What are gasket constants?

The ASME and ASTM committees are working on a new system and new set of numbers to be used in the ASME code calculations for flange design. These new constants (also known as Gb, Gs, and a) address leak rates at installation and during loss of compressive load and therefore are meant to help end users design for a certain leak level. The use of a defined leak rate will often generate higher bolt load requirements for the flanges, which should improve performance of designed joints. For gasket constant values, see Engineered Gasketing catalog.