Asset Integrity Management and the Dilemma of maintenance planning
The planning and optimization of maintenance programs can be a complex and difficult task for managers of pipeline network operations as well as for their maintenance personnel due to a possible lack of component data, information and decision variables. Maintenance programs and schedules for such installations cover preventive and periodical actions (e.g. internal & external inspection, damage repair, etc.) as well as storage of important spare parts. These measures have an essential impact on the reliability, availability and safety of the infrastructure and on the overall efficiency and availability. In order to prevent unplanned downtimes due to component malfunction and inappropriate and ineffective maintenance programs, a quantitative decision basis is needed to develop such programs. Some of the key input data for the maintenance program are: - Data review of e.g. pigging results with full assessment of indication regarding remaining lifetime assessments. - Monitoring of plant data (e.g. compressor stations) and early indication of required maintenance. - Incorporation of Incident Investigation results to track “online” condition and subsequent actions. In addition to obligatory inspection and maintenance actions based on legislative requirements (e.g. German Fernrohrleitungsverordnung) there is some room to choose different maintenance strategies (such as condition, reliability or risk based approaches) in order to optimize the maintenance program based on a systematic risk based planning process. The objective of this paper is to describe an approach how to utilize existing data and gain further information from pipeline and plant data and establish a more reliable and complete status to reflect on upcoming actions and to solve the dilemma of maintenance planning. The focus of the paper is not only to derive risk figures for comparison purposes regarding safety, economy and environment, but to show practical conclusions for asset optimization and inspection & maintenance planning.