Centrifugal pumps: whether to use flange taps for pressure gauge connections

[mrev23]

When is it recommended, or not, to use the flange taps provided by a pump manufacturer for connecting pressure gauges?

The detail at the link below shows one gauge connection to the flange tap on the suction side of the pump; the other is downstream of the flex connector on the discharge side of the pump:

http://orf.od.nih.gov/PoliciesAndGu...Mechanical/M-E4-1_End Suction Pump M-E4-1.jpg

Connecting the other side of the flex connection could protect the gauge from some vibration; but:
1. How important is this amount of vibration isolation?
2. It requires additional labor and material to create and use gauge connections other than those provided by the manufacturer.

In the configuration shown in the detail linked above, the pipe between the suction flange and the gauge bridges across the flex connector. This would seem to subject the gauge at the top of the riser to vibration from the suction flange; the vibration isolation from the discharge flange seems to be negated.

Why not use the flange taps provided by the pump manufacturer for pressure gauge connections?

 

[EnergyProfessional]

You probably should talk to the agency that seems to have published this. It is a bit dated anyway judging by the fact it uses a balancing valves. It is 2015 and we use VFDs nowadays...

you raise some good points. I wouldn't worry about the small 1/4" pipe for the gauge transferring any vibration. that thin pipe itself is flexing. under normal operation he pump shouldn't vibrate anyway. I also would get rid of butterfly valves and use ball valves.