Due to harsh winter weather conditions, oil field operators in the North Sea typically schedule oil platforms and other infrastructure repairs and maintenance during the summer months. This does not cover the entire range of maintenance tasks needed to maintain a platform. There is also a need to perform corrective maintenance from failure events which are unscheduled and of random occurrence.
From a modelling perspective, in the majority of cases it is adequate to define a single repair distribution to cover the repair time for the entire system. However, in some cases such as the scenario aforementioned and others like subsea repairs or extreme environments, the repair distributions may have wide seasonal variations.
To accommodate this need, a method of defining seasonal distributions has been introduced to the Maros software for RAM analysis in the upstream oil and gas industry. Seasonal distributions may be used for the repair parameter of unscheduled failure modes, scheduled elements or conditional elements.