What's on Your Engine Company #10 - That Front Suction
By President Mark Davis
February 16, 2023

We often point out the diminished flow ability of a front suction intake on a traditional midship-mount fire pump. In most all cases the reduced flow issue is related to pipe sizing and the elbows (bends) needed to clear the front axle. These photos show a good example of how 5-inch piping was used to plumb the 6-inch front intake back to the lower intake port on the Hale QMax pump. The photos are a simple example showing why drafting from that from suction (5-inch pipe - 20+ feet worth) will produce less flow than using 6-inch hard suction hose from the main suction (steamer) intake. Not necessarily a deal-breaker when operating from a pressurized fire hydrant, and not necessarily a deal-breaker when using multiple suction intakes when drafting....but definitely an issue when used as the only suction intake when drafting.

The video link from Hale does a good job of explaining the discharge and intake options on their QMax pump and the flow abilities of those items. Keep in mind that in order to achieve some of those higher flows it is important to pay attention to the torque available from the vehicle's motor.

Hyperlinks: The Hale QMax Pump