API flange and API 5000 10000 blind instrument flanges

api 5000API 5000, 10000 are used in reference to wellhead 'christmas tree' pressure ratings as well used for the wing valve, master valve ratings. There may be hher classes asAPI 5K API 5K means an API-defined BOP confuration with a rated working pressure of 5,000 psi and as described in API RP 53, adopted by reference at 20 AAC 25.527(c). Source: Alaska