... -94,SY/T6143-2004,ISO 5167-1,AGA Report No.3 etc standards. 2,Patent structure for orifice plate allocation, ... precision, the discharge coefficient is superior than Grade 0.5. 3,ENP on orifice plate, guide plate, etc trims, prefect corrosion ... medium, can be divided into non-sulphur resistant type, sulphur resistant type.9,Product range:PN1.6~32MPaDN50 ~700mm Simple Type Orifice Meter Fitting