Patent ID: 11946330
Assignee: ARDYNE HOLDINGS LIMITED
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 9:
10. A method of operating a hydraulic actuator on a pipe string in a low level well, comprising the steps:
(a) attaching a downhole assembly on the pipe string, the downhole assembly comprising a hydrostatic equalisation device,
a hydraulic actuator and
a valve;

(b) opening the valve:
(c) running the pipe string and the downhole assembly into the well and flowing fluid through a central bore of the hydraulic actuator and a throughbore of the pipe string;
(d) closing the valve, blocking fluid flow through the central bore and diverting flow from the throughbore into a chamber in the hydraulic actuator via an access port;
(e) increasing fluid pressure in the throughbore at the access port to cause fluid to entering the chamber to act on a first side of a piston in the chamber, moving the piston relative to the chamber, from a first position, and thereby actuating the hydraulic actuator;
(f) releasing fluid from the chamber through an exhaust port on a second side of the piston;
(g) moving a first tubular member relative to a second tubular member of the hydrostatic equalisation device, opening a radial port on the hydrostatic equalisation device, and giving fluid access between the throughbore of the pipe string and an annulus around the downhole assembly;
(h) allowing fluid flow from the throughbore of the pipe string to the annulus outside the downhole assembly via the radial port until equilibrium is reached between the throughbore and the annulus; and
(i) flowing fluid from the annulus to the chamber on the second side of the piston via the exhaust port, moving the piston relative to the chamber, back to the first position, and thereby re-setting the hydraulic actuator.