Fuel Transfer Pumps: Diesel, Gasoline, Ethanol, Heavy Fuel Oil and Aviation

1. Industrial fuel pumps: which series for each product

Viscosity at pumping temperature is the first criterion, but not the only one. Light fuels can use centrifugal or gear pumps: the FBE 2026 catalog lists diesel, kerosene and gasoline among refinery applications. For heavy heated products such as heavy fuel oil and bunker fuel, assess FBE at a speed suited to viscosity. Reducing speed reduces flow; size, motor and suction must support the required duty point under that condition.

The decision combines viscosity, flow, pressure, suction condition (tank below the pump, underground tank, tank truck), duty (batch or continuous) and sealing requirements. The table below therefore shows the series to evaluate and the data that must come from the fuel specification or batch certificate, instead of generic typical ranges.

At FB Bombas, industrial fuel pumps come from two series manufactured in Cabreúva, São Paulo: the FBE external gear pump and the FBCN standardized centrifugal pump. The plant has CNC machining, assembly and a performance test bench conforming to ANSI/HI 14.6, the test standard for rotodynamic pumps such as the FBCN; a certified curve and FAT are included when they are part of the contracted scope.

For a quotation, provide the product, the viscosity at pumping temperature, the flow, the discharge pressure, the suction condition and the hazardous area zone.

2. Classified areas, Ex motor and safety

Fuel storage and transfer installations usually include classified areas. Classification is done by the installation design per ABNT NBR IEC 60079-10-1, in zones: Zone 0 (explosive atmosphere present continuously or for long periods, such as inside tanks), Zone 1 (likely in normal operation) and Zone 2 (not likely in normal operation and, if it occurs, only for a short period).

The zone defines the equipment protection level: per ABNT NBR IEC 60079-14, EPL Ga in Zone 0; Ga or Gb in Zone 1; Ga, Gb or Gc in Zone 2 — plus the gas group and temperature class.

In Brazil, NR-10 (item 10.9.2) requires equipment for potentially explosive atmospheres to be assessed for conformity within the Brazilian Certification System, and Inmetro Ordinance No. 115/2022 covers the compulsory certification of electrical equipment for explosive atmospheres. The motor Ex certification belongs to the motor manufacturer. State the zone, gas group and temperature class in your enquiry so that the assembly is quoted with a compatible motor and accessories.

Beyond the motor, the installation design covers grounding and equipotential bonding between pump, piping and tank (electrostatic discharge), overpressure protection on positive displacement pumps, instrumentation suited to the zone and pump-house ventilation. Among pump accessories, the FBE and FBCN manuals provide a coupling guard in carbon steel or in non-sparking material.

3. Brazilian standards applicable to fuel pump installations

A fuel transfer installation answers to technical standards (ABNT), occupational safety regulations (NRs) and the regulatory and environmental requirements of the facility. They define design and operating requirements of the installation; they are not pump certifications. FB Bombas receives these requirements in the enquiry and records the equipment scope in the proposal: motor, materials, accessories and documents.

• ABNT NBR 17505: storage of flammable and combustible liquids (tanks, distances, containment and ventilation), applied by the installation design
• ABNT NBR IEC 60079 (explosive atmospheres): Part 10-1 covers area classification and Part 14 the design, selection and erection of electrical installations
• NR-20: occupational safety and health with flammables and fuels — management, training and procedure requirements of the installation
• NR-10, item 10.9.2: equipment for potentially explosive atmospheres assessed for conformity within the Brazilian Certification System; compulsory certification of Ex electrical equipment under Inmetro Ordinance No. 115/2022
• API 610: centrifugal pump standard for the petroleum, petrochemical and natural gas industries, common in refinery and large-terminal specifications. The FBCN is not declared API 610 compliant; when the specification requires it, engineering assesses case by case
• Environmental licensing and activity regulation (competent environmental agency and ANP): facility requirements, handled by the party responsible for the installation

4. Operation types: unloading, recirculation, refueling, inter-tank transfer

Each operation has its own flow, pressure, cycle and suction condition. Instead of adopting generic typical ranges, map the real duty — operations per day, volume per operation, available time, fuel type and suction geometry — before closing the specification. The table summarizes what changes in each operation and the data that drive selection.

5. Pump sizing: flow, pressure, NPSH and relief valve

Sizing follows the methodology of any pump: design flow, total dynamic head and NPSH available. Fuel transfer adds three variables: product temperature (viscosity and vapor pressure), area classification (motor and accessories) and overpressure protection on positive displacement pumps.

A gear pump needs overpressure protection: if the discharge is blocked, pressure rises to the mechanical limit of the assembly. The FBE offers an internal relief valve as an accessory (2026 catalog, p.3).

FBEI manual MAN001-10 requires, for pumps without a relief valve, a protection system such as an in-line valve, pressure switch or torque limiter; states that the relief valve must not be used to control pressure or flow; and asks for the opening pressure to be checked at installation.

On a centrifugal pump, pressure with the discharge closed is limited by the curve, but operation at very low flow heats the liquid and increases loads. Table 1 of FBCN manual MTEC-03/00 sets minimum flow at 0.1 Qot for bearing frames 30 and 40 and at 0.15 Qot from frame 50 upwards, with a maximum of 1.1 Qot. In systems with automatic valve closure, provide minimum recirculation or an interlock.

For NPSH available, use the real product vapor pressure at the maximum operating temperature: NPSHa = absolute pressure at the liquid surface + static height − suction losses − vapor pressure, all in metres of the liquid itself. Gasoline and ethanol have a much higher vapor pressure than water, and heating oils also raises it; underground tanks and suction lift reduce NPSHa.

Use the value from the product specification or batch certificate and compare it with the NPSH required from the model curve.

6. Materials and sealing by fuel type

Chemical compatibility between the fuel and the casing, impeller, bushing and sealing materials must be confirmed for the product and temperature. The series have documented options.

The FBE lists casing in ASTM A48 CL30 cast iron, ASTM A536 ductile iron, ASTM A216 WCB carbon steel or ASTM A743 CF8M stainless, shafts and gears in SAE 1045 or 316L stainless and sealing by packing, mechanical seal or lip seal (2026 catalog); manual MTEC-01/01 also describes the magnetic coupling, a special seal-less option for applications that allow no leakage, such as corrosive, toxic or explosive fluids.

The FBCN has casings in cast iron, A216 WCB carbon steel and A743 CF8M stainless, with pressure × temperature limits in manual MTEC-03/00, and a seal chamber with application-specific executions (ST and S1 to S4) or a mechanical seal as needed.

For elastomers and seal faces, use the compatibility table of the seal or elastomer manufacturer for the real fuel — ethanol content, aromatics, biodiesel, additives and temperature. The standard FBE seal described in the manual is type 21, ceramic × graphite × Viton; another combination is specified when the fuel requires it.

7. Specific applications: stations, TRR, refineries, terminals and aviation

Each type of customer has different technical, regulatory and documentation requirements. The FBE and FBCN series are the base; motor, sealing, materials, instrumentation and documents vary with each installation specification.

• Fuel stations and TRR (retail fuel distributors): tank truck unloading and underground tanks — check NPSH available and priming; area classification defines the motor
• Distribution bases and terminals: pumps in parallel, continuous operation and integration with the site automation; the terminal specification may require design standards such as API 610, assessed case by case
• Refineries: process services usually carry the buyer own specification; the FBE 2026 catalog lists refinery applications for diesel, crude oil, greases, asphalt, kerosene, gasoline and oils in general
• Aviation (jet fuel/JET-A1): material, filtration and water-control requirements come from the fuelling-system operator specification; FB assesses the pump under that specification
• Industry with own consumption (diesel generators, oil-fired boilers and furnaces): transfer and burner feed; the FBE lists oil burners among its applications
• Port installations: heavy fuel oil (bunker) with heated FBE at reduced speed; marine diesel and light products with FBCN or FBE

8. Errors to avoid in fuel transfer projects

The errors below originate in the specification and are avoided with the right data in the enquiry:

• Selecting by fuel designation, without the viscosity at the real pumping temperature
• Specifying a centrifugal pump for heavy oil without correcting the curve for viscosity: head, flow and efficiency drop
• Installing a gear pump without overpressure protection or using the relief valve to control flow
• Installing a motor or instrument without Ex certification suited to the zone, gas group and temperature class
• Choosing elastomers without checking compatibility with the real fuel (ethanol content, aromatics, biodiesel)
• Calculating NPSH available without the vapor pressure at maximum temperature and without the real suction geometry
• Overlooking grounding and equipotential bonding between pump, piping and tank
• Not planning the pump-house ventilation and procedures required by the design and by NR-20