A common misconception with any pump, for that matter, is that the flow rating of the pump is the output that a user will see - regardless of the plumbing system that the pump is installed into. For further explanation check out one of our previous blog posts about centrifugal pump sizing, applications and how a plumbing system affects pumps differently.
While most 12 Volt fuel pumps are not centrifugal pumps the flow rates of these pumps is still drastically affected by the plumbing systems in which they are introduced into. Think of it this way - while your car speedometer maxes out at 160 mph you certainly can't drive the vehicle that fast - at least for an extended period of time without catastrophic failure. A pump is very much the same - while it may be rated to 25 gallons per minute (GPM) that doesn't mean that you will see flow rates equivalent to that output.
One solution to decrease filling times is to evaluate your plumbing system. Do you have 3/4IN lines? Can you bump up to 1IN? Remember, the greatest thing we can do in order to increase the efficiency of our plumbing system is to increase the size of the plumbing system. How about a high flow fuel nozzle?
If we simply have a standard flow nozzle that will certainly affect your flow rates in a negative manner. Keep in mind that many 12 Volt transfer fuel pumps from manufacturers such as Fill-Rite or GPI are rated 20-25 gpm. Now if you have nozzle at the end of your plumbing system that is rated only to 20 gpm don't think that your 25 gpm pump is going to achieve that flow rate. You have just capped your flow rate at 20 gpm with the limiting factor being the nozzle.
Should you have a 3/4IN line you will see an even greater reduction in flow rates - again the greatest thing one can do to increase the efficiency of a plumbing system is increase the size of the plumbing. Another major plumbing constraint to be aware of is the filter. Ensure your plumbing system has a high flow capacity filter such as Cimtek's CI1000.
What can one do to drastically reduce filling time in the field or at the farmstead? Invest in a high flow transfer unit such as our DUFPU1.5P. This unit has been tested to 60 gpm. Check out another blog post dedicated to this unit here. This can cut your fill times by 1/3 of the time it takes to fill using a standard 12 Volt pump or gravity feed elevated tank.
Simple fact - that means less downtime for you and more time in the field - ultimately equating to greater profitability. For those wanting a simplistic engine driven diesel fuel transfer pump check out these 5.5HP - 11HP options. Remember we can go slightly lighter on the horsepower requirements when pumping a material such as diesel fuel.
This is due to the fact that diesel fuel actually has a lighter specific gravity than water (8.34 lbs/gal) and, therefore, we can use less horsepower to achieve the desired flow rates. We will have a blog post on specific gravity and how that correlates to product flow rates at a later date. Stay tuned...
