ASME B16.20 pdf download Metallic Gaskets for Pipe Flanges Ring-Joint, Spiral-Wound, and Jacketed 2.7 Identification Number Dimensional reference identification numbers are assigned to ring-joint gaskets and shown in Tables 3 through 8 (Tables I-1, I-2, and I-3 of Mandatory Appendix I). 3 SPIRAL-WOUND GASKETS 3.1 Size and Class Spiral-wound gaskets, including centering ring and inner ring (paras. 3.2.4 and 3.2.5),...