TWO-STAGE UNDERWATER ACTUATING MECHANISMS Russian patent published in 2013 - IPC E21B33/35 F15B3/00 

FIELD: oil and gas industry.

SUBSTANCE: improved two-stage actuating mechanism includes the first cylinder, piston of pressure hydromultiplier installed in the first cylinder for sliding with seal along itself and having the surface of large surface area, which is open to action of ambient pressure, and surface of small surface area. The second cylinder has end wall, piston of actuating mechanism, which is installed in the second cylinder, stock connected to piston of actuating mechanism for movement with it and having an intermediate section passing with seal through end wall of the second cylinder. At that, mechanism has intermediate chamber connecting the surface of small surface area of piston of pressure hydromultiplier to surface of large surface area of actuating mechanism, and noncondensable fluid medium in the chamber.

EFFECT: providing the movement of actuating mechanism piston to end wall of the second cylinder due to creation of pressure in intermediate chamber with sea water pressure at the depth of the device immersion, without using a power supply aboard surface vessel.

16 cl, 3 dwg