US1581442A - Heaving plug for well casings - Google Patents

Description

. K ril 20,1926.

. 135815442 J. L. HAWKINS .nmvms PLUG FI'OR WELL ,CASINGS Filed Jan. 20, 1925 Fig.

Patented A 20 19276. I

. UNITED sr TEs JESSE Louis nawxms; or BAKERSFIELD, CALIFORNIA.

w i g HE AVING PLUG FOB) wEL'LoAsrnGs,

Application filedjanuary 2o,.1e2"5. 'Serial No. 3.63;. L

Toa'ZZ whom it mayomwern 1 H 1 Be it known that I, JESSE LOUIS HAWKINS, a citizen of the United States, residing :at

Bakersfield, in the county of Kern and State of California, have invented certain newand useful Improvements. in Heavmg Plugs for lVVell Casings, of'whichthe following is ,a

specification. I j n a My inventlon relatestodevices commonly known ;in the art as .heavingiplugs7 and which are placed at the bottom of anoil well,-to seal the bottom, of the casing. .The purpose of the plugzisto prevent the gas, present in such wells,.from.forcing or heaving sand or other formation into the bottom of the well and up into the casing. Instances have come under my observation where several hundred feet of sand have been heaved into a well through the failure of the heaving plug.

A heaving plug, to be successful, must not only be capable of easy adjustment to and from engagement in position, but must also be adapted for dislodgment, and removal when it becomes necessary or desirable to redrill the well or to remove the casing.

To provide a plug having these desirable features is the object of my invention, and to this end my invention consists in the novel heaving plug which I shall hereinafter fully describe, it being understood that changes in structure, form and proportion may be made within the scope of the claims hereunto appended without departing from the spirit of the invention.

Referring to the accompanying drawings Fig. 1 is an elevation of my heaving plug.

Fig. 2 is a vertical section of the plug on the line 22 of Fig. 1, showing also in vertical section the application to the mandrel top of the plug of the combination socket of a fishing tool to be used for removing the plug when necessary.

Fig. 3 is a cross section on the line 3-3 of Fig. 1. n

Fig. 4 is a partial section of the plug showing the position of the slips entering the well.

The plug is a light hollow cast-iron shell and comprises a body portion 1, the bottom of which is preferably open, as seen in Fig. 2, and a neck portion or mandrel-like top 2, with closed upper end.

In the shell wall around its circumference, say for example at equidistant points are 4cast intothe plugbo dy. 1 1

a h slip. Danna 3.21 Within theshell backjof each. opening is a wrought iron pin Pivotally mountedupon each is a slip 5. In practice the slip is made from apiece of round steel, and has ageneral segmental shape, withteeth 5? on its arcuate surface, said sIipplaying through the opening 3 and adaptedto engage the casing 12, Fig. 2.

;The slip is also formed-with an abutment surfacejat 5 which coacts with a stop ,6

with which the inner of the shell is provided andwhich serves to limit thefup- .ward and. inward movement of the .slip, as

shown in Fig. 4, when the plug is being lowered in the well casing 12 and is sufliciently retracted to enable it to pass down therein.

The slip is mounted upon its pin by means of a slot 7 at its'inner end, and is held-on the pin by a cotter-pin 8.

It is to be noted that the axis of movement of the slip is eccentric to its toothed surface, and is such that the center of gravity of said slip lies above the horizontal plane of its axis, whereby the projection of the slip to its engagement with the well casing is automatic.

The pins 4 upon which the slips are mounted are, with intention designed to .break out under sufficient arring stress imposed upon the plug. They are strong enough to withstand any pressure to which the plug may be subjected from below, and yet weak enough to shear off or break out of the casting and drop down inside, if the plug be jarred, and thus free the slips and enable the plug to be withdrawn from the well.

In order to thus jar the plug and to remove it, the upper or neck part2 of the plug is made mandrel-like and is formed with a. circumferential series of engaging wickers or ribs 9. This adapts it to be caught by the slips 10 of a combination slip socket 11 of a fishing tool 11, as shown in Fig. 2.

When such engagement is effected and the ing through said openings; and pivotal mountings carried -by and within the shell, one for each slip, said mountings being disruptable under jarring stress imposed upon said shell.

2. A heaving plug for well-casings comprising a hollow shell having openings in its side walls; casing-engaging slips func tioning through said openings; and pins carried by andwithin the shell behind and proximate to said openings, one pin for and pivotally carrying one slip, said pins being mounted and fashioned to break out under jarring stress imposed upon said shell.

3. A heaving plug for well-casings comprising a hollow shell having its lower end open and its upper end closed said upper end being formed mandrel-like to receive the socket of a fishing tool and provided with means for engagement with said socket,

said shell having openings in its side Walls; casing-engaging slips functioning through said openings; and pins carried by and withadapting them for automaticplay through said openings and for limiting abutment against the interior stops of the shell, said pins being fashioned and mounted to break out under jarring stress imposed upon said shell, to release the slips and permit the removal of the plug. r

In testimony whereof I have signed my name to this specification. r

JESSE LOUIS HAWKINS.

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