Fuji Techno 204AVFf-SF-VB Gear Pump with Nidec FELQ-8T Motor

Fuji Techno 204AVFf-SF-VB Internal Gear Pump with Nidec FELQ-8T Induction Motor

The Fuji Techno 204AVFf-SF-VB is a positive displacement internal gear pump coupled with a heavy-duty Nidec FELQ-8T totally enclosed fan-cooled (TEFC) 3-phase induction motor. Engineered for handling light distillate fuels, heavy fuel oils (HFO), low-sulfur marine gas oils (LSMGO), and lubrication oils, this skid-mounted assembly provides pulseless fluid displacement across variable viscosity ranges.

Equipped with an integrated adjustable safety relief valve (VB designation) and a flanged mechanical seal casing (SF designation), this assembly is specifically configured to withstand the mechanical vibration, ambient thermal stress, and continuous duty cycles typical of commercial marine engine rooms and land-based power plants.

Model Details:

• Pump Model: 204AVFf-SF-VB
• Coupled Motor Model: Nidec FELQ-8T
• Pump MPN: FT-204AVFf-SF-VB-01
• Motor MPN / Frame: FELQ-8T-0.75-4P / IEC 80M
• Complete Assembly Part Code: FT-204AVF-FELQ8T-SET

Technical Specifications

Key Features

1. Constant Displacement with Low Shear: Precision-machined crescent and internal gear geometry guarantees laminar, pulseless flow without fluid cavitation or emulsification across viscosities up to 1,500 cSt.
2. Dual-Direction Integral Relief Valve: The pre-installed “VB” bypass valve protects upstream pipework and the motor winding from overpressure scenarios caused by cold starts or closed downstream valves.
3. Severe-Duty TEFC Drive: The Nidec FELQ-8T motor features vacuum pressure impregnated (VPI) Class F insulation rated for Class B temperature rise, ensuring thermal reserve in engine control spaces up to 50°C ambient.
4. Cartridge Mechanical Face Seal: High-grade Viton/FKM secondary elastomers combined with self-aligning rotary faces prevent external leakage under continuous suction heads up to 0.2 MPa.
5. Close-Coupled Rigid Alignment: Precision-machined bell housing aligns pump shaft runout within 0.03 mm TIR directly to the motor pinion shaft, eliminating flexible coupling wear and radial vibration.

Compatibility:

• Marine Diesel Main Engines: MAN Energy Solutions B&W S35ME/MC, S40ME-C; WinGD X35, X40 fuel conditioning systems.
• Marine Auxiliary Engines: Yanmar 6EY18AL, 6N21AL; Daihatsu 6DK-20e, 5DC-17 fuel supply and injector cooling circuits.
• Boiler Combustion Systems: Aalborg / Miura / KangRim auxiliary boiler HFO service burner feeds.
• Separators & Purifiers: Alfa Laval Pure-Fuel modules, Mitsubishi Self-Cleaner (SJ series) feed circulation.

Cross-Reference Part Numbers

• Fuji Techno: 204AV-SF, 204AVF-VB, 204A-01
• Nidec / US Motors: FELQ-8T-4P-0.75, 80M-4-075
• Equivalent Third-Party Units:
  • Taiko Kikai: HNP-201 / NHG-0.5
  • Tsurumi: KGP-200A
  • IMO Pump: ACD 025L4 NVBP (Interchangeable duty envelope via pipe adaptors)

Applications

• Marine Fuel Oil Booster Modules: Supplying heavy fuel oil (HFO) or LSMGO to marine main engines and generators under controlled head pressures.
• Diesel Injector Nozzle Cooling: Recirculating treated cooling oil through diesel cylinder head injector sleeves.
• Auxiliary Gearbox Lubrication: Continuous-pressure lubrication of marine reduction gearboxes, PTO shafts, and thrust bearings.
• Industrial Burner Feeds: Pumping heavy residual fuel to commercial kilns, power-plant boilers, and incinerators.
• Thermal Oil & Hydraulic Circulation: Transferring hydraulic fluid and heavy lubricating stocks in industrial factory settings.

Frequently Asked Questions

Can this pump handle Low-Sulfur Marine Gas Oil (LSMGO)?

Yes. However, LSMGO has low lubricity and low viscosity (down to 1.5–2.0 cSt at high temperatures). When pumping light distillates, keep discharge pressure below 0.6 MPa and verify operating fluid temperatures do not exceed 45°C to avoid internal slippage and boundary-friction wear between the crescent and the idler.

What is the exact replacement interval for the mechanical seal assembly?

Under continuous duty (24/7 auxiliary engine service), inspect the mechanical seal tell-tale drain port every 4,000 running hours. Plan full mechanical seal cartridge replacement between 8,000 and 12,000 running hours, or immediately if leakage through the drain passage exceeds 5 drops per minute.

What causes the internal bypass valve to squeal or chatter?

Chatter typically indicates that the downstream line is throttled too tightly, forcing the pump’s integrated relief valve to bypass fluid continuously back into the suction chamber. Alternatively, it can indicate that the internal spring has lost tension from thermal fatigue. Readjust the internal spring tension via the end-cap adjustment screw or install a dedicated return-to-tank bypass line.

How do I reverse the flow direction on the 204AVFf pump?

The 204AVFf-SF-VB pump casing is direction-dependent because of the internal geometry of the crescent and the fluid paths of the integrated VB bypass valve. Reversing the 3-phase motor wiring will invert flow, but will render the integrated relief valve inoperative and starve the mechanical seal of proper lubrication. For opposite suction/discharge arrangements, contact engineering to configure an inverted casing setup before installation.