The unique Grundfos air-cooled top shaft seal solution is recommended for application involving high temperatures from 248 °F to 356 °F. The air-cooled top separates the seal chamber from the pump by an air-cooled chamber, generating an insulating effect similar to that of a thermos. Via the narrow passage between the pump and the air-cooled top, a small quantity of the pumped liquid recirculates by natural circulation. Temperatures above 248 °F normally result in a substantial reduction of seal life dude to poor lubrication of the seal faces. As the temperature in the seal chamber does not exceed 248 °F during operation, a standard Grundfos shaft seal can be used. The Grundfos air cooled-top does not require any external cooling. An automatic air vent is required to vent the pump seal chamber.
- Boiler feed
- Temperature control
- Circulation of transmission oils