Automatic Dump Valve
AssigneeInflatable Packers International Pty Ltd
InventorsClement ROWE, David KNELL
Life of this patent
Estimating the term…
Abstract
A hydraulic dump valve (10) for use with an inflatable packer (38) in a downhole (32) installation. The hydraulic dump valve (10) includes disc springs (102, 118) to adjust the pressure of operation of the valve (10) to allow use of liquid operated packers (38) in boreholes (32) with low static water levels by isolating the hydrostatic pressure in an inflation line (51) from the packers (38) and at the same time provide communication from the inflatable packer (38) to the well annulus (30) to allow downhole deflation of the packer (38).
Claims6
A hydraulic dump valve for use with an inflatable packer in a downhole installation, the hydraulic dump valve including:
- an inlet disposed for receiving inflation fluid;
- an outlet for communication of said inflation fluid to the inflatable packer for inflation thereof;
- a piston assembly disposed for controlling flow of said inflation fluid between the inlet and the outlet;
- a spring means bearing against the piston assembly, the spring means allowing movement of the piston assembly by the force of said inflation fluid above a preset pressure differential for permitting flow of inflation fluid past the piston assembly;
- a venting port disposed downstream of the piston assembly, the venting port being closed off by the piston assembly for pressure differentials exceeding said preset pressure and being opened by the piston assembly for lower pressures;
- and
- whereby, the inflatable packer is filled with inflation fluid for pressures exceeding the preset pressure and whereby the inflatable packer deflates via the venting port for pressures below said preset pressure.
An inflatable packer assembly for use in a downhole installation, the inflatable packer assembly including:
- a mandrel with a coupling end having an inflation port;
- an inflatable packer bladder mounted upon the mandrel and inflatable via the port;
- a hydraulic dump valve mounted in the coupling end, the hydraulic dump valve including:
- an inlet disposed for receiving inflation fluid;
- an outlet for communication of said inflation fluid to the inflatable packer for inflation thereof;
- a piston assembly disposed for controlling flow of said inflation fluid between the inlet and the outlet;
- a spring means bearing against the piston assembly, the spring means allowing movement of the piston assembly by the force of said inflation fluid above a preset pressure differential for permitting flow of inflation fluid past the piston assembly;
- a venting port disposed downstream of the piston assembly, the venting port being closed off by the piston assembly for pressure differentials exceeding said preset pressure and being opened by the piston assembly for lower pressures;
- and
- whereby, the inflatable packer bladder is filled with inflation fluid for pressures exceeding the preset pressure and whereby the inflatable packer bladder deflates via the venting port for pressures below said preset pressure.
A method of operating an inflatable packer in a well, the method including the steps of:
- injecting inflation fluid into the inflatable packer via a hydraulic dump valve including:
- an inlet disposed for receiving inflation fluid;
- an outlet for communication of said inflation fluid to the inflatable packer for inflation thereof;
- a piston assembly disposed for controlling flow of said inflation fluid between the inlet and the outlet;
- a spring means bearing against the piston assembly, the spring means allowing movement of the piston assembly by the force of said inflation fluid above a preset pressure differential for permitting flow of inflation fluid past the piston assembly;
- a venting port disposed downstream of the piston assembly, the venting port being closed off by the piston assembly for pressure differentials exceeding said preset pressure and being opened by the piston assembly for lower pressures;
- blocking inflation fluid from entering the inflatable packer with the piston assembly for inflation fluid pressures below the preset pressure;
- permitting inflow of inflation fluid into the inflatable packer via the piston assembly for inflation fluid pressures exceeding the preset pressure;
- and,
- permitting flow of said inflation fluid out of the inflatable packer via the venting port when pressure of the inflation fluid upstream of the hydraulic dump valve falls below the preset pressure.
Dependencies are inferred from the claim text.