api 5000API Recommended Practice 500, 4th Edition. API has published API Recommended Practice (RP) 500, Classification of Locations for Electrical Installations at Petroleum FacilitiesAPI 6A TYPE 6B 5000 PSI Blind pipe flanges are used to seal the end of a piping system or pressure vessel openings to prevent flow.API 6A TYPE 6B 5000 PSI Blind flanges are mainly used for pressure testing the flow of liquid or