Integrity management process starts with inspection. However, this is the proper interpretation of the inspections results and mitigation planning and repairs which is key for effective integrity management. Utilizing an industry approved standard for inspection and interpretation of the results is the best way to maintain the fitness of in-service equipment for continued use and Fitness for Service (FFS) is the standard and best practice used in the oil and gas industry.
FFS assessment is a quantitative measurement of the structural integrity of a component which might contain flaws. Such assessments utilize standards that act as guidelines which help plant managers in decision making process and identification of appropriate mitigation actions to ensure the safety of the in service components.
FFS is used in a range of industries to support design, fabrication, operation, change of service and life extension programmes. Industries such as oil and gas, power generation, chemical processing and aerospace benefit from FFS inspection techniques and they utilize it as part of the plant lifetime management process, to confidently increase availability, reliability, efficiency and safety.
Why use Fitness for Service?
The loss of manpower and production due to unplanned shutdown of a process plant or manufacturing unit is a heavy cost to the companies. The ideal alternative solution for inspection and solving mechanical integrity issues is using Fitness for service assessments. Normally, the screening assessments if carried out correctly, can determine if equipment is safe for immediate return to service. Even though, higher levels of assessments can be more complex and time consuming, however, in comparison to replacement of the equipment they can save lots of time from the ordering, supply and commissioning stages.
Fitness-for-service assessments are the appropriate method for evaluation of the structural integrity of components and their fitness for continuous service. Procedures such as BS 7910:2013, API 579/ASME FFS-1, ASME B31G, DNV-OS-F101 and FITNET enable the integrity of critical pressure components and welded structures to be assessed against different failure modes, using a validated engineering approach.
Benefits of Fitness for Service assessment
Fitness for service assessment reports can provide businesses a comprehensive overview of a component or plant’s conditions. It also acts as a supporting evidence of compliant to codes and regulatory requirements. It also can be regarded as a proof for reliability and safety of a pipeline.
Reports may also include indications of remaining life of an asset, satisfying a client’s commercial needs and the regulations of a governing body while also paying proper respect to safety and operational requirements.
To summarize, the most important benefits of utilizing Fitness for Service inspection are:
- Support design, fabrication and operation
- Plant life management
- Improve equipment availability
- Optimise maintenance and inspection scheduling
- Improve equipment safety
- Determine equipment residual life
- Integrate lessons learnt from previous equipment failures
- Life extension programmes
- Re-rating or operation change
Applications of Fitness for Service
The important outcome of the Fitness for Service assessments are the reports which are used by the operators to verify the current conditions of the assets, planning of the future actions and compliant to the codes of conduct to provide as a proof to the governing bodies. The assessments are conducted for variety of defects and are utilized in various industries including:
- Oil and gas pipelines
- Power generation industry
- Pressure vessels
TWI SEA Fitness for service assessment services include:
Our experts are highly experienced in the development and application of FFS techniques, particularly for the avoidance of brittle and ductile fracture and also general and local metal loss. TWI can help solve problems that may arise throughout the lifecycle of a component – from design to decommissioning – minimising risk and cost.
Through established multidisciplinary teams, with specialist knowledge in areas of fracture mechanics, fatigue, finite element analysis, materials, inspection and welding, TWI has carried out FFS assessments on pressure vessels, slug catchers, storage tanks, pipelines, piping system and high-temperature equipment in accordance with industry-accepted standards.
Assessment services will take your inspection results and tell you whether the immediate integrity of your pipeline is under threat, and when unacceptable defects could appear in the future, allowing for informed and safe repair planning. The cause of defects will be investigated and appropriate mitigation recommended to control future degradation. As partners in managing clients’ pipelines, we make a full contribution to achieving the best results for safe, profitable and responsible operation.
TWI's wide-ranging expertise is regularly used to develop non-standard testing and assessment methodologies, conforming to the API 579/ASME FFS-1 Level 3 classification. This capability allows us to take on and solve problems where non-standard geometry, unusual loading, or exotic materials mean that standard FFS approaches are unsuitable.
TWI's expert staff are also available to conduct FFS training, either through our in-house training school or as a bespoke programme, tailored to the needs of individual clients. FFS assessment offers a comprehensive analysis of a pipeline’s current and future integrity. It sets out for our clients a clear program of repair, inspection and mitigation actions, which, when scheduled and completed, ensure safety and reliability.