Perforation allows production of oil from specific depths predetermined from logging data.
They are designed to make clean holes in the casing and to penetrate several inches outward into the surrounding oil-bearing strata. Consider two perforator charges aimed horizontally in opposite directions inside a steel carrier tube that has been inserted down-hole in a main oil well casing. The perforators are very similar to a current industrial design, with a conical copper liner surrounded by a high explosive material and a steel case. The carrier tube is positioned flush against one side of the well casing. Energy released in the detonated explosive then causes the liners to converge and form shaped-charge jets that perforate the steel carrier tube and casing, and penetrate into the surrounding rock.