Jack Up Suitability for South China Sea Sites

Abstract

The decision to use a particular type of Jack Up for a particular site is guided by site specific assessment requirements. The offshore oil and gas industry is guided by ISO 19905–1 and also SNAME 5–5A but since the industry is subject to many varied requirements of marine warranty surveyors, competition between rig owners and urgency of rig usage, operators such as Petronas Carigali Sdn Bhd (PCSB) are at times confronted with technical aspects of site specific assessments that are not trivial to rationalize in terms of selecting Jack Ups that are suitable and fit for purpose for any particular site. Taking into consideration PCSB considerable amount of soil and shallow seismic survey data and accounting for the expected increase in rig utilization in the next five years in the region, PCSB is embarking on a project to provide regional mappings that can provide a tool for assessments of suitability of jack up from a risk mitigation perspective. This paper will present the basis for establishing the need to provide a regional mapping for suitability of Jack Ups by investigating aspects of actual versus predicted leg penetration analyses, jack up structural aspects, geohazard assessments and relating to failure experiences to postulate that jack up rig failures can be mitigated by a risk assessment and mitigation framework. PCSB involvement in an in house study makes it amongst the first oil and gas operators in the region to benefit from its accumulated jack up related experiences and knowledge of soil data in various South China Sea sites. This paper will outline the benefit of having a regional Jack Up suitability mapping in minimizing potential jack up failures thus optimizing operational costs.