AIM & Subsea IRM.

Integrity Management & Inspection Repair and Maintenance are crucial to safety, environment and life of field

The Talisman Subsea IRM philosophy forms an integral part of the asset maintenance system with a data base for procurement and spares strategy linking the IRM management to the subsea asset standards into the Asset Integrity Management System (AIMS)

The purpose of the philosophy is to underpin the conceptual approach for ensuring integrity of the subsea facilities and pipelines and includes the following principal steps.

• Identification of Threats or Hazards.
• Assessment of Risk and Integrity.
• Mitigation and Control.
• Implement Lessons learned.

The philosophy will describe a conceptual approach for ensuring safety and integrity, translated into specific activities under cover of guidelines and recommended practice for the Integrity Management of Submarine Systems for all of the subsea facilities.

Monitoring and control systems for the subsea assets. Topsides controls, instruments and valves used for control monitoring and emergency shutdown (ESD) of the subsea facilities and dry tree top side facilities, first line of response to operational incidents in terms of detection, isolation and depressurisation. Pressure relief devices as applicable and secondary protection in the event of over pressurisation, high integrity pressure protection system (HIPPS) Topside elctro hydraulic operational and chemical injection controls, DTS systems, pigging and chemical injection mitigation measures for waxing and hydrates.

Ensuring first that subsea facilities integrity encompasses an inspection repair and maintenance (IRM) program that becomes a part of the facilities management system. Integrity Management for the assets will focus on the hardware and procedures that are critical for prevention, detection, control and mitigation of hazards and incidents.

Inspection– of the subsea equipment is required on a regular basis in order to determine if any maintenance is required. The frequency of which is driven by recommended practice for the Integrity of Submarine Pipeline Systems. If an event occurs depending on severity that may have an operational or environmental issue, an inspection operation should be mobilised.

Repair– of subsea equipment typically requires the assistance of IRM specialist contracting organisations versed in offshore intervention techniques.

Maintenance – All of the subsea equipment shallow or deep water is either ROV or diver accessible and all maintenance requirements are dependent upon inspection results. Some diagnostic work should be done in the form of routine pipeline maintenance and pig runs with an element of intelligent PIG runs.

The Maintenance Strategy needs to ensure that threats and potential risks are considered in the identification and assessment process. Additional threats may be derived from appropriate review sessions and analysis such as HAZID, HAZOP, and QRA which will determine the strategy. The risk focus for inspection repair and maintenance is comprised of relevant hazards and threats considered in terms of the likelihood of occurrence times the consequence of a risk materialising. The general threats to the integrity of the subsea facilities/assets are concentrated in the main areas listed below.

A Reliability Centered Maintenance (RCM) approach enables maintenance needs of the subsea systems to be determined by a systematic analysis of asset function, criticality, failure mode rate and consequence. The application includes the creation of a failure mode and effects analysis (FMEA), identifying the failure characteristics and likelihood of incidence and the appropriate mitigating action to deal with the consequences of any failures and maintenance.

• A pipeline leak which may cause a shut-in.

• A subsea leak in the production system causing a hydrocarbon release/oil spill

• Choke failure.

• Subsea Control Module failure.

• Chemical Injection failure.

• Topside safety failure HIPPS.

• HS Gas Leak during planned maintenance routines and pipeline internal pig runs.

• Pipeline/wellhead Hydrate/Wax formation.

• Flexible Pipeline Failure, internal corrosion, sheath, end terminations, gas vent valves.

• Riser or J Tube failure, corrosion, supports, clamps or impact.

• Control umbilical failure, incident, impact or anchor.

• Rigid Pipeline failure, corrosion, structural, material, natural hazard.

• SCSSV/Underwater Safety Valve (USV) failure.

• A pig that becomes stuck in the flowline.

• Flow line damage flexible/rigid incident, impact or anchor.

• TUTU, SUTU, SCM Failure.

• MAF, SF, FBHT, Completions plug failure.