Using raised face flange with flat face
Using raised face flange with flat face
(OP)
To save time and money is there a safe way to bolt a 150# rf flg to a 125# ff. The service is cooling water and chill water, bolting an instrument to a valve, less than 100degF and 80psig operating parameter. Is there somewhere that it is written that I could go too to print out. I have heard of double gaskets and changing bolting material.





RE: Using raised face flange with flat face
RE: Using raised face flange with flat face
The way I have always done it is to have the raised face of the 150# flange ground off so that the mating surfaces are flush. It is quite a bit of work. Sometimes is is easier and cheaper (depending of pipe size) to match the 150# flange with a 150# flange. I am guessing that your instrument has the 150# flange. In the case of non-ASME code water piping, it has always seemed easier to me to direct the contractor to match whatever flange he needs to match.
If you are connecting to a cooling tower, the balancing valves and the outlet connection usually need a flat faced flange. Another cheap solution in these pressures and temperatures is an angle face ring and ductile iron back up flange. They are cheap and require a full face gasket!
RE: Using raised face flange with flat face