| 摘要 |
Two hollow hemispheres diametrically drilled to fit around a pipe casing, and exteriorly flanged for bolting together to isolate a section of said casing intermediate its ends, said hemispheres being drilled through in a plurality of places to receive drills for penetrating steel and cement. Respective nipples are exteriorly secured to the hemispheres around each drill hole. A screw cap may be used to close each nipple when not in use. In operation a valve may be attached to the nipple and a drill inserted therein for drilling through the concentric metal and cement casings of the casing pipe and the production tubing strings in the center thereof. If a hollow drill has been used it can remain in place, otherwise it is withdrawn. A plastic snake of a flexibility and size to pack around the tubing strings is forced into the drilled hole to isolate the drilled break in the tubing strings from the rest of the casing and the strings above the break. Cement and mud is pumped through connecting hoses and the installed valve into the drilled hole to stop up the well. If well pressure is great, a plurality of drills up to the number of drill holes in the hemispheres can be used to effect a plurality of penetrations into the pipe casings for pumping a larger volume per minute of stopping material into the casing and the lower part of the tubing strings. A second species of the invention comprises a cylindrical member divided diametrically into halves for bolting together around a pipe casing. Drill holes are defined through the cylinder walls, and nipples are secured therearound similar to the ones described for the hemispheres. Where six or less drill holes are required this species is the preferred one.
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