Mooring failures and what to do about them

An MIM plan means that the operators: 

Know the present and future status of their assets through inspections and monitoring: 

• Regular inspections show weakened/damaged mooring components
• Analytical modeling helps identify and evaluate critical/high-risk components
• The life expectancy of the asset can be estimated, based on the actual condition (measurements), degradation rates (inspection records), known metocean conditions, anticipated loading conditions, and resulting and expected fatigue damage 

Be prepared to take necessary actions to maintain production: 

• Develop mooring repair procedures for readily available or spot market installation vessels (e.g., Anchor Handler Vessels, Construction Support Vessels, etc.)
• Identify long lead items, capable installation vessels, installation aid requirements, staging and mobilization locations, import and export restrictions, etc.
• Procure, fabricate, store, and maintain spare mooring components needed to repair or replace failed moorings.
• Perform preliminary installation analyses to identify critical aspects of offshore operations

Take action to document as-built/baseline inspection information and maintain, repair, and replace moorings: 

• Plan and allocate the right personnel to perform inspection, maintenance and repair work
• Stage and mobilize inspection equipment and/or spare components for offshore operations
• Implement the Mooring Repair Plan that is already in place if necessary 

Provide evidence of good IM practices and data management to satisfy safety and insurance requirements for ongoing production operations and earn life extension approval from regulatory bodies: 

• Provide baseline/as-built information and equipment certifications
• Demonstrate a well-planned and documented inspection and maintenance plan
• Provide results and findings from regular maintenance and inspection work
• Estimate degradation rates (e.g., corrosion, abrasion, wear, etc.) based on baseline and regular inspection results
• Identification of any critical/high-risk components that should be monitored or measured more frequently
• Demonstrate preparedness for mooring system damage or failure 

Mooring failures are not inevitable. A detailed mooring integrity management plan can help identify potential maintenance needs, make necessary inspection schedule recommendations, and enable operators’ preparedness to ultimately reduce costs from any unforeseen circumstances.