| dc.description.abstract | Design of process modules, piperacks and occupied structures for accidental fire loads is critical for a facility’s operation, emergency planning, safe shutdown and evacuation strategy. In the oil and gas industry, hydrocarbon fire scenarios with high thermal loading should be accounted for. These accidental fire loads can be critical during the design phase. Recent improvements in fire analysis and design methodology for structures, piping systems and equipment are discussed in this study in regard to performance-based applications. Acceptance criteria for performance-based fire design have not been well documented in the literature. Prescriptive approach, utilization checks, limiting core temperatures, and deflection ratios or plastic strains for ductility level analysis are used as the basis of fireproofing requirements in the industry typically. However, actual response of safety critical elements supported by the subject structural members is typically not taken into account directly. Different acceptance criteria and response of supported piping systems are presented through case studies in this paper. Also, practical aspects of fire protection including three sided PFP application and coat-back optimization are discussed. For the structural fire integrity assessment, heat transfer and structural fire response analyses were performed utilizing USFOS and ABAQUS software packages. Performance-based approach in fire response design of offshore and onshore structures has been successfully implemented using advanced numerical analysis tools and close collaboration between Safety, Structural, Construction and Operations teams. This approach involves an iterative analysis procedure considering interaction of load bearing (structural) and other systems (piping, electrical etc.). The refined analysis and optimization process ensures that PFP is only applied to critical structural elements and fire performance of protected systems are verified through analysis. In addition to reducing the risk, this in turn precludes an overly conservative design recommending application of PFP in a broader area without analytical justification. The main advantages of reducing application of PFP coating on non-critical members and equipment are cost savings and integrity management improvements during life cycle of a facility due to issues such as corrosion under insulation and long-term inspection and maintenance. Considering the fact that CAPEX and integrity management are major concerns for most structures at petrochemical facilities, optimization of PFP for plant structures has significant benefits for operators and owners of onshore and offshore assets. The integrated structural, foundation and equipment and piping systems fire analysis approach presented in this study is considered to be a significant addition to state of the art in fire protection design of oil & gas and petrochemical facilities. Improvements in analysis and design methods are expected to result in application of PFP at the critical locations only without compromising from safety requirements. This also ensures that safety critical elements are protected against credible hydrocarbon fire scenarios. | en |
