DEVICE FOR PUMPING FLUID FROM A WELLBORE

摘要

A pump device for pumping fluid from a wellbore, comprising: a piston member (38) movably arranged in a pump chamber (36) between a first position and a second position, in a manner allowing the piston member to perform a series of pump strokes, whereby at each pump stroke a volume of said fluid is pumped out of the pump chamber (36) by the piston member; a fluid conduit (20) arranged to move the piston member (38) from the first position to the second position by a selected fluid pressure increase in the fluid conduit; an inlet channel (60) connecting the pump chamber to a storage chamber (52) for receiving said volume of fluid from the pump chamber (36); first valve means (62) arranged in the inlet channel for allowing fluid flow from the pump chamber (36) to the storage chamber (52) and for preventing fluid flow from the storage chamber to the pump chamber; pressurising means (57) for applying hydraulic pressure to the volume of fluid in the storage chamber (52); an outlet channel (64) for discharging the volume of fluid from the storage chamber (52) into the fluid conduit (20); second valve means (68) for allowing fluid flow from the storage chamber (52) to the pump chamber (36) and for preventing fluid flow from the pump chamber to the fluid conduit (20); a fluid inlet (46) for inflow of said volume of fluid from the wellbore into the pump chamber (36); and third valve means (50) to prevent outflow of fluid from the pump chamber (36) to the fluid inlet (46).

主权项

1. A pump device for pumping fluid from a wellbore, comprising:
a piston member movably arranged in a pump chamber between a first position and a second position, in a manner allowing the piston member to perform a series of pump strokes, whereby at each pump stroke a volume of said fluid is pumped out of the pump chamber by the piston member; a fluid conduit arranged to move the piston member from the first position to the second position by a selected fluid pressure increase in the fluid conduit; an inlet channel connecting the pump chamber to a storage chamber for receiving said volume of fluid from the pump chamber; first valve means arranged in the inlet channel for allowing fluid flow from the pump chamber to the storage chamber and for preventing fluid flow from the storage chamber to the pump chamber; pressurising means for applying hydraulic pressure to the volume of fluid in the storage chamber; an outlet channel for discharging the volume of fluid from the storage chamber into the fluid conduit; second valve means for allowing fluid flow from the storage chamber to the pump chamber and for preventing fluid flow from the pump chamber to the fluid conduit; a fluid inlet for inflow of said volume of fluid from the wellbore into the pump chamber; and third valve means to prevent outflow of fluid from the pump chamber to the fluid inlet.