The QSW4 Q-Ger Spiral Wound gasket has both metals outer and inner ring. As inner ring works to prevent internal extrusion or inward buckling, this style is especially recommended for the following cases.
– For flanges NPS 24 and larger in class 900, NPS 12 and larger in class
– 1500 and NPS 4 and larger in class 2500#.
– PTFE filler material.- For socket welding, lapped, welding neck & integral flanges. This style is suitable for pipe or pressure vessels using raised face flange connection.