Patent ID: 9598939
Date: 2017-03-21
CPC Classifications: E21B

Claim:
1. A perforating tool for perforating a downhole well casing, the tool comprising: a body arranged to be disposed in a well casing and at least one cutter block moveable relative to the body between an inwardly retracted condition and an outwardly deployed condition to cut a perforation in the well casing; an activation member disposed in the body, wherein the activation member is moveable relative to the body to move at least one said cutter block between the inwardly retracted condition and the outwardly deployed condition relative to the body; a plurality of pistons arranged to move the activation member relative to the body, each said piston being disposed in a respective pressure chamber; and wherein the activation member defines a bore disposed along a longitudinal axis of the body, and wherein a plurality of ports are formed in the activation member to enable fluid to flow from the bore to each said pressure chamber such that an increase in fluid pressure in the body increases fluid pressure in each said pressure chamber to move each of the plurality of pistons relative to the body and cause the activation member to move relative to the body.