What the NAV series is designed for
The NAV is the general-purpose industrial pump of our range: a self-priming external gear pump for fluids that go from thin oils to products of very high viscosity, with high volumetric efficiency, minimal internal slip and a constant flow without pulsation. It delivers high discharge pressure together with high flow, which is why it runs 24/7 in petrochemical plants.
Typical fluids are fuel and thermal oils, heavy lubricants, petrol and diesel, solvents, high-density resins, isocyanates, paints, soaps, pitch and molten polymers; chocolate and molasses in the food version. As standard the NAV is supplied without heating jacket; for products that solidify at room temperature we recommend the jacketed CR series, which shares the same principle.
NAV series models and flow rates
Nine sizes from 1 NAV to 5 NAV, with displacements from 120 to 1,910 cm³/rev. The table gives the flow in l/min at three reference speeds for the smallest and the largest model; the seven intermediate models cover the band between them in regular steps.
| Model | Displacement cm³/rev | 450 rpm | 950 rpm | 1,450 rpm |
|---|---|---|---|---|
| 1 NAV | 120 | 54 | 114 | 174 |
| 1 1/2 NAV | intermediate size, between 120 and 1,910 cm³/rev | |||
| 2 NAV A | intermediate size, between 120 and 1,910 cm³/rev | |||
| 2 NAV B | intermediate size, between 120 and 1,910 cm³/rev | |||
| 2 1/2 NAV | intermediate size, between 120 and 1,910 cm³/rev | |||
| 3 NAV | intermediate size, between 120 and 1,910 cm³/rev | |||
| 3 1/2 NAV | intermediate size, between 120 and 1,910 cm³/rev | |||
| 4 NAV | intermediate size, between 120 and 1,910 cm³/rev | |||
| 5 NAV | 1,910 | 859 | 1,814 | 2,770 |
Ask us for the data sheet of the intermediate models: we select the size on your flow, pressure and viscosity rather than on the nearest catalogue value.
Construction: flanges, base, materials
- Flanged ports UNI from DN 40 to DN 125 PN 16, so the pump drops into existing pipework without adapters.
- Self-priming, constant flow, with high discharge pressure together with high flow and minimal internal slip.
- Cast iron base for pump and motor, with coupling and guard.
- Stainless steel versions for aggressive fluids, acids, caustic soda, solvents and isocyanates.
- Food version for chocolate and molasses, where cast iron is acceptable but surface finish and seals are adapted to the product.
- No heating jacket as standard; electric cartridge heating can be fitted where the product needs to be kept warm without a thermal plant.
ATEX documentation is available for installation in classified areas. Quality is certified ISO 9001:2015 and every component is machined in our Bologna factory.
Applications of the NAV high-viscosity pumps
- Transfer of heavy fuel oil, bunker fuel, diesel and lubricants in refineries, depots and boiler rooms, with continuous duty.
- Circulation of thermal oil in plant-wide heating loops.
- Transfer of high-density resins, isocyanates and paints in chemical and coating plants, in stainless steel where required.
- Handling of bitumen emulsion in emulsion plants and loading bays.
- Transfer of molasses and chocolate in sugar, feed and confectionery plants, in the food version.
- Pitch, molten polymers, soaps, glycerine, landfill leachate and other viscous fluids where a flanged pump with high pressure and high flow is needed.
Where small flows or precise dosing are required, the ZV series takes over from the NAV.
How to request a NAV pump
To select the right NAV model we need the fluid and its viscosity at the working temperature, the temperature range, the flow in l/min or m³/h, the discharge pressure, the suction conditions (tank level, length and diameter of the suction line), the presence of solids and the drive you prefer. Tell us whether a stainless steel or food execution is required and whether the installation is in an ATEX zone.
Write on WhatsApp or fill in the quote form. Our Bologna factory, building self-priming external gear pumps since 1955, replies with the model, the speed, the motor power and the material that fit your duty, usually within one working day.
Frequently asked questions
What flow rates does the NAV series cover?
From 54 l/min with the 1 NAV at 450 rpm to 2,770 l/min with the 5 NAV at 1,450 rpm. The seven intermediate models cover the displacement band between 120 and 1,910 cm³/rev.
Are NAV high-viscosity gear pumps suitable for continuous duty?
Yes. The NAV series is designed for 24/7 operation in petrochemical plants, with high volumetric efficiency, minimal internal slip and a constant flow without pulsation, even at high discharge pressure.
What connections do NAV pumps have?
Flanged ports UNI from DN 40 to DN 125 PN 16, mounted on a cast iron base with the motor. This makes the pump a direct replacement in existing flanged pipework.
Does the NAV series have a heating jacket?
Not as standard. For fluids that solidify at room temperature we recommend the CR series with full heating jacket; the NAV can be fitted with electric cartridge heating where the product only needs to be kept warm.
Is a stainless steel NAV available?
Yes. Stainless steel versions are built for aggressive fluids such as acids, caustic soda, solvents and isocyanates, and a food version is available for chocolate and molasses.