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Model FBEI

FBEIM4

Internal gear pump — nominal size 4" — with integrated relief valve.

Nominal Size: 4"272 kgDownload FBEI Technical Manual
Model
FBEI M4
Nominal Size
4"
Approximate Weight
272 kg
Manual Reference
Fig. 8
Configuration: With integrated relief valve

Technical Dimensions

Dimensions in millimeters per FBEI Technical Manual — FB Bombas

DimensionValue (mm)
A4"
B241,0
C438,0
D254,0
E127,0
F152,0
G305,0
H216,0
J18,0
K102,0
L197,0
M206,0
N102
O25
P38
R511
S721
T108
U49,21
W216

Source: Official FBEI Technical Manual (Fig. 8) — all dimensions in millimeters. Missing fields do not apply to this configuration.

Construction Features

Per official manufacturer documentation

Operating Principle

Positive displacement — gear within a gear (rotor + idler + crescent)

Sealing Options

  • Mechanical seal (single or cartridge)
  • Braided packing with adjustable gland

Relief Valve

Integrated relief valve with adjustable setting — overpressure protection. Adjustment screw cap oriented toward the suction side.

Heating Jacket (optional)

Steam must not exceed 185°C and/or 10 bar. Thermal fluid limited to 232°C and/or 10 bar (technical manual).

Installation Requirements

Suction filter40–80 mesh
Alignment toleranceradial < 0.05mm · angular < 0.6°
Pre-alignmentYes — performed at factory
Self-primingYes — no foot valve required
ReversibleYes — reversible by rotation direction

Spare Parts (2 years)

  • Internal gear
  • Pin
  • Support and internal gear bushings
  • Sealing kit (packing or mechanical seal + bearing)
FB Engineer·Technical perspective on this configuration

When to choose the with-relief-valve configuration

This configuration is the standard choice for industrial applications where the discharge line may become blocked or closed during operation. The integrated relief valve protects the pump from overpressure without needing an external device in the line — simplifies hydraulic design. Indicated for continuous transfer of viscous fluids in processes where operational safety is critical.

Frequently Asked Questions

Model-specific technical answers based on the official manual

The FBEI M4 pump has a nominal size of 4" on both suction and discharge, according to the official dimensional table in the FBEI Technical Manual (Fig. 8).
The approximate weight of the FBEI M4 pump is 272 kg (hydraulic assembly only, excluding motor, coupling and base), per the FBEI Technical Manual. For the total assembly weight including motor and base, contact FB Bombas engineering.
Yes. All pumps in the FBEI series, including the M4 model, are self-priming — no foot valve required at the suction point. The technical manual recommends installation as close as possible to the suction source, with a 40-80 mesh filter to prevent cavitation.
Yes. The positive displacement principle (internal gear + crescent) allows bidirectional operation. Simply reverse the motor rotation direction to reverse suction and discharge flow.
The FBEI M4 can be supplied with mechanical seal (single or cartridge) or braided packing with adjustable gland. The choice depends on the fluid and operating conditions — consult FB Bombas engineering for technical recommendation.
Yes. The FBEI M4 can be supplied with an optional heating jacket for viscous fluids requiring pre-heating. The technical manual defines operating limits: steam up to 185°C and 10 bar, or thermal fluid up to 232°C and 10 bar. The jacket must be heated gradually to prevent thermal shock.
Yes. In the "with integrated relief valve" configuration, the FBEI M4 has an integrated relief valve for overpressure protection. The manual specifies that the adjustment screw cap must face the suction side and the opening pressure must be pre-regulated.
The FBEI Technical Manual recommends a 40 to 80 mesh filter (depending on model and application) with passage area equal to or greater than the pump suction nozzle — prevents solid particle ingress and extends internal gear service life.
Radial alignment tolerance is under 0.05 mm and angular tolerance is under 0.6°. FBEI pumps leave the factory pre-aligned, but transport and handling can disturb alignment — re-alignment is mandatory after installation on the final base.
Per Section 3 of the FBEI Technical Manual, recommended parts for 2-year operation are: internal gear, pin, support and internal gear bushings, and sealing kit (packing or mechanical seal + bearing). 4" sizes (M4) are for large-scale industrial applications — massive viscous fluid transfer, typical in terminals, refineries and large process installations.

Application-Specific Performance

Flow rate, pressure, speed and power are sized for each specific application (fluid, viscosity, temperature, required pressure and available NPSH). Request free technical sizing — response within 48 business hours.

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All dimensions and construction information were extracted from the official FB Bombas FBEI Technical Manual. For customized performance specifications, consult the Technical Assistance Department.