BY RAMESH SINGH
A maintenance strategy based on risk is a suitable approach for all types of assets from refinery plants to pipelines. Risk is defined as the sum of the probability of failure (PoF) and the consequence (CoF) resulting from that failure. The strategy provides a systematic approach to determine the most appropriate asset maintenance plans. Upon implementation of these maintenance plans, the probability of asset failure will be reduced to an acceptable level
Asset integrity is a growing subject of concern to corporations as poor integrity of assets adversely affects safety, operating costs, the environment, and potentially the corporate image. The total cost of the consequence is the most effective and prime motivator for action.
HOW CAN YOU ENSURE SAFE, RELIABLE, AND PROFITABLE OPERATIONS?
Several concepts and specialized integrity programs are developed and practiced to improve the reliability of assets. Most of these practices are primarily based on the existing practices of data collection, analysis, and prioritizing the inspection and maintenance activities. They all depend on the same tools and principles, like HAZOP, FMEA, FTA and RBI that have been in use over the years.
The primary objective of all such concepts is to develop an integrity maintenance strategy to reduce the PoF and CoF of high to medium to low risks. The maintenance strategies are optimized so that the functionality of the asset is maintained using cost-effective techniques. The critical points of such program can be surmised as follows:
• The primary objective is to preserve system integrity. Preservation of system integrity requires that damage mechanisms are thoroughly identified.
• Damage mechanisms are then used to calculate a probability of damage and failure. Combined with the CoF, total risk can be calculated.
• Strategies are then developed to address high consequence areas using the appropriate inspection and mitigation techniques suited to each damage mechanism.
• Periodic reviews of the strategy and results are required to optimize the asset integrity plan for each component within the system
The end goal of any asset integrity program is to focus integrity resources on the highest risk areas using the appropriate methodology to increase safety and reduce risk, coupled with reliability and maintenance programs. The end result is an asset that provides maximum safety, revenue, and asset availability. The successful management of any asset integrity program is based on continuous evaluation, like verification audits, and repeated validation. The Site Managers must periodically ask themselves “Is the asset safe and reliable?” This question can be adequately validated if answers to the following are satisfactory:
• What are the functions and desired performance standards of each asset in the system?
• How can each asset fail to fulfill its functions?
• How is the performance standard measured?
• What should be done to predict or prevent each failure?
• What should be done if a suitable proactive task cannot be determined?
Once the questionnaire is prepared and responded to, gather a team to perform an analysis and make recommendations for integrity implementation. The implementation should be planned in gradual steps.
After implementing the asset integrity program, it is essential for its success to regularly measure, review with program health assessments, and if necessary revise the tactics relating to changes in plant design, operation, nearby population changes, and even regulations updates
An integrity program based on risk is a suitable approach for all facilities and pipelines. It provides a systematic approach to determine the most appropriate asset integrity plans. Upon implementation of these plans, the overall risk will be reduced thus improving safety.
Asset managers that don’t have these integrity strategies in place within their organizations should take immediate steps to correct their risk management program and mitigate those risks as soon as practical. Your corporate image demands it, regulations require it, and your stock holders will benefit from it. Contact G2-IS today to see how you can benefit from our Asset Integrity Services..
Ramesh Singh, Pipeline Integrity: Management and Risk Evaluation, 2nd Edition ELSEVIER Publication, ISBN 978-0-12-813045-2
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