Evaluation of Pipe Flange Connection Assembly Efficiencies Using Common Tools and Patterns

ASME PCC-1 (2010) introduced 5 different alternative bolting patterns in contrast to the Legacy Pattern that is commonly known as the “Star Pattern”. For the past 15 years, research has shown that these Alternative Patterns issued by PCC-1 are more efficient than the Star Pattern. However, the research has shown tool movement around the flange to show efficiency, but not actual assembly time and/or assembly time savings from each one of these alternative bolting patterns. While all of these alternative bolting patterns are not appropriate for every gasket type and might not add efficiency for smaller diameter flanges, there are many mid-stream and downstream petrochemical applications that could benefit from further knowledge of these efficiencies. The goal of this paper is to not only determine which one of these alternative patterns is the most efficient but to also compare different types of assembly tools with each pattern. This analysis does not address the accuracy and repeatability of each method and tool type, but its function is to determine the optimum combination of tool and pattern selection to decrease downtime and Lost Profit Opportunity (LPO). This paper will use both bolting patterns and assembly tools on an 18” 600 Class flange, that has (24) 1-1/4” studs to develop a method for determining further testing of bolting pattern and bolting tools.