Remote wellhead integrity and sub-surface safety valve test

A system for remotely testing wellhead integrity of a well, the system comprising:

• a memory;
• and
• a computer processor connected to the memory and that:
• obtains real time pressure and temperature readings of a plurality valves and associated gauges of a wellhead of the well, the wellhead comprising a T-shaped junction where a wellbore terminates at the Earth's surface and hydrocarbon production flows from the wellbore into a flowline along a downstream direction from the T-shaped junction;
• detects, based on images from a thermal infrared camera installed at a wellhead tree and flow lines of the well, potential oil/gas leaks;
• and
• determines, based at least on the real time pressure and temperature readings and a detection result of the images, integrity of the plurality of valves,
• wherein the memory and the computer processor are part of a supervisory control and data acquisition (SCADA) system remote from the well,
• said plurality of valves and associated gauges comprising:
• a well cap at the top of the wellhead for controlling wireline access to the wellbore;
• a crown valve (CV) disposed between the T-shaped junction and the well cap for further controlling the wireline access to the wellbore;
• a pressure gauge (PG) disposed between the well cap and the CV for measuring a wellhead pressure;
• a master valve (MV) disposed between the T-shaped junction and the wellbore for controlling the hydrocarbon production from the wellbore;
• a subsurface safety valve (SSSV) disposed below the MV for safety closure of the wellbore,
• a wing valve (WV) disposed between the T-shaped junction and the flowline for controlling the hydrocarbon production into the flowline;
• a choke valve disposed in the flowline downstream from the WV for flow restriction of the hydrocarbon production;
• an upstream pressure transmitter (UPT) disposed in the flowline between the WV and the choke valve for measuring pressure data before the hydrocarbon production passing the choke valve;
• a downstream pressure transmitter (DPT) disposed in the flowline downstream to the choke valve for measuring the pressure data after the hydrocarbon production passing the choke valve;
• and
• a block limit valve (BLV) disposed in the flowline downstream to the DPT for isolating the flowline from the wellhead;
• said obtaining real time pressure and temperature readings comprising:
• closing, in response to a first control signal from the SCADA system, the SSSV, the MV, the WV, the CV, and the BLV to record an initial downstream pressure using the DPT;
• opening, in response to a second control signal from the SCADA system, the SSSV, the MV, the WV, and the CV while keeping the BLV closed to record an initial shut-in wellhead pressure (SIWHP) using the PG;
• and
• validating gauge accuracy by comparing gauge readings of the PG, the UPT, and the DPT, and
• said determining the integrity of the plurality of valves comprising:
• determining that the BLV is holding by at least monitoring and comparing the gauge readings of the PG, the UPT, and the DPT with respect to the SIWHP throughout a first pre-determined time period.

A non-transitory computer readable medium (CRM) storing computer readable program code for remotely testing wellhead integrity of a well, wherein the computer readable program code, when executed by a computer, comprises functionality for:

• connecting a plurality valves and associated gauges of a wellhead of the well remotely to a supervisory control and data acquisition (SCADA) system, the wellhead comprising a T-shaped junction where a wellbore terminates at the Earth's surface and hydrocarbon production flows from the wellbore into a flowline along a downstream direction from the T-shaped junction;
• obtaining real time pressure and temperature readings of the wellhead through the SCADA system;
• detecting, using a thermal infrared camera installed at a wellhead tree and flow lines of the well, potential oil/gas leak;
• and
• determining, by the SCADA system and based at least on the real time pressure and temperature readings and a detection result of the thermal infrared camera, integrity of the plurality of valves,
• said plurality of valves and associated gauges comprising:
• a well cap at the top of the wellhead for controlling wireline access to the wellbore;
• a crown valve (CV) disposed between the T-shaped junction and the well cap for further controlling the wireline access to the wellbore;
• a pressure gauge (PG) disposed between the well cap and the CV for measuring a wellhead pressure;
• a master valve (MV) disposed between the T-shaped junction and the wellbore for controlling the hydrocarbon production from the wellbore;
• a subsurface safety valve (SSSV) disposed below the MV for safety closure of the wellbore,
• a wing valve (WV) disposed between the T-shaped junction and the flowline for controlling the hydrocarbon production into the flowline;
• a choke valve disposed in the flowline downstream from the WV for flow restriction of the hydrocarbon production;
• an upstream pressure transmitter (UPT) disposed in the flowline between the WV and the choke valve for measuring pressure data before the hydrocarbon production passing the choke valve;
• a downstream pressure transmitter (DPT) disposed in the flowline downstream to the choke valve for measuring the pressure data after the hydrocarbon production passing the choke valve;
• and
• a block limit valve (BLV) disposed in the flowline downstream to the DPT for isolating the flowline from the wellhead;
• said obtaining real time pressure and temperature readings comprising:
• closing, in response to a first control signal from the SCADA system, the SSSV, the MV, the WV, the CV, and the BLV to record an initial downstream pressure using the DPT;
• opening, in response to a second control signal from the SCADA system, the SSSV, the MV, the WV, and the CV while keeping the BLV closed to record an initial shut-in wellhead pressure (SIWHP) using the PG;
• and
• validating gauge accuracy by comparing gauge readings of the PG, the UPT, and the DPT, and
• said determining the integrity of the plurality of valves comprising:
• determining that the BLV is holding by at least monitoring and comparing the gauge readings of the PG, the UPT, and the DPT with respect to the SIWHP throughout a first pre-determined time period.