Balanced piston pump for subsea use
AssigneeY&R Allum Pty Ltd
InventorsRonald Allum, Alan Lavery, Matthew Johnston, Rhys Horner
Life of this patent
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Abstract
A balanced piston pump (300) for use in subsea vehicles, for example in a variably buoyancy engine, includes an inlet (321), an outlet (325) and at least one fluid path between the inlet and the outlet. A piston arrangement in the fluid path includes a stepped piston (330) having a large end (333) and a small end (331). The step (336) of the piston cooperates with the body (310) of the pump to form a piston chamber (320). The ends (332, 334) of the piston are each exposed to ambient pressure. The force required to drive the pump is dependent on the difference in cross sectional areas of the ends of the pistons.
Claims25
A pump including:
- a. a pump body;
- b. at least one inlet;
- c. at least one outlet;
- d. a fluid path between the at least one inlet and the at least one outlet;
- e. at least one piston arrangement disposed in the fluid path and configured to pump fluid from the at least one inlet through the fluid path to the at least one outlet, the at least one piston arrangement including:
- i. a piston chamber;
- ii. an inlet valve;
- iii. an outlet valve;
- iv. a piston disposed to move within the piston chamber, the piston including a first outer end surface at a first end of the piston and a second outer end surface at a second end of the piston;
- v. a piston drive for driving the piston within the piston chamber, the piston drive operatively attached to the first end of the piston;
- f. wherein at least one of the first outer end surface and the second outer end surface of the piston are exposed to an ambient pressure;
- and
- g. wherein a surface area of the first outer end surface is smaller than a surface area of the second outer end surface such that an ambient pressure force on the second end is greater than an ambient pressure force on the first end.
A pumping system for use in a subsea vessel, the pumping system including:
- a. a pressure vessel;
- b. a main pump disposed to pump fluid from within the pressure vessel, the main pump including:
- i. a pump body;
- ii. at least one inlet;
- iii. at least one outlet;
- iv. a fluid path between the at least one inlet and the at least one outlet;
- v. at least one piston arrangement disposed in the fluid path and configured to pump fluid from the at least one inlet through the fluid path to the at least one outlet, the at least one piston arrangement including:
- a piston chamber;
- an inlet valve;
- and
- an outlet valve;
- a piston disposed to move within the piston chamber, the piston including a first outer end surface at a first end of the piston and a second outer end surface at a second end of the piston;
- a piston drive for driving the piston within the piston chamber, the piston drive operatively attached to the first end of the piston;
- vi. wherein at least one of the first outer end surface and the second outer end surface of the piston are exposed to an ambient pressure;
- and
- vii. wherein a surface area of the first outer end surface is smaller than a surface area of the second outer end surface such that an ambient pressure force on the second end is greater than an ambient pressure force on the first end.
A subsea vehicle including a variable buoyancy engine, the variable buoyancy engine including:
- a. a pressure vessel;
- b. a main pump disposed to pump fluid from within the pressure vessel, the main pump including:
- i. a pump body;
- ii. at least one inlet;
- iii. at least one outlet;
- iv. a fluid path between the at least one inlet and the at least one outlet;
- v. at least one piston arrangement disposed in the fluid path and configured to pump fluid from the at least one inlet through the fluid path to the at least one outlet, the at least one piston arrangement including:
- a piston chamber;
- an inlet valve;
- and
- an outlet valve;
- a piston disposed to move within the piston chamber, the piston including a first outer end surface at a first end of the piston and a second outer end surface at a second end of the piston;
- a piston drive for driving the piston within the piston chamber, the piston drive operatively attached to the first end of the piston;
- vi. wherein at least one of the first outer end surface and the second outer end surface of the piston are exposed to an ambient pressure;
- and
- vii. wherein a surface area of the first outer end surface is smaller than a surface area of the second outer end surface such that an ambient pressure force on the second end is greater than an ambient pressure force on the first end.
Dependencies are inferred from the claim text.