A Critical Understanding of “Low-Stress” Spiral Wound Gaskets

Abstract

Low-stress spiral wound gaskets are marketed as an alternative to standard spiral wound gaskets, requiring less torque to seat the gasket. Spiral wound gaskets are common commodities used in piping reliability staff are constantly looking for different alternatives. Multiple manufacturers offer a low-stress version of spiral wound gaskets. Do these spiral wound gaskets offer a low-stress solution, and do they perform better than a standard spiral wound gasket? This paper will go beyond the marketing of “low-stress” spiral wound gaskets and examine the construction and engineering behind these gasket designs. Manufacturers of spiral wound gaskets have made subtle changes and the “low-stress” technology has become a common theme throughout the spiral wound gasket market. Multiple chemical and petrochemical plants use these designs in their piping systems and sometimes as replacements for ASME recommended spiral wound gaskets with inner rings. Low-stress spiral wound gaskets have multiple designs from additional graphite in the filler to an anti-buckling design which are marketed as requiring less initial preload to seat. This paper will examine the validity of these gaskets and determine if they are low-stress and if they provide a credible seal in a bolted flanged joint. [1]