Deformable material (or combination of materials) used to prevent leakage of fluid between two surfaces.
Source: API Standard 2RD, Dynamic Risers for Floating Production Systems, Second Edition, September 2013. Global Standards
Deformable material (or combination of materials) intended to be clamped between flanges to prevent leakage of fluid.
Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards