DIAPHRAGM PUMP HIGH VISCOSITY APPLICATIONS
As you can see from the diagram, as viscosities increase, the capacity of the pump decreases. Do not exceed 22,000 centapoise or 100,000 saybolt seconds on all 3/8˝ up to 3˝ pumps. Do not exceed 4,000 centapoise or 18,000 saybolt seconds on 1/4˝ models.
Some points to remember when pumping high viscosities:
- Position the pump close to or below the level of the fluid source.
- Suction lines should be increased in size—up to three times the size of the pump manifold inlet. Dual manifolds may be used when available.
- Start the pump slowly using a control valve on the air line.
- Maximum air pressure required is reached when increasing the air pressure does not increase the flow rate.
- If greater capacity is required, select a larger pump.