Patent ID: 9611727
Date: 2017-04-04
CPC Classifications: E21B

Claim:
1. A method for fracturing a well in a formation, the method comprising the steps of: a) providing an apparatus having at least two valves, each valve having a key profile disposed thereon, wherein the key profile of each of the at least two valves is different from the key profile of the other of the at least two valves and a piston that is slidable between an open position and a closed position; b) placing the apparatus in a casing string disposed in the well, the apparatus located near a production zone in the formation; c) placing a dart into the casing string, the dart having a dart profile disposed thereon, wherein the dart profile matches the key profile on only one of the at least two valves; and d) injecting pressurized fracturing fluid into the casing string wherein the fracturing fluid moves the dart through the casing string into the apparatus until it reaches one of the at least two valves with the key profile which matches the dart profile and thereby engages the key profile disposed on an interior sidewall of a tubular piston disposed within the apparatus, to place a downward force on the piston to move the piston from the closed position to an the open position wherein the fracturing fluid can pass through at least one port of the apparatus to fracture the formation.