Flange facings dimensions according to standard EN 1092-1.

EN1092-1 flange sealing surface is divided into ten different types: full plane FF, raised surface RF, convex surface M, concave surface F, tenon surface T, groove surface G, ring joint surface RJ, general concave and convex surface MF, tenon and groove surface TG, Ring connection surface RJ, are paired use. Ring groove face seal face It is often used with butt welding connection type (not with socket welding), mainly used in high temperature, high pressure or both high working conditions. Flanges are commonly used in PN10, PN16, PN25, PN63 (PN series) pressure classes. Raised sealing face It is the most widely used type. Full flat sealing surface It is often matched with the flat welding type to be suitable for mild operating conditions (PNg1.0); it is often used for cast iron flanges or steel flanges connected to cast iron. Concave and convex sealing surface Often used with butt weld and socket styles.

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