried by the rocl rfing members, movable one toward the other for clamping an object between them, the jaws being pivoted to the rocking being effective in spreading them.

members below their transverse centers only, so that the upper ends of the complementary jaws will tend to spread apart, and means for spreading said jaws. V

3. A clamping device comprising a support, rocking jaw-carrying members on the support, complementary jaws carried by the rocking members, movable one toward the other for clamping an object between them, the jaws being pivoted below their trans verse centers only, so that the upper ends of the complementary jaws will tend to spread apart, and means for opposing the tendency of the jaws to move together, said means 4. A clamping device comprising a frame, rocking aw-carrying members on the frame, and two diametrically opposite complementary clamping jaws carried by the rocking members, the jaws being pivoted below their transverse centers only, so that the upper ends of the complementary jaws tend to spread apart, and means for spreading said aws.

5. A clamping device comprising a frame, rocking j aw-carrying members on the frame, two diametrically opposite clamping jaws carried by the rocking members, the jaws being pivoted below their transverse centers only, so that the upper ends of the complementary jaws tend to spread apart, means for operating said jaws and means carried by the jaws to prevent the article clamped from turning with respect to the jaws, said means comprising lateral teeth and longi tudinal teeth. one 'set of teeth extending inwardly slightly beyond the other set of teeth. (5. A clamping device comprising aframe, two diametrically opposite clamping jaws carried by the frame, the jaws being pivoted below their transverse centers only so that the upper ends of the complementary jaws with respect to the jaws, said means comends of the prising lateral teeth and longitudinal teeth, one set of teeth extending inwardly slightly beyond the other set of teeth. i

7. A clampin device comprising a frame, two diametrica ly opposite complementary clamping jaws carried by the frame, the j aws being pivoted below their transverse centers only so that the upper ends of the comple mcntary jaws will tend to spread apart, means for operating said jaws and means carried by the jaws to prevent the article clamped from turning with respect to the jaws, said means comprising lateral. teeth and longitudinal teeth, the longitudinal teethextending inwardly slightly. beyond the other set of teeth.

8. A clamping device comprising a frame, rocking jaw-carrying members on the frame, two diametrically opposite complementary clamping jaws carried by the rocking members, the jaws being pivoted below their transverse centers only, so that the upper complementary jaws will tend to spread apart and means for operating said jaws, the jaws having outwardly beveled top and bottom edges.

9. A clamping device comprising a frame, rocking jaw-carrying members on the frame, two diametrically opposite complementary clamping jaws carried by the rocking membcl's, the jaws being pivoted below their transverse centers only, so that the upper ends of the complementary jaws will tend to spread apart, meansfor operating said" jaws, lugs on the frame and adjustable fastoning devices in the lugs to rigidly secure the clamping device to a support.

10. A clamping device comprising a frame, parallel rock shafts carried by the frame, complementary clamping jaws having supports rigidly secured to the rock shafts, the jaws being movable toward and away one from the other and means for spreading said jaws apart. v

11. A clamping devicecomprising a frame, two parallel rock shafts carried by the frame, jaws having supports rigidly mounted on the rock shafts and having swinging movement toward and awayfrom the center of the frame, the ends of the jaws being beveled outwardly, means in the jaws for preventing the article clamped from turn.- ing, said means comprising lateral teeth and longitudinal teeth, one set of teeth extending inwardl slightl beyond the other set of teeth an means for spreading the jaws.

12. A clamping device comprising a frame, two parallel rock shafts carried by the frame, jaws having supports rigidly mounted on the rock shafts and having swinging movement toward and awa from the center of the frame, the ends 0 the jaws being beveled outwardly, means in the jaws for preventing the pipe from turning, said means comprising lateral teeth and longitudinal teeth, one set of teeth extending inwardly slightly beyond the other set of teeth, means for spreading the jaws, and securing means carried by'the respective corners of the frame.

13. i A clamping device comprising a frame, two parallel rock shaft-s carried by the frame, jaws having supports rigidly mounted on the rock shafts and having swi igi ing.-

movement toward and away from the center of the frame, the ends of the. aws being beveled outwardly, means in'the ]i1WS'l'Ol reventin the article clam ed from turning, said means comprising lateral teeth and longitudinal teeth, one set of teeth extending inwardly slightly beyond the other set of teeth, means for spreading the jaws, and clamping device securing means carried by the respective corners of the frame, said means comprising set screws.

14. A clamping device comprising a frame, complementary jaws carried by the frame. the jaws being pivoted below their transverse centers, apair of toggle. levers connected one to the otherand at their ends to the jaws, and an operating lever pivoted to the frame and connected to the, toggle levers slightly to one side of a plane pass-- ing through the axis of the opening described by the aws when the aws are in clampingposition.

15. A slip for removable attachment to a recessed clamp jaw of an oil well casing spider and the like, comprising a substantially rectangular body having transverseteeth, and a removable insert having vertical teeth, the vertical teeth of the insert extend in g slightly beyond the horizontal teeth.

16. A slip for removable attachment to a recessed clamp jaw of an oil well casing spider and the like, comprising a substantially rectangular body having transverse teeth, and a removable insert having vertical teeth. the vertical teeth of the insert extending slightly beyond the horizontal teeth, the insert being receivable in the upper edge of the body.

17. A slip for removable attachment to av recessed clamp jaw of an oil well casing spider and the like. comprising asubstantially rectangular body having transverse teeth. and a removable'insert having vertical teeth, the vertical teeth of the insert extending slightly beyond the horizontal. teeth. the insert being receivable in'the upper edge of the body, the slip having an offset opening below its transverse center to receive a bolt passing through the jaw so that when the offset opening in the slip cw incides with the bolt the insert must be at the top of the slip.

18. A slip for'rernovable attachment to a recessed clamp jaw of an oil well casing spider and the like. comprising two members, one a main body member and the other an insert therefor, one of the members having horizontal teeth and the other vertical teeth, the teeth of one member project.- i ng slightly beyond the teeth of the other.

19. A clampingdevice, comprising-a1 support, jaw carrying rocker arms pivoted to j the support, complementary jaws pivoted to the: rocker arms below their transverse centers only, jaw operating means comprising a lever pivoted tothe support between the pivots ol the rocker arms, and operating connections between the lever and the jaws.

20A clamping device comprising a sup.

port, shafts at opposite ends of the support,

rocker arms on the shafts, jaws carried by the rocker arms, the jaws being pivoted to the rocker arms below their transverse centers only, jaw operating means comprising links connccted one to the other and to the complementary jaws. and a lever connected to the links, the lever being mounted be tween the shafts. 1

21. A slip for removable attachment to a recessed clamp jaw of an oil well casing spider and the like, comprising two memhers. one a main body member and the other an insert therefor, horizontal teeth on the main body member and vertical teeth on the insert, the vertical teeth extending inwardly, slightly beyond the horizontal teeth of the main body n'iember.

A clamping device comprising a supporthaving rocking members, complementary jaws, movable one toward the other for clamping an object between them, the jaws being pivoted to tlnrroclting members below their transverse centers only, and to one side ol :1 vertical plane passing through the jaws so that the upper ends of the jaws will tend to spread apart. 23. clamping device r-oniprisir a support having rocking members. CfUlIlPlBDNl'P' tary jaws, movable onetoward the other for clamping an object between them, the jaws being pivoted to the rocking members below their transverse centers only. and to one side of a vcrtical plane passing through the aws aws being pivoted to the rocking members In testimony whereof I afiix my signature. I

GEORGE KRELL.

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