The FBEI Series is FB Bombas' internal gear pump line — manufactured in Cabreúva-SP since 1944 per API 676, with 10 catalogued models (technical manual MAN001-10) covering sizes from 1" to 4" in three construction configurations (with integrated relief valve, compact and heavy-duty 3"). Operating principle "gear within a gear" with rotor + idler + crescent, ideal for viscous fluids with low pulsation. Sealing by mechanical seal or braided packing, optional heating jacket (steam up to 185°C / thermal fluid up to 232°C, both at 10 bar). FBEI-LS engineered-to-order version for large capacities in asphalt, bitumen and heavy oils. CRCC Petrobras qualified supplier — Family 6 (Rotating Equipment).
FB BOMBAS
SeriesFBEI
Internal gear technology for gentle transport of viscous fluids. Quiet operation, low pulsation, and continuous flow — ideal for demanding industrial applications.
Internal Gear Pumps
Technical ManualDiscover the FBEI Series
Internal gear pump for viscous fluids
The FBEI series uses the "gear within a gear" principle to transport viscous fluids with continuous flow and very low pulsation. Available with mechanical seal or packing, optional heating jacket, and integrated relief valve. Models from 1" to 4" with multiple casing configurations.
Mechanical seal or packing per application
Integrated relief valve for overpressure protection
Optional heating jacket (steam up to 185°C / thermal fluid up to 232°C)
Models from 1" to 4" — multiple casing configurations
More Angles
Perspective View
Dual Assembly
Operating Principle
Positive displacement pumping cycle with internal gear and crescent separator
Cutaway View
Pumping Cycle
01
Suction
The rotor (internal gear) is driven by the shaft and meshes with the idler (external ring gear). In the disengagement zone, the volume between the gears progressively expands, creating a partial vacuum that draws fluid through the suction port.
02
Crescent Isolation
The fixed crescent-shaped separator — the crescent — fits between the rotor and idler, hermetically isolating the suction chamber from the discharge chamber. This prevents backflow and ensures flow directionality.
03
Volumetric Transfer
Fluid trapped between the gear teeth and the crescent surface is carried from suction to discharge by positive displacement. The volume delivered per revolution is constant and independent of system pressure.
04
Discharge
In the re-engagement zone, the rotor teeth re-mesh with the idler ring, progressively reducing the chamber volume and forcing fluid out through the discharge port — with minimal pulsation and no significant product shear.
Type
Positive displacement
Separator element
Crescent (fixed)
Self-priming
Yes — no foot valve needed
Pulsation
Minimal — near-laminar flow
Shear
Very low
Reversible
Yes — bidirectional
Internal Gear Advantages
Why choose internal gear technology
Quiet Operation
Low noise and vibration operation, ideal for industrial environments with noise restrictions.
Low Pulsation
Continuous, uniform flow without pressure spikes. No pulsation dampeners needed.
Wide Viscosity Range
Operates efficiently from light fluids to extremely high viscosity products. Available with heating jacket for fluids requiring temperature control.
Self-Priming
Self-priming capability that simplifies installation and eliminates need for auxiliary devices.
Integrated Relief Valve
Built-in overpressure protection. Ensures operational safety without the need for external devices in the line.
Easy Maintenance
Few moving parts and simplified design. Available with mechanical seal or packing, depending on the application, allowing quick maintenance and low operating cost.
FBEI-LS — Heavy-Duty with Gearbox
Robust version of the internal gear for heavy industrial applications
FBEI-LS
Heavy-duty internal gear with speed reducer
Cast iron or steel body, large-dimension internal gears and speed reducer drive — the FBEI-LS is engineered to order for large-scale viscous fluid transfer: asphalt, bitumen, heavy oils and petroleum derivatives.
Speed reducer drive system
Large-dimension internal gears
Structural base with lifting lugs
Engineered to order per application
Other Views
Full Assembly
Isometric View
High Capacity
Designed for large volume movement in loading, unloading, and heavy industrial transfer operations.
High Temperature
Operates with high-temperature fluids. Ideal for asphalt, heated bitumen, and thermal oils in demanding industrial processes.
Ultra-High Viscosity
Capable of pumping ultra-high viscosity fluids. The reducer ensures sufficient torque for extremely dense and heavy products.
From Blueprint to Reality
Every application requires a unique specification
Every FBEI pump starts as an engineering project — gear geometry, casing and shaft validated in 3D CAD. CFD simulations confirm hydraulic performance under the customer's real operating conditions.
Our engineers analyze your fluid, temperature and process to size the ideal pump. Request a no-obligation technical consultation.
Sectors & Applications
Solutions for viscous fluids across various industrial segments
Petrochemical
Oils and petroleum derivatives
Chemical
Resins, solvents and polymers
Food Industry
Chocolate, molasses and vegetable oils
Pharmaceutical
Emulsions, creams and viscous bases
Paints & Coatings
Paints, varnishes and pigments
Asphalt
Bitumen and asphalt emulsions
Adhesives
Hot-melt adhesives and sealants
Oils & Lubricants
Lubricants and hydraulic oils
and many other sectors...
Available Models
10 FBEI models — select by construction configuration
Compact
2 models
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With Relief Valve
5 models
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Heavy-duty 3"
3 models
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Engineering & Manufacturing
Technical capability for custom projects
CFD Simulation
Computational fluid analysis for hydraulic optimization before manufacturing
CNC Machining
High-precision machining center for finishing critical components
Custom Design
Dedicated engineering for sizing according to your specific application
Quality Control
Hydrostatic and performance testing on our own test bench
Companies that Trust FB Bombas
Present in the largest industrial projects in Brazil and Latin America
Need an internal gear pump?
Send us your fluid data and operating conditions. Our engineering team will size the ideal FBEI pump for your application.
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