Патент USA US2407081код для вставки
2,407,081 Patented Sept. 3, 1946 UNITED STATES PATENT OFFICE 2,407,081 GUN PERFORATOR FOR WELL CASING Mordica 0. Johnston, Glendale, Calif. Application November 27, 1944, Serial No. 565,261 4 Claims. (Cl. 164-05) 1 2 ating with a special projectile acting to seal the ?ring chamber and to retard movement of the projectile until a desired ?ring power has been developed within the con?ned ?ring chamber. The invention is illustrated by way of example in the accompanying drawing in which: This invention relates to oil well tools, and par ticularly pertains to a gun perforator for well casing. In gun type perforators for well casing, as shown in my Patent No. 2,048,451, issued July 21, 1936, and entitled “Casing perforating gun,” a substantially cylindrical body member was pro Figure 1 is a view in section and elevation gen erally indicating the application of the gun per vided which was lowered into a well casing on a forator to a well bore and its casing. string of pipe, the body member being formed Fig. 2 is an enlarged view in central vertical with a plurality of ?ring chambers sealed at their 10 section showing the construction and arrange outer ends by a projectile and a barrel and within ment of the ?ring chambers and barrels incor which an explosive charge was ignited by elec porated within the perforator body. trically controlled ?ring mechanism. In other Fig. 3 is an enlarged view in elevation with types of perforating guns the barrel has been parts broken away showing the projectile and its made with interconnecting ?ring chambers with sealing means. in which the explosive charges contained in the Referring more particularly to the drawing, l0 several chambers are successively ignited as ?re indicates a string of pipe ?tted with a pin II passes through a duct from one chamber to the at its lower end to receive a box section l2. other. In all of these types of gun perforators Fastened into the lower end of the box section heretofore mentioned the construction of the ?r is a cylindrical ?ring rod l3 carrying a ?ring unit ing chambers and the projectiles therefor have I4. This unit is here shown as ?tted with yield been disposed at successive spaced intervals along able shoes l5 by which it is centered in a well the body member of the gun and with the axes casing IS. The unit may be of any desired con struction to ignite a ?ring charge within a breech section 11. The breech section is formed with a lower threaded pin portion I8 which engages a threaded counterbore 19 within the gun perfo of the barrels of contiguous ?ring units disposed at wide angles to each other so that the ?ring chambers could be properly sealed against the hydrostatic head of liquid present in the well bore. This arrangement is not altogether prac tical since the perforations formed in the well casing cannot be closely spaced. It is desirable, therefore, to design a gun perforator body carry ing ?ring chambers which may be spaced closely to each other and disposed in any desired angular arrangement radially of the perforator body, whereby a suitable pattern of perforations may be formed at each ?ring period of the gun. It is the principal object of the present invention, therefore, to provide a gun perforator body hav ing individual ?ring chambers and barrels so con structed as to receive a novel projectile adapted to seal the ?ring chamber and to insure suitable ?ring power while the radial angular positions of the barrels are disposed close together and need not be at wide angles to each other as is now usually the case. ' The present invention contemplates the provi sion of a gun perforator body substantially cy lindrical in shape and of a diameter to be lowered conveniently through a well casing to a point of rator body generally indicated at 20. This body may comprise any desired number of perforating units 2| which are threaded to each other at con tiguous ends and are longitudinally aligned. The lowermost one of these units is ?tted with a cap 22. This cap forms a protecting end for the unit and also seals the lower end of a ?ring duct 23. The ?ring duct extends longitudinally and cen trally through each of the perforating units 2|, and since the units 2| are fastened end to end the ?ring duct 23 will extend entirely from the breech section I‘! to the lowermost end of a duct 23 which is covered by the cap 22. Disposed along the length of each of the body members 2| is a series of ?ring chambers 24. These chambers extend transversely within a body member 2| and are 45 disposed radially with relation to the longitu dinal axis of the body member and the ?ring duct 23. The ?ring chambers 24, as shown in Fig. 2 of the drawing, are cylindrical in cross-section and are of a length to intersect the longitudinal operation, said body being formed with a plural— 50 axis of the body member 2| and the duct 23 so that sections of the duct 23 will establish com ity of explosive chambers at desired spaced levels munication between successive ?ring chambers. throughout the length of the gun body and being The longitudinal axis of the ?ring chambers 24 disposed at any desired degree of axial spacing may be arranged at any selected degree so that with relation to each other, the ?ring chamber any desired ?ring pattern may be produced. being equipped with a removable barrel cooper 3 2,407,081 Each of the ?ring chambers 24 has a cylindri cal side wall 25 which terminates in a dead end wall 26 at one end. At the opposite end of the ?ring chamber a reduced outlet bore 2'! is formed which is of circular section. The outer end of this bore terminates in a sealing seat 28 which is at the bottom of an enlarged threaded bore 29 designed to receive a removable barrel 30. This barrel is formed with a muzzle bore 3| through which a projectile passes and by which 10 the projectile is directed to impinge against the 4 frusto-conical wall around and beyond the por tion 38' of the projectile 35. V In operation of the present invention the gun perforator is assembled as shown in Fig. 1 with a desired number of body sections 2| forming the gun perforator body 25. The gun is then loaded by introducing a charge of explosive 31' into each of the explosive chambers 24. This charge of explosive is here shown as being in the form of a cylindrical stick of explosive material having a diameter substantially agreeing with the di ameter of the bore 21 leading from each of the face of the well casing. The outer end of the threaded bore 29 is ?nished by a counterbore 32 ‘explosive chambers 24. It will be recognized that which is of a depth‘ su?icient to shield the con the explosive elements 31 are of lesser diameter vexed end 33 of the barrel 30. The opposite end 15 than the diameter of the explosive chambers 24, of the barrel 30 is formed with a cylindrical coun thus providing a combustion and expansion space terbore 34 which agrees in diameter with the 59 around the explosive charge 37 and within bore 28 formed in the perforator gun body 2!, the chamber 24. The length of the stick of ex said bores being concentric with the longitudinal plosive 3111s greater than the length of the ex axis of the ?ring chamber 24 and the barrel 3B. 20 plosive chamber 24, andin fact extends entirely The ?ring chamber and barrel construction, through the bore 27 and rests against the end as previously described, are designed to accom face 43 of theprojectile when the gun is loaded. modate a projectile 35, a sealing and shear ring Prior to loading the gun the projectiles ‘35 are 36, and an, explosive charge 31'. The projectile is assembled with the rings 36. The sealing and formed with a main cylindrical portion 38 which 25 shear ring 35 is made of metal, and in View of the agrees substantially in diameter with the muzzle fact that its cylindrical bore 45 is less in diameter bore 3|. One end of the portion 38 is formed with than the diameter of the cylindrical portion 38 a nose 39 which may be of any desired shape, de of the projectile 35 it is necessary to force the pending upon the perforating Work to be done. projectile through the ring and to temporarily The opposite end of they projectile is formed with 30 stretch the ring until the bore 45 registers with an annular groove 43 which occurs a desired dis the recess 4d, at which time the reduced portion tance from the exact end of the projectile and is of the ring occurring between the faces 46 and formed in the cylindrical face of the portion 38. 15‘! will snap into position between the shoulders This groove has opposite'square shoulders All and M and 112 of the recess 40 and will form a tight 42 and an intermediate cylindrical face. The 35 seal therewith. The projectile and ring thus depth of the groove is determined, for a purpose assembled, as shown in Fig. 3 of the drawing, is to be hereinafter described, and is represented by then positioned within the bore 28 of the body a critical dimension. At the exact end of the member 2| so that the end face 49 of the ring will portion 38 of the projectile 35 a short cylindrical rest against the bottom face of the bore 28. The portion 38’ occurs. This is of the same diameter barrel 3!) is then screwed in place with the body as the main portion 38 and provides an end face 38 of the projectile 35 extending outwardly within 43 against which the explosive force of the ex the muzzle bore 3!. As the barrel 3!) is screwed plosive charge 3‘! is directed. tightly into place within the threaded bore 29 Made separately and subsequently mounted the outermost portion of the ring 38 will register upon the projectile 35 is the sealing ring 36. This 45 With the counterbore 34 in the end of the barrel ring is cup-shaped and is formed with an outer and pressure will be exerted to form a tight seal cylindrical face 44 which agrees substantially with between the barrel and the face 46 of the ring the diameter of the bore 28 in the perforator body and a tight seal between the end of the bore 28 2! and also agrees in diameter with the counter and the face 49 of the ring. At the same time the bore 34 formed in the barrel 30. The length of 50 end face 42 of the projectile will be drawn against the sealing ring 36 is slightly greater than the the end of the stick of explosive 37 so that the ex combined lengths of the bore 28 in the gun per plosive will be held in place ?rmly. After the gun forator body 2| and the counterbore 34 in the perforator has been completely loaded it may be barrel 30. The ring 36 is formed at one end with lowered into the well to a desired level, after a cylindrical bore 45 which agrees in diameter 55 which the mechanism within the portion [4 is with the diameter of the cylindrical portion of manipulated to produce initial ignition of explo the recess All) which is formed on the body por sive within the breech block ll. This explosive tion 38 of the projectile 35-. The length of the will then burn downwardly through the ?ring cylindrical bore 45 agrees in dimension with the ducts 23 and successively although substantially distance between the shoulders 4i and 42 of the 60 simultaneously produce ignition of all of the ex plosive charges 31 in the various explosive cham recess 40 on the projectile 35 and is de?ned by bers 24. When an explosive charge 31 is ignited the end face d6 of the ring and a shoulder 41 it will begin to burn and create gaseous pressure within the ring. The shoulder '41 has a diameter within the chamber 24. The immediate move agreeing with the diameter of the portion 38 of the projectile 35. A tapered counterbore 48 is 65 ment of the projectile 35, however, will be re strained by the shear ring until suf?cient ?ring formed within the ring 36 and extends from the power has been built up within the explosive shoulder 41 to the end face M) of the ring, which chamber 24. This ?ring power is of course deter face is parallel to the opposite end face 46. The mined by the amount of explosive 31, the size of taper of the side wall of the counterbore 48 is 70 the explosive chamber 24, the thickness of the here indicated as being approximately nine de wall represented between the faces 46 and 41 of grees, for purposes to be hereinafter explained. the sealing ring 35, and the character of the It will of course be understood that this angle metal from which the ring is made. It is to be might be changed to create di?erent conditions that while the sealing and shear ring as desired. This forms an outwardly ?aring 75 understood 36 has been described as being separate from the 2,407,081 5 projectile that in certain instances it might be circular cross-section with its longitudinal axis disposed in a plane normal to the longitudinal axis of the body, one end of said chamber being closed and the opposite end being formed with a restricted outlet opening, a counterbore at the outer end of said outlet opening providing a seal muzzle bore 3i to strike the well casing or forma tion encountered in its path. Thus, the casing ing shoulder and against which shoulder the seal will be perforated, and if the ?ring power is great ing and shear ring of the projectile rests, a enough an opening will be made in the forma threaded counterbore extending beyond the ?rst tion to facilitate in the flow of cognate ?uid from 10 named counterbore, and a threaded barrel adapt ed to be mounted within the threaded counter the formation. bore with its muzzle bore receiving the outwardly It will be understood that due to the fact that found desirable to form it integral with the pro jectile. When the explosive force is suf?cient to shear this wall thickness the projectile 35 will be released and will be forced outwardly through the the ?ring duct 23 is disposed centrally of the body projecting portion of the projectile, the inner face 2| it is possible to easily locate the ?ring cham of the barrel cooperating with the shoulder of the bers 24 and the barrels 39 in any desired angular counterbore to grip the sealing ring. . 3. In a gun perforator adapted to ?re a projec radial relation to each other, since individual ?r ing mechanism is not necessary and the explosive tile which is cylindrical in cross-section and charges do not need to be wired individually. It which carries a sealing and shear ring adjacent will also be seen that due to the design of the the inner end thereof, a gun body adapted to be sealing ring 39 and the parts between which it is 20 lowered into a well bore and having ?ring means gripped it is possible to seal the ?ring chamber associated therewith to be controlled from the against induction or eduction of fluids under pres ground surface of the well, an explosive chamber sure, Whether it be the gases developed within the formed in the gun body, said chamber being of firing chamber or the hydrostatic pressure of circular cross-section with its longitudinal axis ?uid within the well bore, and it is also to be 25 disposed in a plane normal to the longitudinal pointed out that the design of the sealing ring axis of the body, one end of said chamber being 36 may be made to absolutely establish the mag closed and the opposite end being formed with a nitude of ?ring power developed within the ex restricted outlet opening, a counterbore at the plosive chamber 24 before the projectile is re outer end of said outlet opening providing a seal 30 ing shoulder and against which shoulder the seal leased and ?red. It will thus be seen that the gun perforator con ing and shear ring of the projectile rests, a struction here disclosed makes it possible for pro threaded counterbore extending beyond the ?rst jectiles of simple and cheap construction to be named counterbore, a threaded barrel adapted made and to be ?red by an explosive which may to be mounted within the threaded counterbore be easily handled, and that furthermore the gun with its muzzle bore receiving the outwardly pro may be quickly and easily loaded and when ?red jecting portion of the projectile, and a counter will develop any desired ?ring power. bore in the inner face of the barrel to cooperate While I have shown the preferred form of my with the counterbore in the body to receive and invention as now known to me, it will be under grip the sealing and shear ring. stood that various changes may be made in com 4-0 4. A gun perforator adapted to ?re a cylindrical bination, construction and arrangement of parts projectile having an enlarged annular cup-shaped by those skilled in the art, without departing from ring on its trailing end, said gun including a ?r the spirit of my invention as claimed. ing unit, a cylindrical body member carried at the Having thus described my invention, what I lower end thereof and being formed with a cen claim and desire to secure by Letters Patent is: tral ?ring duct communicating with the ?ring 1. In a gun perforator, a body member having unit, a plurality of explosive chambers arranged an explosive chamber therein to receive a charge at spaced intervals along the length of the body of explosive, said chamber lying in a plane nor member and intersecting the ?ring duct whereby mal to the longitudinal axis of the body and in communication will be established between con tersecting said axis, the inner end of said cham 50 tiguous ?ring chambers, said ?ring chambers be ber being closed and the outer end being formed ing circular in cross-section and having their in with a restricted outlet opening, a seat formed around the outer end of the outlet opening to receive an annular ?ange portion of a projectile, ner ends closed, an opening at the opposite end of the ?ring chamber of reduced diameter, a counterbore at the outer end of said opening a threaded bore extending outwardly beyond said 55 forming a ?at shoulder lying in a plane normal seat, a threaded barrel having a central muzzle to the longitudinal axis of the chamber, an en bore and adapted to be mounted within the larged threaded opening extending outwardly and threaded opening to receive the outer end of the being disposed concentrically of the longitudinal projectile in the muzzle bore and to cooperate axis of the ?ring chamber, a barrel formed with with the seat in the body member in engaging the 60 a central muzzle bore and threaded to be seated ?ange of the projectile and thus holding the pro within said threaded bore, and a counterbore in jectile until the ?ring power of the explosive the inner end of said barrel concentric with said shears said ?ange from the projectile. muzzle bore and cooperating with the face of the 2. In a gun perforator adapted to ?re a pro counterbore within the body of the gun to grip jectile which is cylindrical in cross-section and 65 the sealing and shear ring carried by the projec which carries a sealing and shear ring adjacent tile and to thus seal the explosive chamber while the inner end thereof, a gun body adapted to be restraining movement of the projectile until an lowered into a well bore and having ?ring means explosive force has been created within the ex associated therewith to be controlled from the plosive chamber having su?icient magnitude to ground surface of the well, an explosive chamber 70 shear the ring from the projectile. formed in the gun body, said chamber being of MORDICA O. JOHNSTON.