Actuation cylinder for inside blow-out preventer valve

An inside blow-out preventer (IBOP) actuation cylinder comprising:

• a first hydraulic fluid port;
• a second hydraulic fluid port;
• a movable cylinder movable by a difference in hydraulic fluid pressure between the first and second hydraulic fluid ports, wherein movement of the movable cylinder causes an IBOP valve to open or close;
• a pilot port fluidly couplable to at least one pressure sensor configurable to detect pressure of fluid from the pilot port to determine a current state of the movable cylinder;
• a first cavity fluidly coupled to a high pressure one of the first and second hydraulic fluid ports;
• a second cavity fluidly coupled to a low pressure one of the first and second hydraulic fluid ports;
• wherein the pilot port is fluidly coupled to the first cavity when the movable cylinder is retracted and the pilot port is fluidly coupled to the second cavity when the movable cylinder is extended;
• a first fluid passage extending through the movable cylinder, the first fluid passage fluidly coupling the first cavity with the high pressure one of the first and second hydraulic fluid ports;
• and
• a second fluid passage extending through the movable cylinder, the second fluid passage fluidly coupling the second cavity with the low pressure one of the first and second hydraulic fluid ports.