Fuel oil pumping


Gensets are equipped with gear-driven pumps in the engine ‘s common-rail which pressure fuel. The internal pump draws fuel from the tank behind it. The excess fuel which has not been pumped into the cylinders is returned to the tank. The pump has limited capacity in the fuel distribution system (piping, fittings, and filters) for priming and overcoming friction losses.


Two types of electric-driven fuel oil pumps are commonly used outside the genset: gear pumps and centrifugal submersible pumps — each with their own advantages and disadvantages.


Gear pumps: Such pumps may be internal or external gear types, mounted on a separate skid, and usually used for low-flow, high-pressure applications. The gear pumps are known as positive displacement pumps when pressure levels reach 40 psi. In addition, gear pumps with pressure capabilities exceeding 2000 psi are available. The gear pumps are machines with a constant flow rate, and their maximum discharge pressure depends on the power of the motor.


Submersible pumps: Submersible pumps used in high-flow, low-pressure applications need sufficient clearance above the fuel tank for accessibility and maintenance, even though much of the pump assembly is inside the tank. Priming or suction lift may not pose any problems.


During the design of the fuel system, the static lift and friction losses should be investigated in detail. The pumping system’s design flow rate should be two to four times the peak demand so that pumps run intermittently instead of constantly working to fill the auxiliary tanks.

The onboard fuel pump is normally sufficient to swap fuel with the tank for applications using sub-base, or belly tanks mounted directly under the gensets. Nonetheless, for situations where the entire fuel stock can not be placed close to the gensets or where there is a fair difference in the elevation of the main or bulk storage tanks and gensets, an alternative is to use auxiliary tanks or day tanks allocated to each genset. Auxiliary tanks are tinier tanks placed at a similar elevation relatively close to the gensets. The generator engine fuel supply and return pipe are connected to the attached auxiliary tank. Fuel is moved by external pumps from the main tank to the auxiliary tanks, which have been designed to suit the system pressure specifications.

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Remote Fill Systems is the premier source for remote fill tanks and systems for generator fueling. We are committed to providing knowledgeable and experienced support to our customers from design and application through startup and commissioning. Our team has many years of experience with fuel oil as well as long experience in industrial process control and mechanical HVAC and piping systems. We have developed innovative and cost-effective products in response to customer needs, such as:


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