Solutions for Wellhead Integrity Challenges Today
Well integrity assurance is a fundamental need throughout the lifecycle of all wells. Definitions vary, but the universally adopted rule to facilitate this is:
"At least two tested independent (primary and secondary) barriers between a hydrocarbon source and the environment shall exist at all times".
Well Integrity Management
It has been reported that Sustained Annulus Pressure (SAP) is a challenge in over 40% of today’s global well stock. Many wells are prematurely shut in as a result.
Most commonly the SAP is un-planned, and a result of down-hole completion, casing or cementation failure. In other cases, where lift gas is being injected or vent gas is being produced via the annulus, the SAP is planned. Irrespective, both scenarios pose a significant risk to personnel and facilities as the double barrier rule has been compromised in these wells. Specifically, the wellhead outlet valves, ring gaskets, instrument flanges and pressure gauges provide only a single barrier between the hydrocarbon source and the environment.
Reliable data and continuous monitoring of the annulus with SAP and its outer counterpart is critical for safe operations. A method for the safe management and bleed off of pressure in the event that it approaches the casing or tubing design limits is also necessary.
Historically, there were no solutions to these challenges. PTC have now developed unique technologies, which fully address the issues. These are now field proven and increasingly adopted by OPCO’s worldwide.
Annulus Pressure Monitoring Technologies
PTC's unique VR Sensor System is installed in the wellhead VR profile. It enables continuous and reliable annulus pressure and temperature (P&T) monitoring, thus enhancing well integrity. The system eliminates the need for wellhead gate valves and instrument flanges. Furthermore, it eliminates the need and cost associated with human intervention. It is also designed to maintain well integrity even upon impact or collision.
Annulus Pressure Management Technologies
PTC’s Master Surface Annulus Safety Valve (MSASTM) is installed in the wellhead VR profile. It can be used as an actuated (fail-safe closed) barrier valve in gas lift applications, or safety / bleed valve in wells where SAP or annulus production needs to be managed.
Autonomous Annulus Pressure Management Technologies
The integration of PTC's VR sensor, Master Surface Annulus Safety Valve (MSAS) and Field Cabinet provides a system for autonomous and controlled annulus pressure management. This system, the A-Pro, can be configured to both autonomous and human intervention modes. The system can be self-sustained or connected to an external power source.