Pump Head Calculation

I would call the manufacture of the flexible joint being used. Or the manufacture of the chiller unit for the data on the unit that was used by them. I your firm is designing unit then talk with the supplier of the flexible coupler. They will have data on their materials being supplied by them. If not find another supplier.

Somewhere between 0.01 and 0.1 psid, as a rough guess. If it is the same i.d. as the pipe to which it connects, just add its length to the pipe length.

I agree with Tornado ..... but I don't understand why this is significant in a pump head calculation.

Remember people, you are calculating design conditions for a centrifugal pump. You are not building a watch. All pump head calculations are, by thier nature + or - 10%.

In relationship to this approximate calculation, you must remember that the pressure drops through expansion joints are "chump change"....