Select Page

How to Calculate Maximum Operating Pressure from Rod Load

PMAX = FRL × 4 / (DP2 × π)


PMAX = Maximum Operating Pressure* in pounds per square inch
FRL = Rated Maximum Rod Load in pounds
DP = Plunger Diameter in inches
π = Pi = 3.14159

Maximum Operating Pressure [PSI] = Rated Rod Load [Lbs] × 4 / {(Plunger Diameter [in])2 × 3.14159}

Rated Rod Load = 10,000 Lbs
Plunger Diameter = 6.5 Inches
Calculate: 10,000 [lbs] × 4 / {(6.5 [in])2 × 3.14159} = 301.36 PSI

*The maximum operating pressure calculated here is for the power end only. The maximum operating pressure calculated from the rod load should be compared to the fluid end’s maximum pressure. A check valve should always be correctly installed and set for less than the lower of the maximum operating pressures for the fluid and power ends of a pump.

These calculations and the information provided on this page is for reference only. Power Zone Equipment is not responsible for errors or incorrect caclulations when applied to real life projects. Please use this information with care. For engineering assistance and design of equipment systems, please contact Power Zone Equipment.

Power Zone Equipment's Services


Engineering and design services for equipment


Research and Design systems for equipment and product testing


Industrial equipment testing and design confirmation


Rebuilding Services for pumps, blowers, and motors