Ring gaskets are a flat sealing element, consisting of an inner and outer diameter sized to fit a flange's bore and bolt circle. Ring gaskets sit inside the flange's bolt circle. ASME B16.21 and ASME B16.47 govern the dimensions of ring gaskets for standard and large diameter pipe flanges. Teadit Tealon TF 1590 is a restructured PTFE material filled with silica and meets a wide range of aplications. It is suitable for general service, strong acids and moderate caustic solutions. It meets FDA conformance for service within food and pharmaceutical applications. TF 1590 has easily passed the Hot Compression Test with outstanding results.