Take for extra pressure protection devices, Flange connecting dimensions of comply with standard series one and two of JB/T2769-94. These safety valve are used for the equipement and pipeline of the steam, etc. medium what the working temperature with C type are less than 425 Celsius degree and I type are less than 500 Celsius degree . and V type are less than 550 Celsius degree. For more info,please contact us at any time!