Pipe & Pump Sizing Calculator


    • Tank Fully Above Pump

    • Tank Below Pump

    • Tank Below Pump With Overhead Piping

    • Tank Partially Above Pump

    The storage tank is fully above the centerline of the pump. The piping for this system is above the centerline of the pump. If a leak developed in the line or a valve was unintentionally left open, oil would siphon out of the storage tank. Therefore, the Anti-Syphon Valve is added into such a piping arrangement to avoid any siphoning of oil out of the storage tank.



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Primary Suction Velocity, FPS0.00
Secondary Suction Velocity, FPS0.00
Piping Friction Loss, in. Hg0.00
Fitting Friction Loss, in. Hg0.00
Anti-Siphon Loss, in. Hg0.00
Strainer Friction Loss, in. Hg0.00
Static Lift, in. Hg0.00
Priming Static Lift, in. of Hg0.00
NPSHa (Available), feet of Oil0.00
NPSHr (Required), feet of Oil0.00
Primary Discharge Velocity, FPS0.00
Secondary Discharge Velocity, FPS0.00
Required End Pressure, PSIG0.00
Piping Friction Loss, PSI0.00
Fitting Friction Loss, PSI0.00
Strainer Loss, PSIG0.00
Static Head, PSIG0.00

Fuel Pump & Pipe Sizing Calculator

This pump and pipe sizing tool is applicable for diesel generator and boiler fuel systems. It is based on the use of positive displacement pumps that are sensitive to suction line conditions, so the first couple of screens ask for information regarding the layout of the main tank(s) relative to the location of the pumps. The discharge side of the pumps can feed a boiler loop, or a header supplying multiple generator tanks. Calculations are based on the Crane Flow of Fluids handbook. To speak to a Preferred engineer who knows NFPA fuel codes and is experienced with fuel oil storage and handling systems, call (203) 743-6741.


The goal is to select a pump that meets the flow and pressure requirements of your project, and design the piping system so that the suction on the pump inlet, and discharge pressure at the pump outlet, are within the safe operating limits of the pump. Starting with 1. PIPING LAYOUT, click on the tank/pump configuration that matches your project. Then click on the NEXT: Parameters button and input the required information. Pump suction and discharge pressure are always displayed at the top left of the screen. Green is good. If a red warning box is displayed, click it for more information. Next click on 3. SUCTION PIPING and input the pipe size, length, and valve information required. Investigate every pulldown box because if you miss one, the default entry could put your system in the red. Do the same with 4. DISCHARGE PIPING. Finally, click on 5. SUMMARY to see detailed pipe and valve pressure losses. You can navigate back and forth between tabs, changing selections as you go until you get a pump and piping system that works.


You can save as many projects as you like and come back to them later. Saved projects are associated with your email address. If you have saved work previously and do not see your projects listed in the right column (or at the bottom if you're on a mobile device) then just enter your email address to login and recall your projects. If you are working on a saved project, you will see it's name in the "Project Name" field in the "About this project" section. Changes are not saved automatically! If you change your calculation parameters and want to save the new results, you must click the "save changes" button. To save a new project: enter a value for "Project Name." If you are already logged in, the rest of the information will already be completed, otherwise fill out the rest of the contact fields and click "Save." The project will now be associated with your email addresses, allowing you to work on it again in the future, along with any other projects you have saved.

A Few Notes About Fuel Systems:

--Generators consume about 7 gph of diesel fuel for every 100 kW of output, but the fuel pumps on the generators can flow as much as four times the generator consumption. Depending on how your return piping is routed, supply pumps may need to keep up with generator consumption or with their pump rate. Pump safety factors are relatively high—we want to refill tanks quickly.
--Some burners have on board fuel pumps and some don’t. Read the burner submittal information carefully to determine the flow and pressure requirements of the burners.
--Whenever fuel is stored above the level of the transfer pumps, NFPA requires an anti-siphon valve be installed at the high point in the suction line. This is to prevent a spill in case a valve is left open or there is a break in a low point in the line. When a pump is energized, pump suction overcomes the spring in the anti-siphon valve to allow fuel to flow.
--Many states and cities have local requirements for fuel oil handling or storage. Preferred has engineers in most of these locations. They can quickly answer questions about fuel codes in your area, verify your design, or suggest alternatives. You can reach them by dialing (203) 743-6741.