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Publication numberUS2321245 A
Publication typeGrant
Publication dateJun 8, 1943
Filing dateApr 14, 1941
Priority dateApr 14, 1941
Publication numberUS 2321245 A, US 2321245A, US-A-2321245, US2321245 A, US2321245A
InventorsReed John E
Original AssigneeReed John E
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rat-hole swivel wrench
US 2321245 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

June 8, 1943. J. E. REED RAT-HOLE SWIVEL WRENCH Filed April 14, 1941 Patented June 8, 1943 UNITED STATE QFFICE Claims.

This invention is a means and method for making and breaking screw joints between an elevator kelly in a well rig and what is known as a single in a rat-hole in the rig platform.

A single as here used means one section or piece of a drill stem or other well string structure a multiplicity of which singles go to make up the stem or string. Commonly, a stock of singles may lay horizontally on the rig wharf, or stock deck and one single at a time is pulled by a catline to a nearly vertical position over the mouth of a rat-hole which is a hole through the derrick floor and deeply into the ground at a short distance from the well hole being drilled at the rig. The single is then lowered into the rathole and its upper end is suitably held so that the lower end of the kelly can be lowered into juxtaposition with the upper, pin receiving box end of the single and then, usually by means of ropes and tongs, the kelly screw pin is screwed into the box of the single held in the rat-hole. This last performance is tedious and time taking, and requires roping and rope handling; that is, getting out and putting away.

When breaking down a long drill stem or other string, derrick sections, each as long as two or three singles, are unscrewed one after the other and then stood on end in the derrick tower until such time as use of the stands will no longer be needed. Then each section is broken into its component singles so that these can be shifted out of the towe and laid on the wharf to be hauled away or stored.

It is an object of the present invention to provide a means and a method for the expeditious connecting up or the knocking down of singles, of stem or pipe, and to eliminate the usual cat-line or roping in making or breaking the screw joints.

It is an object of the invention to provide a simple, practical, low cost, substantial and highly effective swivel wrench for rat-hole use.

Another object of the invention is to provide a self-feeding wrench, that is, one in which there is a rotary gripping means having an automatic function of feeding one part of the coupling being made up onto the other part.

Further, an object is to provide a unitary power-plant, swivel-function, rat-hole wrench.

And further, an object of the invention is to provide in combination, a rat-holed derrick floor and a swivel, single wrench.

The invention consists in certain advancements in this art as set forth in the ensuing disclosure and having, with the above, additional objects and advantages as hereinafter developed, and

whose constructions, combinations, and details of means and the manner of operation, and the method, will be made manifest in the following description of the herewith illustrative apparatus; it being understood that modifications, variations and adaptations may be resorted to within the scope, principle and spirit of the inven tion as it is more particularly claimed presently.

Figure l is a diagram of a rig having a rat-hole for singles and with which the instant Wrench is combined.

Figure 2 is a plan of the self-powered wrench, engaging an introduced single, shown in crosssection.

Figure 3v is a side elevation and partial axial section of the wrench, in normal empty position of parts.

The derrick floor 2 is provided with the usual central rotary table 3 over the hole being drilled, or finished well, and oil to one side of the table there is shown a slightly inclined pipe or'casing 4 which forms or lines a rat-hole in which a single (drill or other section) S is here disclosed suspended by the wrench B of the present invention.

The wrench includes a suitably shaped basal flange I with a central, bottom face, upwardly converged orifice lip .or guide 8 leading to a barrel 9 of which the base I is a rigid part. I

In the bottom of the barrel is a suitable ball'race ID for a set of balls I I carrying a running race I2 fixed to a superj'acent ring I3 which here forms a worm-gear I I and is fixed to a ring I5 inturned from a running cylinder I5a concentric in the barrel 9. The rim of the barrel has a retainer flange I6 overhanging the cylinder rim to keep the cylinder down.

A series of posts I I is fixed in the ring I5 and each post has a compression spring I8. Supported on the upper ends of the springs is n annular basket I9 with opposite, lateral lugs 24) overhung by the barrel flange I 6 and pressed to it by the set of springs. The basket has a conical bore for the reception of a complementary set of slips 2| whose bore teeth 22 are adapted to bite onto a complementary size drill stem element or other desired element, here called a single, while arranged in the rat-hole. being lowered through the wrench basket I9 the slips are first withdrawn so that the bottom or pin-screw end of the single can be easily stabbed into the rat-hole. The single is then lowered, as by a cat-line, until the upper or box-thread end of the single is just above the wrench basket and then the slips are inserted into the basket to grip the body of the single and hold it suspended in the When a single S is rat-hole; the springs still holding the basket up to the retainer IS.

The slips 2| are here shown as hollow, and

about a half a circle in arcuate length and have free drop-handles 2 la in their tops.

In making up a connection between the lower or pin-screw end of a kelly K, while this is suspended by the rig elevator, the pin end is swung over into alignment with the box end of the wrench supported single S and then the kelly is gradually lowered and the pin is stabbed into the presented box of the single S. The added partial load of the kelly causes the single S and the basket with the slips to recede and press the lugs 20 down in channelways 20a provided therefor in the inner cylinder 15a; the lugs therefore interkey the basket and the cylinder I5a for co-rotation.

The cylinder and its basket may now be rotated either manually or by some prime mover such as a small power plant 25 having a shaft 26 carrying and driving a screw or worm 26 engaging the large drive wheel fixed to the cylinder.

A feature of the invention is that, as the slip basket is rotated while gripping a single S, and has been repressed by the stabbing of the Kelly pin into the box end of the single S, the springs l8 run the box upwardly on the Kelly pin if the rotation of the basket is to the right-hand (looking up) the kelly being held suspended by the elevator. After the joint has been thus made up tongs are applied to the kelly and to the box so that a heavy torque may be applied to the box to clinch up the joint very tightly. The single is then released from the bite of the slips and these are pulled from the basket and the elevator is operated to elevate the now joined single and kelly.

Thus the kelly is never disconnected from the elevator and is itself made of service in the making up of a joint and in pulling the single S from the rat hole and swinging it to the well or hole being drilled. The slip basket is used at the top of the rat hole to suspend the inserted single S and it is used to screw the single to the Kelly pin and no special or secondary elevator or other apparatus is used after the single has once been cat-lined in from the wharf and set in the rathole.

It will be seen from the above how easy it will be to reverse the procedure and quickly break down stands of stem or pipe, racked upright in a tower, into individual pieces so that they may be readily cat-lined out to the wharf.

It has been found by actual practice that a great deal of time has been saved by the tool and method here disclosed in the jointing of singles to make up a drill stem of only a thousand feet in length, and its value in the handling of strings of from five to ten thousands of feet length will be apparent at once.

Compactness, simplicity and low cost of construction and of operation are meritorious features of the swivel wrench of this invention.

What is claimed is:

1. A unitary, well-rig, string joint making and breaking apparatus including a prime motored frame or mount, a swivelled slip basket yieldably supported on said mount, and a drive connection between the motor and the basket for rotating the basket.

2. The apparatus ofclaim 1, the mount having a rotary carrier on which the basket is splined, and a set of springs on the carrier for yieldably supporting the basket whereby to automatically advance the basket in making up a screw joint of string members.

3. A rat-hole swivel wrench, for well drilling operations, including a mount fixable above the rat-hole, a swivelled slip basket yieldably and rotatively supported in the mount for suspending a drill string section in the rat-hole, and power means for rotating the yieldable basket to screw together or to unscrew meeting drill sections.

4. A well drilling tool rat-hole swivel wrench for screwing up or unscrewing threaded joints of drill string sections and which includes a mount fixable above the rat-hole, a slip basket swivelled on the mount to suspend a drill section in the said rat-hole and being cushioned to provide for axial movement as to the mount, and means keyed to the basket and operative to rotate the basket whereby to screw on or to screw off the suspended section as to an upper juxtaposed companion drill string part.

5. A rat-hole wrench, for receiving well drilling tool parts, including a mount fixable in alinement with the rat-hole, a rotary carrier on the mount, a slip basket splined on the carrier for co-rotation therewith, and a spring means whereby the basket is yieldably supported on the carrier for axial shift under the load of an applied drill tool part; whereby as the carrier is rotated a thread joint can be opened or closed as between the tool part in the basket and an upper, adjacent tool part.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2459543 *Jun 14, 1947Jan 18, 1949Gen ElectricBase for an electric device
US2522795 *May 14, 1946Sep 19, 1950Mitchell Roscoe ARat hole digger
US2596774 *Feb 11, 1947May 13, 1952Earle Scheig FritzRathole digger
US2629586 *Jan 28, 1947Feb 24, 1953Harbour Pheron MRathole drilling apparatus
US2633330 *Jun 5, 1948Mar 31, 1953Macco Oil Tool Co IncRotating rathole head
US2661188 *Nov 18, 1949Dec 1, 1953Smoot VanBit lifter and stabber
US3371728 *Oct 18, 1965Mar 5, 1968Global Marine IncKelly stabber
US5255751 *Oct 9, 1992Oct 26, 1993Huey StognerOilfield make-up and breakout tool for top drive drilling systems
US5468121 *Feb 8, 1994Nov 21, 1995Stogner; HueyApparatus and method for positioning drill pipe in a mousehole
US8052370 *Dec 1, 2005Nov 8, 2011Sense Edm AsSystem for handling pipes between a pipe rack and a derrick, and also a device for assembling and disassembling pipe stands
US8245773 *Aug 24, 2007Aug 21, 2012National Oilwell Norway AsCentralizing device for an elongated body in a mouse hole machine
US9303468Nov 2, 2011Apr 5, 2016National Oilwell Varco Norway AsDrilling system and a device for assembling and disassembling pipe stands
US20080304939 *Dec 1, 2005Dec 11, 2008Sense Edm AsSystem for Handling Pipes Between a Pipe Rack and a Derrick, and Also a Device for Assembling and Disassembling Pipe Stands
US20100206562 *Aug 24, 2007Aug 19, 2010National Oilwell Norway AsCentralizing device for an elongated body in a mouse hole machine
U.S. Classification166/77.51, 81/57.18, 173/151, 81/57.24, 175/195
International ClassificationE21B19/16, E21B19/00
Cooperative ClassificationE21B19/16
European ClassificationE21B19/16