US1582184A

US1582184A - Method and means for perforating well casings

Info

Publication number: US1582184A
Application number: US696454A
Authority: US
Inventors: Sidney W Mims
Original assignee: Individual
Current assignee: Individual
Priority date: 1924-03-03
Filing date: 1924-03-03
Publication date: 1926-04-27
Anticipated expiration: 1943-04-27

Description

April 27,1926. '1 1 1,582,184

S. W. MIMS METHOD AND MEANS FOR PERFORATING WELL CASINGS Filed March 3, 1924 Patented Apr. 27, 1926. i

UNITED STATS `SIDNEY W. m8, 0F LOS ANGELES, CALIFORNIA.

METHOD AND `MEANS FOR PEREORATING WELL CASTINGS.

Application led March 3, 1924.v Serial No. 696,454.

lTo all 'whom it may concern.'

Be it known that I, SIDNEY W. MIMS, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Method and Means for Perforating Well Casings, of which the fol lowing is a specification.

This invention'relates to a method and means for perforating well casing and refers particularly to a method and means for perforating well casing in place in a well hole.

'In the construction and operation of oil Wells ila-frequently becomes necessary to perforate a pipe or casing in place in the well hole and disposed' at a considerable distance from the top of the well hole. The art has found considerable diiiculty in properly opening such well casing or pipe. One example of the necessity of opening such holes is encountered where a. casing has been cemented in a well hole for the purpose of shutting olf the water from the oil sand and it is then found that the shut oif of water is not complete and it is desired to open the casing at another point to permit further cement to be forced behind the well casing so as to complete the shut ofi'. Moreover, in certain oil fields the oil wells have been originally drilled to upper oil sand which at the start of the history of the oil field produced less oil than the lower oil sand and accordingly a great number of wells have been drilled through the first oil sand, the well pipe then cemented to close .u p the well formation, and the well .then bored below such upper oil sand into the lower oil sand with an additional casin employed for reaching to the lower oil san As the lower sand becomes exhausted it is desirable to again open the well into the .upper oil sand, and' for this purpose it is necessary to perforate both well casings at the same time.

An object of this invention. is'to provide an improved device forperforating well casings and to provide such va device as will form a clean hole through the well pipe leaving the pipe or casing undamaged and strong around the perforations and to provide such a method and means as can be used to perforate even double the wall cas. ing in place in a deep well.,

Other objects and advantages of the inventionwill be' apparent from the description of the invention in its preferred form or embodiment.

Reference `is therefore had to the accompanying drawings, which illustrate a device whichma be .used to carry out my preferred method ofperforating a well pipe or casing in place in` an oil well.

Figure 1 is an elevation in vertical section through a well hole disclosing the manner of perforating a well pipe or casing in order to re-cement the well.

Fig. 2 is an enlarged elevation mainly in vertical section ofthe body of the perforating device shown in- Fig. 1.

Fig. 3 is an end elevation of a modified form of thel device.

Fig. 4 is an elevation at right angles to Fig. 3 and mainly in vertical section.

ig. 5 discloses another sectional view of a well hole in this case `illustrating the double wall casing which may be perforated by the deviceand method of a further modifcation of this invention.

Fig. 6 is an enlarged view of this further modification of the perforating device mainly in vertical section.

Referring first to Fig. 1, the 1 indicates a well casing or pipe in place in a well hole, which pipe has 'previously been cemented so that cement indicated at 2 lies outside of the well casing 1, between the casing and the formation 3. In such a Well hole the small passages such as 4 may open up between the cement 2 and well casing 1.

By my invention such passages 4 may be sealed up by first perforating the pipe 1 by a perforating device 5 and then forcing cement through the perforations produced to seal such passages 4.

In Fig. 2 the perforating device is shown in one of vits preferred forms, such perforating device comprising a body 6 of steel or other metal .having a chamber 7 in its center. 8 indicates a number of lateral wa s extending from the outside of the bo y 6 to the center of the chamber 7 which receive slugs 9 of a size to closely fit the ways 8 and preferably provided with pointed ends 10 fastening the outside of the body 6. The slugs 9 extend 'a distance within the chamber 7 and there engage anvils 11 shaped to fit the chamber 7 and slide therein, said anvils 11 vbeing normally held by .the slugs 9 a distance from the side walls of' the chamber 7 and being spaced apa-rt to provide a central explosive chamber 12.

The central explosive chamber 12 is filled with an explosive material 13 such as trinitrotoluene or blasting gelatine and has embedded therein a detonating cap 14, the cap 14 being provided with electrical means 15 by which the cap can be exploded from the to of the well.v The body 6 is provided with a vertical bore 16 extending upwardly from the center of the chamber 7 by which the explosive charge may be inserted into the space between the anvils 11, and a plug 17 is threaded into the bore 16 to close the opening and also to provide a handle 18 by which the device may be raised and lowered within the well casing 1. Duets 19 are alsol provided in the body 6 lea-din from the outside to a point normally close by the anvils 11l but adapted to be uncovered when the anvils 11 are forced to the side walls of the chamber 7 When em loying this form of the invention the bo yy and parts carried thereby are lowered upon a line, such as 20, down to the position within the well hole where the perforations are to be made. The c ap 14 1s then exploded by means of an electrical lead 15 which causes an explosion of the mam charge between the anvils 11. The explosionof such char e throws the anvils 11 to the side walls of t e chamber 7, the4 anvils 11 thus shoot the slugs 9 from the body of thel perforating device which then pass through the well casi-ng 1 leaving a clean form of pel.'- foration therein. The body 6 is of course made of sufficient strength to resist the force of the explosive charge 13. The anvils 11 arriving at the sides of the chamber 7 open the ducts 19 so as to permit an' escape of the gases through such. ducts.-

In the form of the invention` shown in y Figs. 3 and 4 the perforating device comprises a body 21 having a groove 22 therearound which receives a strap 23 to which'a line may be attached for raising andv lowering the body 21 within the well hole. The body 21` is bored out as indicated at 24 from one side thereof to provide a chamber for lholding an explosive charge. and 'directing the force ofthe explosive laterally from the perforating device andagainst a well casing, the ex losive 25 `either entirelyk il 'ng the inner end of t e bore, the outer end being closed by a slug 26-havilng a pointed end 27. Near the end of the bore 24 a detonatin cap 284 is imbedded in the ex losive 25 an a vertical passage 30 to the top o the we l.

The vertical passage 30 communicates with the bore 24 and receives a plug 31 closing the passage, packing mate-rial 32 preferably being posltloned between the -plug 31 and the explosive charge 25. v.

This embodiment of the mventwn diiiera rilling the bore or connected to wires 29 leadin t rou h y well casing from the precedin method as it eliminates the anvils 11 whic are not necessary to all forms of the invention and moreoverhas a uniform bore chamber 24 and may, if desired, dispense with the use of the slug 26. The slug 26 may be eliminated, since the force of the explosive charge is so confined by the body 21 and directed to the discharge from said body, that when such slug 26 is elimlnated the force of the explosive charge is directed againstthe casing and perforates the same by burning therethrough, as will be more fully pointed out in connection with the embodiment illustrated in Fig. 6.

The form of the invention shown in Fig. 6 has an inverted T-'sha-ped body 32, the 1ower end of which is provided with a bore 33 extending from end to end of the body and the upper portion being provided with a bore 34 communicating with the bore 33 and enlarged at its upper end as indicated at 35 to recelve a plug 36. The smaller end of the bore 34 receivesa casing 37 closely fitting the bore 34 and holding a detonating cap 38 the cap 38 being connected with electrical leads 39 by which it may4 be fired. The lower bore 33 is preferably filled from end to end with an explosive charge. This form of the invention is preferable when dis nsing with 'the slug. The detonation o the cap 38 will cause the explosive in the bore 33 to perforate a well pipe by burning through the pipe as the body 32 ismade v'of' Vsuflicient strength to resist the force of the form of the invention as shown herein, and

various modications may be made without departing from the spirit of the invention, and ,the invention is ofthe scope set forth in the appended claims.

I claim:

1. The method of ing in place in a wel lowering an vex losive charge down the well casing inside o a .body of sufficient strength to resist the ex lesion of the charge and having openings or directing the force of the explosion out against the well casing, and lhen firing the charge in place in the well o e. l

2. A method. of perforating a well casing perforating a wellj casin place in awell hole, which comprises lowi ering an explosive charge' down the well casing, exploding the charge, and directing the force of the charge in the direction of the and thereby perforating the same.

.3. A device fof raming a Wuming hole, which' comprises. .115

1n place within a Well hole, .which device comprises a body, an explosive charge Within the body, said body having means for directing the force of the explosive against a Well casing, and being of suilicient strength to resist the destructive force of said charge, and means for detonating the charge when lowered down in a Well hole.

4. In a device forvperforating a Well cas-1 ing in place in a Well hole,'the combination of an explosive charge, a body holding the explosive charge, said body being sufficiently strong to resist the force Yof the explosive charge, lateral Ways for directing the force of the explosive towards the well casing, slugs normally closing the Ways, and means for detonating the explosive in place in a well hole.- v

i 5. A device for perforating a Well casing when in place in a Well hole, Which device comprises in combination a metal body adapted for holding an explosivecharge,

ways for directing the force of the explosivelaterally against the Well casing, slugs normally closing the Ways, anvils between the slugs and explosive, and means for detonat- 'lng the vexplosive in place Within the Well ole.

6. A device for perfora-ting a Well easing when in place in the Well hole, comprising a body adapted .to hold an explosive charge, said body being lowerable Within the Well casing, and having means for directing the force of the explosive against such Well casing when suspended therein, the body being of sulicient strength to resist the destructive force of said charge, and means for suspending and detonating the charge in place in a Well hole.

Signed at Los Angeles, California, this 25th day of February, 1924.

SIDNEY W. MlMS.