What makes sodium silicate difficult to pump
The pump is sized at the coldest working temperature and turns slowly, so the gear teeth fill completely.
Body, gears and seals are selected for the chemistry, concentration and temperature, and confirmed by our technical office.
The pump must not be left full and cold: it is kept warm, kept full or flushed at every stop.
How we build the pump for sodium silicate
| Recommended series | NAV · ZV |
|---|---|
| Flow range of these series | 0.47 – 2,770 l/min (0.03 – 166 m³/h) |
| Body material | Stainless steel or a material confirmed for the concentration and temperature |
| 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 |
The real enemy is drying, not viscosity
Most sodium silicate pump failures happen after a weekend: the product dries on the shaft and on the seal faces, and on Monday the seal tears. We plan a water flush on shutdown and keep the seal area wet; viscosity, by comparison, is the easy part for a gear pump.
Where sodium silicate pumps work
Applications: Detergent plants, foundry binders, cement and soil stabilisation, paper and cardboard, water treatment, silica production.
Typical markets: Egypt, Saudi Arabia, Turkey, India, Pakistan, Indonesia, Vietnam, Nigeria, 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 sodium silicate pump
- Product name, producer or data sheet of the sodium silicate
- 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
- Concentration and temperature of the product
- 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 sodium silicate?
We normally propose the NAV or ZV Series. The NAV is flanged from DN 40 to DN 125, for transfer and plant duty. 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 sodium silicate 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: Water glass.