APPARATUS FOR OVERCOMING LOST CIRCULATION IN OIL WELLS

摘要

Oil well side walls are rendered substantially impervious to fluid at a level at which lost circulation is occuring by lowering to this level a capsule containing ingredients for generating a polyurethane foam. These ingredients are mixed while the capsule is at a desired level in the oil well bore hole, the resulting generation of foam completely fracturing the capsule and effectively plugging the side walls of the oil well.