| CPC E21B 43/12 (2013.01) [E21B 33/038 (2013.01); E21B 34/06 (2013.01)] | 18 Claims |
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1. A method for gravity feeding coiled tubing (CT) into a wellbore having a wellhead, wherein a line is in fluid communication with the wellhead, wherein a CT stripper and pressure control equipment (PCE) are disposed above the wellhead, and wherein a safety valve is disposed in the wellbore below the wellhead, the method comprising:
injecting a fluid through the line and into the wellbore to displace reservoir fluid positioned above the safety valve such that at least a portion of the reservoir fluid is forced below the safety valve;
closing the safety valve, wherein a pressure at the wellhead is at a level to prevent gravity feeding of the CT while the safety valve is closed;
releasing pressure from a space between the PCE and the safety valve via the line until the pressure at the wellhead is reduced to allow gravity feeding of the CT;
gravity feeding the CT into the wellbore;
closing the CT stripper via a subsea stripper to seal around the CT and isolate a section of the wellbore that extends between the CT stripper and the closed safety valve;
isolating pressure in the space between the PCE and the safety valve, wherein the pressure at the wellhead remains at a reduced level;
passing fluid via the CT into the section that extends between the CT stripper and the closed safety valve to reduce a pressure differential across the safety valve while the CT stripper remains closed;
opening the safety valve;
gravity feeding the CT past the safety valve while the CT stripper remains closed to seal the wellbore and maintain pressure;
pulling the CT out of the wellbore; and
lubricating the CT in a section of tubing between the safety valve and the pressure control equipment.
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