Gas Field Life Extension
A gas production complex in Southeast Asia including six offshore platforms was built in 1981 with a 20 year design life.
In 2004 the operator commenced a life extension project to provide for an additional 20 year service life from the facilities. The RBI study applied to piping, pressure vessels and heat exchangers on the platform complex. There were 145 Pressure Vessels and Heat Exchangers and 599 Piping Line Tags in 248 Circuits.
An RBI study using the T-OCA software was determined to be the most cost effective method to provide the necessary data for the project because the built in corrosion models in the T-OCA software would provide quick estimates of remaining life.
The work plan included:
- Initial assessment
- Decision to inspect, replace or upgrade
- Inspection
- Reassessment
- Decision on any additional replacements
The results
The design of the T-OCA tool and the RBI process was particularly well suited to this situation with limited availability of data.
The RBI team worked efficiently with the life extension project. The T-OCA software allowed the assessments to be developed quickly and the required information was provided to the project teams within the project schedule.
The final life extension plan for included the following:
- Flowlines, manifolds, piping to separators, export gas piping replaced in carbon steel
- Piping from separators to compression replaced in duplex stainless steel
- Glycol regeneration skids replaced in carbon steel
- Production coolers and condensate coolers replaced in carbon steel
- Numerous local repairs made to high and low pressure piping
