Single trip wellbore cleaning and sealing system and method
AssigneeHalliburton Energy Services, Inc.
InventorsPhilippe Quero, Harley Jones, II
Life of this patent
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Abstract
A downhole tool for cleaning and sealing a wellbore includes a wash tool configured at a downhole end of the downhole tool to generate pulses of a first fluid at a first frequency and a first pressure for washing a target interval of a wellbore. The downhole tool further includes a plugging tool configured uphole or downhole from the wash tool to generate pulses of a second fluid at a second frequency and a second pressure for depositing a sealing plug at the target interval of the wellbore. The second fluid has a higher viscosity than the first fluid, the second frequency is lower than the first frequency, and the second pressure is higher than the first pressure.
Claims18
A downhole tool, comprising:
- a wash tool configured to generate pulses of a first fluid at a first frequency and a first pressure for washing a target interval of a wellbore;
- and
- a plugging tool in fluid communication with the wash tool and configured for depositing a second fluid at the target interval of the wellbore to form a sealing plug, the plugging tool including an electric motor and an obturation mechanism driven by the electric motor to generate pulses of the second fluid at a second frequency and a second pressure by alternately interrupting and releasing the flow of the second fluid through a fluid passage, and wherein the obturation mechanism comprises a plunger reciprocable by the electric motor to alternately block and unblock the fluid passage.
A method for sealing a wellbore, comprising:
- generating a flow of a sealing fluid;
- using an electric motor to drive an obturation mechanism to alternately interrupt and release the flow of the sealing fluid through a fluid passage thereby generating pulses at a frequency and a pressure;
- depositing the sealing fluid at a target interval, wherein the sealing fluid is solidifiable into a sealing plug at the target interval;
- and
- before depositing the sealing fluid, washing the target interval of a wellbore with pulses of a wash fluid at a higher frequency and pressure than the pluses in the sealing fluid.
A plugging tool for depositing a sealing plug at a target interval of a wellbore, comprising:
- a fluid pulse generator for generating pulses of a high viscosity sealing fluid, wherein the fluid pulse generator comprises:
- a housing;
- an electric motor,
- an obturation mechanism in the housing driven by the electric motor to generate pulses of the sealing fluid having a frequency and a pressure by alternately interrupting and releasing the flow of the sealing fluid through a fluid passage;
- and
- a reducer mechanism coupled between the electric motor and the obturation mechanism to reduce a frequency of the obturation mechanism with respect to a frequency of the electric motor.
Dependencies are inferred from the claim text.