Explanation: dn2 specification; PN.6MPa pressure, you know; M convex surface; GB/T 9123.1-2 standard.
I want to make it clear here that the RF they answered is not a convex surface, but this convex surface. M is convex.
Let me tell you about the sealing surface form:
FF: full plane; RF: protruding surface; M: convex surface; FM: concave; TG: tenon and groove surface
If you have any questions, please contact me: QQ:2571866.