Patent ID: 8833465
Filing Date: 2014-09-16
Classification: E21B,F15B

Abstract:
1. An accumulator for a subsea blowout preventer unit including a blowout preventer, including: a body including a hydraulic fluid chamber and a precharge gas chamber, wherein the hydraulic fluid chamber has a smaller inner diameter than the precharge gas chamber; a hydraulic fluid port in fluid communication between the hydraulic fluid chamber and the subsea blowout preventer; a hydraulic piston slidably and sealingly mounted in the hydraulic fluid chamber; a charge piston slidably and sealingly mounted in the precharge gas chamber and unconnected with the hydraulic piston; a pressure port for receiving pressure to provide a force on the opposite side of the charge piston from the hydraulic piston; and wherein the precharge as chamber is pressurizable by a precharge gas disposed between the hydraulic piston and the charge piston.