SEM. 24V, 1946. O. J. MGCLVJLLOUGH 2,407,991 PIPE RELEASING DEVICE Fil-ed July 26, 1945 *4%mE E; wm wm ß .INVENTORT @JIM gGULLOUG‘H ' /9 rfb/mfr _ Patented Sept. 24, 1946 l 2,407,991 UNITED STATE s PATENT oFFlcEl 2,407,991` PIPE RELEASING DEVICE Otis J. McCullough, Houston, Tex., assignor to McCullough Tool Company, Houston, Tex. Application July 26, 1943, Serial No. 496,140 1 claim. (Cl. 16S-1) l The invention relates to a pipe releasing device which is particularly adapted for use in a string of pipe which is stuck or lodged in a well bore at an inaccessible location and is useful in jarring loose a threaded connection so as to permit un screwing of the pipe. In the drilling of wells by the rotary method a string of drill pipe is made up of sections threaded together with couplings and this string of pipe 2 a string of pipe in a well bore and ready to be actuated to release,- the pipe. v « Figs. 2 and 3 are vertical sectional views which form a continuation one with the other and illus trate the internal construction of the tool. Fig. 4 is a transverse verticalv section taken through the explosive chamber and the locating springs of Fig. 3. ' Fig. 5 is a broken detail sectional view illustrat serves to advance the bit by rotating the bit on 10 ing a plug construction which will'determine the the bottom of the well bore. In some instances pressure at which the jar is releasedäagainst the the Ibit may become lodged in a lissure or crevice pipe. or may be otherwise stopped from rotating and In Fig. l. a string of pipe 2 has been ~illustrated the operator on the surface may continue to which may be made up of the pipe sections 3 and rotate the pipe and twist off the pipe somewhere 15 4 which are threaded together by a coupling‘ä. in the well bore. In other instances the pipe As seen in Fig. l the ends of the pipe 3 and 4 do may become stopped due to caving or coagulation not usually come in close contact with each other, of the drilling mud. Under these circumstances but may provide an open space 6 inside of the it is desirable to unscrew one or more sections of coupling 5. In this manner the lower end_‘I of the drill pipe and remove the same from the well 20 the pipe 4 forms a shoulder in the threaded con-so as to eventually salvage the pipe. While drill nection. pipe has been mentioned, other types of pipe such A pipe releasing device constitutes a tool IIJ as tubing or casing are also utilized in the well which is suspended by means of a cable I I in the bore. pipe in the well bore. This cable II serves to The present invention concerns itself with the 25 manipulate the tool by lowering and raising it in setting of the tool at the desired threaded cou the well bore. pling which is to be released, the application of The tool I0 has a plurality of springs I2 cir a torque tending to unscrew the pipe and then cumferentially arranged thereon as seen in Fig. 4 the creation of a high pressure blast at the which normally extend outwardly 4beyond the pe threaded coupling which will tend to jar the 30 riphery of the tool and are arranged tov engage coupling and in this manner to loosen the threads. a shoulder such as 'I in a, pipe connection. It It is therefore one of the objects of the inven seems obvious that the tool can be lowered tion to provide a pipe releasing tool which can through the pipe by means of the cable II until be located so as to apply a jar at a threaded con the desired elevation is accomplished. This ele nection in a well bore. 35 vation is determined »by the amount of pipe which Another object of the invention is to provide a the operator believes may be unscrewed when the device for latching the pipe releasing tool at the pipe releasing tool of the present invention is elevation of the threaded coupling to be released. utilized. The tool is then raised by pulling up on Still another object of the invention is to pro ` the cable II until the springs I2 snap into a vide a, pipe releasing tool wherein a primer serves threaded coupling. This prevents further upward to set oiï a charge of explosive to provide a source movement of the tool and the operator is advised of high pressure to jar the pipe. that his tool is anchored in a threaded coupling. Another object of the invention is to provide This arrangement of structure is seen in Fig. 1. an electrically ñred pipe releasing device wherein The springs I2 may be connected to the tool by the electric contacts are sealed by confining a 46 the screws I3. resilient material and applying a, pressure thereto. The tool I0 is made up of a cap I4 which is Another object of the invention is to control threaded at I5 into the Ibonnet I6. This bonnet the pressure at which a pipe releasing device will I 6 is in turn connected to the nipple I1 which discharge a, pressure therefrom against the pipe is threaded at I8 to the housing I9. A foot piece to be released. 60 or tail pipe 20 may be carried by the lower end Other and further objects of the invention will of the housing if desired. be readily apparent when the following descrip As seen in Fig. 2 the cable II extends through tion is considered in connection with the accom the passage 22 in the cap I4 and into the bon panying drawing wherein: net I6. This cable may preferably carry an elec Fig. 1 is a side elevation of the tool located in 55 tric contact 23 which is anchored in a sealing ' 2,407,991 4 3 46 prevents escape of any substantial amount of member 24 disposed in the recess 25 in the lower the pressure from the explosion chamber. end of such bonnet. Th‘e electrical connection Fig. 4 shows three of these openings or dis 26 extends through the cable to the contact 23. charge outlets 45 so that a uniform jar is applied This Wire 26 is insulated from the bonnet i6 by the provision of the insulating material 24. The Ul to the circular threads. Fig. 5 shows a modiiied type of plug 46 in the main portion of the cable is enclosed in a packing form of a cylindrical ñgure 41 which may be a 21 which is held in place by the cap I4. phenolic member which is driven into the posi A tool of this sort being lowered into a well tion seen in Figure 5 and can only be dislodged bore is subjected to tremendous hydrostatic pres sure and. in` order to prevent'leakag'el into the 10 by theV application of a tremendous force. In operation the tool willbe lowered through tool which' might short »circuit the y#wire 26 itis’ Hthe pipe ¿l to approximately the position of the desirable to set up and maintain inside the tool coupling which is to be unscrewed. The tool is a pressure in excess of the pressure expected to then moved upwardly until the spring ñngers be encountered in the well bore. To accomplish catch in the threaded coupling as seen in Fig. this the plugs 35 of material have been inserted 1. A torque is then preferably applied to the through the openings 3l in the side of the bon pipe él in any suitable manner tending to unscrew net and the set bushings 32 may be screwed into the threads of the coupling. While this torque the openings in order to compress the plugs 3€) is applied the tool will be ñred so as to apply a and the packing material 24. In this manner th'e desired pressure may be set up around the 20 sharp jarring action to the coupling which will tend to loosen the threaded connection so that wire 26 to prevent any leakage into the tool. the torque will unscrew the coupling. Fig. 3 shows the nipple l1 as having the lower Broadly the invention- contemplates a tool for end of the bonnet E6 threaded thereinto so that applying a jarring action to a pipe in a well bore the contact 23 projects into the primer chamber 34 in the nipple Il. This primer chamber is ar 25 wh'erein the tool can be accurately located at the positionl where the jarring action is to be ap ranged to receive an adapter 35 and the primer 36 which is held in position by a spring 3l. What is claimed is: This primer may be of any suitable type which Apparatus for use in well tubing within a is arranged to be ’ñred when a vflow of current occurs through the-fconta'ct‘äí-l so as to ignite 30 well bore to facilitate unthreading of sections of Well tubing at a joint formed by »an internally the primer. The ñri-ng of this primer discharges threaded female coupling member surrounding ñre into the chamber 39 from whence it flows and threadedly connected to'externally threaded through the passage 46 into the explosion cham ends of tubing sections with the tubing section ber 4l. This passage ¿l0 is of relatively> small ends spaced from each other, comprising a hous diameter so as to conduct the fire from the ing arranged to be lowered into the well tubing primer into th‘e explosion chamber. and having an explosion chamber therein, a The explosion chamber Il! is disposed in the charge of explosive in said chamber, a plurality housing i9 and is arranged to contain a charge of pressure outlet ports in said housing extending 43 of gun powder or other suitable explosive which will be detonated by the ñre from the pas 40 from said chamber radially outward in a single substantially horizontal plane to discharge the sage 49. It seems obvious that the size of this products of detonation of the explosive in a plu charge can he varied in accordance with cir rality of substantially horizontally and radially cumstances encountered. A lateral outlet 45 directed jets, means on said housing arranged from the explosion chamber is shown as being to contact the end of one of th'e tubing sections closed by the plug or disk 46 which is firmly fitted for positioning the housing with said outlet ports therein. When the detonation occurs this plug and the jets of explosive products directed at will be blown from the opening 45 against the circumferentially'spaced portions of the interior inside of the lcoupling 5 as will be apparent from surface of said female coupling member between Fig. 1. This plug 46 may ñt snugly in the open the spaced ends of the tubing sections, and ing so that a predetermined pressure will have means for detonating saidv explosive. to build up in the explosion chamber before the OTIS J. MCCULLOUGH. plug is dislodged. The small area'of the passage plied. ' . '