Suntec E7NC-1069-7P Heavy Oil Gear Pump

Suntec E-Series Gear Oil Pump: Model E7NC-1069-7P

The Suntec E7NC-1069-7P is an industrial-grade, heavy-duty positive displacement gear pump engineered specifically for medium and heavy fuel oil (HFO) combustion systems, marine auxiliary boilers, thermal fluid heaters, and heavy-duty industrial burners. Featuring integrated thermal management channels and a specialized high-temperature fluoroelastomer/viton mechanical shaft seal, the E 1069 series operates reliably with heated viscous media up to 130°C.

The pump incorporates an integrated pressure-regulating spool without an internal positive hydraulic cut-off. Instead, a specialized nozzle bypass port bleeds trapped expansion pressure back to the return line during shut-down, protecting fuel preheaters and burner assemblies from thermal hydraulic shock.

Key Performance Features

1. Thermal-Shock Resistant Viton Lip Seal: Engineered to withstand thermal expansion and prevent shaft leakage under sustained high-temperature HFO operation up to 130°C.
2. Dual-Side Electric Preheater Cavity: Houses a standard Ø 12 mm / 80–100 W heating cartridge insertable from either the left or right flank to liquefy cold, high-viscosity residues prior to cold start.
3. High-Throughput Gear Mechanism: Delivers steady, pulse-free fuel delivery up to 375 L/h across a pressure band of 14 to 30 bar.
4. Thermal Expansion Relief System: Built-in nozzle bypass bleed prevents destructive hydraulic overpressurization caused by downstream line heater thermal expansion.
5. Field-Convertible Piping Setup: Simple 3/16″ Allen-key removal of the internal bypass plug converts the unit from a 2-pipe recirculating circuit to a 1-pipe system with suction return.

Applications

• Marine Auxiliary & Exhaust Boilers: Aalborg, KangRim, Miura, and Saacke marine auxiliary boiler fuel firing loops.
• Thermal Fluid Heaters: Industrial hot-oil circulating systems (HTF) and marine cargo heating units.
• Heavy Industrial Burners: Rotary cup and pressure-jet burners firing Marine Gas Oil (MGO), Marine Diesel Oil (MDO), Intermediate Fuel Oil (IFO 180 / 380), and Heavy Fuel Oil (HFO).
• Asphalt & Bitumen Plants: Direct-fired rotary dryers and mixing plants requiring heated heavy oil transfer.
• Power Generation & Incinerators: Marine waste oil / sludge incinerators and auxiliary gen-set boiler firing units.

Burner & Boiler OEM Compatibility

• Weishaupt: Monarch Heavy Oil Series (RMS, RMS7, RMS8, RMS9, RMS10, RMS11).
• Riello: Heavy Oil & Dual Fuel Series (PRESS G, PRESS T/G, MB 4N, MB 6N, MB 8N).
• Saacke: Rotary cup and steam/air atomized burner fuel modules.
• Oilon: Heavy oil burners (KP-80 H, KP-90 H, KP-140 H series).
• Baltur / Elco / Dunphy: Multi-fuel industrial series burner assemblies.

Preheating Strategy & Cold-Start Prevention

Marine Chief Engineer’s Note: Heavy Fuel Oil (HFO) solidifies at ambient temperatures. Never attempt to start the burner motor while the fuel inside the pump body is cold. This will shear the drive coupling or destroy the internal gear splines.

• Energize the pump’s Ø 12 mm heating cartridge at least 20–30 minutes before system commissioning.
• Verify that the viscosity of the fuel entering the pump suction port is brought down to below 75 cSt (ideally between 15–25 cSt at the nozzle manifold).

Frequently Asked Questions

What does the “C” rotation designation mean on the E7NC-1069-7P?

“C” designates anti-clockwise shaft rotation when looking directly face-on at the pump drive shaft, with the nozzle outlet port located on the left-hand side of the pump housing.

Can the Suntec E7NC-1069-7P run on Low-Sulfur Marine Gas Oil (MGO)?

Yes. While optimized for heavy fuel, it can handle distillate and low-sulfur fuels down to 3 cSt (and down to 2.8 cSt / 1.2°E for short durations). For prolonged ultra-low-sulfur MGO operations, ensure fuel lubricity additives or maintain adequate fuel cooling to prevent hydrodynamic boundary lubrication failure.

Why is an external solenoid valve required with this pump?

The E 1069 series features an internal bypass drilling inside the nozzle plug designed to release excess hydraulic pressure caused by fuel expansion inside nozzle preheaters during shutdown. This design deliberate eliminates internal tight cut-off, making a downstream inline solenoid valve mandatory for safety cut-off.

How do I convert the pump from a 2-pipe system to a 1-pipe system?

To convert to a 1-pipe system, remove the return port connection fitting, use a 3/16″ Allen hex key to unscrew and remove the internal by-pass plug inside the return line, and install a pressure-tight steel plug with a copper sealing washer into the G 1/2″ return port.

What is the direct replacement if model E7NC-1069-7P is obsolete?

The direct manufacturer-engineered drop-in replacement is the Suntec E7NCK-1069-8P (part number 112000164), which retains identical mounting flange dimensions, shaft specifications, rotational orientation, and port thread alignments.