US2725940A

US2725940A - Dump bailer for wells

Info

Publication number: US2725940A
Application number: US452098A
Authority: US
Inventors: Garold A Shidell; Clyde L Bonds
Original assignee: Mccullough Tool Co
Current assignee: Mccullough Tool Co
Priority date: 1954-08-25
Filing date: 1954-08-25
Publication date: 1955-12-06
Anticipated expiration: 1972-12-06

Description

Dec. 6, 1955 G. A. sHlDELl. Erm.

DUMP BAILER FOR WELLS Filed Aug. :25, 1954 IN V EN TORJ` 6. A. Jb/o/e# C. L. [fonc/J I H /f IINIII i JJ, .in! "a*t.............`

vf 5 M Mw a Y ATTO/F/VEY United States Patent l@ef-:Giilice 2,725,940 Patented Dec. 6, 1955 DUMP BAILER FOR WELLS Application August 25, 1954, Serial No. 452,098 s claims. (cl. 16a-63) This invention relates toa well tool of the type commonly referred to as a dump bailer which is employed for depositing in a well various liquid, solid and semisolid materials, such as cement, sand and lgravel, chemcals and plastic materials for purposes of sealing', plugging, and treating the well generally. Conventional dump bailers employ mechanically operated valves which require a bridge or seat, or other solid obstruction in the well bore to cause the bailer valve or closure to open and discharge its contents. Y

The present invention has for its principal object the provision of a form of dump bailer which eliminates the need for such actuating obstructions and which may be opened at any point along a well for discharge of its contents.

A further object is to provide an improved bailer construction in which the discharge opening is closed by a frangible closure member which is adapted to be shattered by an explosive charge set off inside the tool.

A more specific object is to provide a dump bailer having one or more discharge openings closed by a glass cylinder which is shatterable by an explosive charge positioned therein in order to open the bailer for discharging its contents.

Other and more specific objects of this invention will become apparent from the following detailed description when read in conjunction with the accompanying drawing which illustrates a useful embodiment of the invention.

In the drawing:

Fig. l is an elevational view of the bailer shown in position in a well casing;

Figs. 2 and 3, together, constitute a longitudinal, generally sectional, view of the bailer, Fig. 2 illustrating the upper portion and Fig. 3 the lower portion thereof.

Referring to the drawing, the bailer, which is designated generally by the numeral 5, is secured to a generally conventional rope socket, designated generally by the numeral 6, mounted on the end of a cable 7 employed to lower the device into a well casing 8 lining the bore of a well 9.

The bailer comprises a plurality of tubular sections 10--10 connected together end-to-end by any suitable means, such as internal collars 11, to form a hollow container. It will be understood that as many sections of pipe and connecting collars may be employed as may be found desirable to provide a container of the desired length. Threadedly secured to the lower end of the lowermost pipe section 10, by means of one of the collars 11, is a tubular sleeve 12, having an axial bore 13 and provided with a plurality of elongated, circumferentially spaced slot-s 14-14 cut through the wall of the sleeve to form the discharge openings for the bailer. Bore 13 is counter-bored from its lower end to form the counter-bore 15 and to provide an internal downwardly facing shoulder 16 at a point above the upper ends of slots 14. Shoulder 16 serves as an annular seat to receive the upper end of a tubular liner 17 which is constructed of readily frangible material, preferably glass. All annular L-shaped gasket 18, constructed of any suitable resilient material, is positioned between the inner end of liner 17 and shoulder 16 and extends between the portion of sleeve 12 which surrounds the upper end of liner 17. The lower end of counter-bore 15 is internally threaded at 19 to receive a closure plug 20 which is screwed into the lower end of the counter-bore and also serves as an `abutment to hold liner 17 in place within the counterbore. When plug 20 is screwed into the end of the counter-bore, it will thrust the liner tightly against shoulder 16. y An L-shaped resilient gasket 21, generally like gasket 18, is seated between the lower end of liner 17 and the upper end of plug 20 and extend-s concentrically between the exterior of the lower end of liner 17 and the adjacent portion of sleeve 12. The

gaskets

18 and 21 serve both as resilient seals and shock-absorbent protective cushions between the ends of liner 17 and the adjacent portions of the plug and sleeve. This is particularly useful when liner 17 is constructed of glass, which is a preferred embodiment, and thereby prevents glass-to-rnetal contact, while providing eltective fluidtight seals between the liner and the sleeve. A set screw 22 or other locking device is employed to lock plug 20 to sleeve 12 when the plug has been screwed into the sleeve to exert the desired degree of compression on liner 17.

The uppermost section 10 of the bailer body is provided through the side thereof near its upper end with an opening 23 through which material to be delivered into the well by the bailer may be introduced into the bailer. A top closure plug 24 is inserted in the upper end of the uppermost section 10 to close the upper end of the bailer and is adapted to be connected to rope socket 6. Plug 24, when inserted in the end of section 10, may be secured therein in any suitable manner, as by means of screws 25 and by welding, indicated at 26.

Plug 24 is provided with an axial bore 27 in which is removably inserted an electrode contact assembly 28 of generally conventional form which forms an electrical connection between an electrical conductor 29, which is embodied in, and forms a part of, cable 7, and electrical leads 30 which extend through the interior of the bailer. Secured to the lower end of leads 30 is an electricallytired body of explosive, such as a well known explosive cap or fuse 31, which is positioned in the bore of liner 17. It will be understood that cable 7, with conductor 29 therein, leads to the ground surface where any suitable source of electric current, not shown, may be impressed on the conductor 29 in order to transmit current to cap 31 to explode it.

The above-described device is operated in the following manner: The bailer is assembled, as shown, with the explosive element in place in the bore of liner 17. The material to be transported into the well and discharged therein from the bailer is introduced through window 23 into the interior of the bailer and the thus loaded device will be lowered into the well to the point at which the material is to be deposited or discharged. When that point has been attained, current is applied through conductor 29, electrode assembly 2S and leads 30 to the explosive element 31 which will thus be set 0E and will shatter liner 17, allowing the contents of the bailer to discharge through openings k14 into the well bore.

The device may be re-used by removing plug 20 and installing a new liner 17. The electrode assembly and its connected wires may be withdrawn from the interior of plug 24 and a new explosive element 31 connected thereto vand re-inserted into the device to prepare it for re-use.

The quantity of explosive required to shatter liner 17 will be variable depending generally upon the character of the material from which the liner is constructed. As noted, glass is the preferred material for the liner, but the liner may be constructed from rigid, but frangible, plastic material, or from frangible metallic material.

It will be understood that various changes and modifications may be made in the details in the illustrative embodiment, within the scope of the appended claims, but without departing from the spirit of the invention. What we claim and desire to secure by Letters Patent 1. A dump bailer for wells, comprising, a tubular body, a closure for its upper end including means for attaching the body to a lowering cable, a iller opening in the wall of the body adjacent said closure, a tubular sleeve coaxially connected to the lower end of the body, a removable plug closing the lower end of the sleeve, a downwardly facing annular shoulder in the bore of the sleeve axially spaced from the plug, said sleeve having a discharge passage through the wall thereof between said shoulder and said plug, a tubular frangible liner coaxially positioned in the bore of said sleeve opposite said passage and having one end abutting said shoulder and the other end abutting said plug, annular resilient seal means disposed to form uid-tight seals between the liner and the wall of said sleeve at points above and below said passage whereby to close off said passage, an electrically red explosive charge positioned in the bore of the liner, and means carried by the cable for tiring said charge whereby to shatter said liner and open said passage.

2. A dump bailer as dened by clairn 1, wherein said liner is constructed of glass.

3. A dump bailer as dened by claim 1, wherein said seal means include portions positioned in axially compressible relation between the opposite ends of said liner and said shoulder and plug respectively.

4. A dump bailer as dened by claim 1, wherein said closure plug is threadedly inserted in the lower end of the sleeve whereby to adjustably urge said liner toward said shoulder.

5. A dump bailer for wells, comprising, a tubular body, a closure for the upper end of said body including means for attaching the body to a lowering cable having electric current carrying leads incorporated therein, a filler opening in the wall of the body adjacent the closure, a tubular sleeve coaxially connected to the lower end of the body, a threaded closure plug adjustably extendible into the lower end of said sleeve, a downwardly facing annular shoulder in the bore of said sleeve vertically spaced from the inner end of the plug, a plurality of angularly spaced openings through the wall of said sleeve between said shoulder and said plug, a tubular glass liner coaxially mounted in the bore of said sleeve having one end urged toward said shoulder by inward movement of said plug, annular resilient sealing gaskets between the ends of Said liner and the respective abutting surfaces of said shoulder and said plug, an electrically fired explosive charge positioned in the bore of said liner, and electrical conductors connecting said charge to said current carrying leads.

References Cited in the le of this patent UNTT ED STATES PATENTS Re.21,356 Pitzer Feb. 13, 194() 1,592,104 Hallvarson July 13, 1926 2,640,548 Baker lune 2, 1953