Gasket Dimensions for ANSI Flanges 012004-008 Thermoseal Inc. Phone: 937-498-2222 2350 Campbell Road FAX: 937-498-7544 Admin. Sidney, OH 45365-9573 FAX: 937-498-4911 Sales Gasket Dimensions for ANSI Flanges RING GASKETS FOR 150 LB. CLASS ANSI PIPE FLANGE RING GASKETS FOR 300 LB. CLASS ANSI PIPE FLANGE Nominal Pipe Size Gasket I.D. Gasket O.D. Nominal Pipe Size Gasket I.D. Gasket