What makes isocyanate difficult to pump
The pump is sized at the coldest working temperature and turns slowly, so the gear teeth fill completely.
The pump must not be left full and cold: it is kept warm, kept full or flushed at every stop.
Tight sealing and a closed system are part of the specification.
How we build the pump for isocyanate
| Recommended series | ZV · NAV |
|---|---|
| Flow range of these series | 0.47 – 2,770 l/min (0.03 – 166 m³/h) |
| Body material | Cast iron as standard; stainless steel NAV for aggressive variants |
| Heating | Recommended in cold climates, for long storage or where the product thickens at night |
| Speed | Low speed: a larger pump turning slowly, often with a gear motor or inverter |
| Shaft seals | Kept wet or flushed at shutdown to avoid deposits on the faces |
| Connections | NAV: flanged DN 40 – DN 125 PN 16; ZV: threaded ports, close-coupled to the motor |
Where isocyanate pumps work
Applications: PU foam machines, panel lines, coatings and adhesives, elastomers.
Typical markets: Turkey, Egypt, Saudi Arabia, Iran, India, Vietnam, Indonesia, Mexico, Brazil. For these sites we size for local conditions: the coldest night temperature, 50 or 60 Hz power, heating available on site and spare parts that can be kept in stock locally.
Recommended pump series
Data we need to size your isocyanate pump
- Product name, producer or data sheet of the isocyanate
- Viscosity at the pumping temperature, and the lowest temperature on site
- Flow rate required (l/min, m³/h or bbl/h)
- Discharge pressure, or line length, diameter and height
- Suction: tank, line length and diameter, liquid level
- How often the line stops, and for how long
- Power supply: voltage and 50 or 60 Hz
Frequently asked questions
Which gear pump do you recommend for isocyanate?
We normally propose the ZV or NAV Series. The ZV is compact, for small flows and dosing, close-coupled to the motor. The final model depends on flow, viscosity at temperature and suction, and is confirmed by our technical office.
Why do you size the pump for isocyanate larger than the flow requires?
Because a viscous fluid needs time to fill the gear teeth. A larger pump turning slowly fills completely, runs quietly and wears far less than a small pump at high speed.
Do you supply pumps outside Italy?
Yes. The pumps are built in our Bologna workshop and quoted for export. Write your country in the form and we will size the pump for your power supply (50 or 60 Hz) and site conditions.
This page also covers: MDI, TDI, Isocyanate and polyol, Isocyanate and resins.