If the safety valve data sheet indicates an opening pressure of 8.5 bar (a), should the calibration pressure for opening be 7.5 bar (g) ??

 

so is 1 barg = 1 bar?

I say if the system works at 1 barg it means the absolute pressure is 2.
Abs Pressure = Gauge Pressure + 1 atmosphere
Abs Pressure=1 bar+1.01 bar (which is 1 atm)
Abs pressure= pprox. 2 bar or approximately 2 atm.

 

i have one question,
how to convert barg to bar?

e.g : 1barg = ?bar

you will add 1 atm pressure to 1 barg and see the absolute pressure will be 2 appx. in bar or atm unit.