Motor saver sub for down hole drilling assemblies
AssigneeWWT International, Inc.
InventorsRudolph Ernst Krueger, V, Eric O'Neal
Life of this patent
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Abstract
A down hole drilling tool for preventing overpressure strain on surface pumping equipment or a down hole drilling motor having a housing and a circulation port and four hydraulic valves positioned on the housing actively working together to affectively open the circulation port to drilling annulus at a high pressure setting and dose the circulation port to annulus at a low pressure setting, the four hydraulic valves include a high pressure setting valve, a low pressure setting valve, a control valve and a fixed setting valve.
Claims20
A down hole drilling tool for preventing overpressure of surface pumping equipment comprising:
- a housing having a circulation port;
- and
- four hydraulic valves positioned on the housing actively working together to effectively open the circulation port to annulus at an overpressure condition of the down hole drilling motor and to reset the down hole drilling tool to close the circulation port to annulus at a free spin condition of the down hole drilling motor.
The tool of 6 wherein the tool operates to open and close the circulation port without adjusting a drilling pump rate.
A down hole drilling assembly comprising:
- a drill bit;
- a drive motor for rotating the drill bit;
- a tubing for supplying drilling fluid to the drive motor;
- a drilling fluid pump for delivering drilling fluid through the tubing to the drive motor;
- and
- a motor saver sub positioned adjacent the drive motor for preventing overpressure strain on the drive motor, wherein the motor saver sub comprises a housing having a circulation port and four hydraulic valves positioned on the housing actively working together to open the circulation port to annulus at an overpressure condition of the drive motor and to reset the motor saver sub to close the circulation port to annulus at a free spin operating condition of the drill bit.
The assembly of claim herein in the free spin operating condition of the drill bit the low pressure setting valve is closed, the high pressure setting valve is open, the control valve is open and the fixed setting valve is closed.
Dependencies are inferred from the claim text.