Clean fluid is injected into the seal chamber from an external source.
Satisfactory plan for use in achieving a clean and cool environment. Requires the injection of clean fluid from an external source.
- For use in services containing solids or contaminants, in which a cleaner and cooler external flush will improve the seal environment.
- External flush source must be continuous and reliable.
- Pressure of the external flush should always be at least 25 psi [1.7 bar] above the seal chamber pressure.
- Throat bushing is required to maintain an elevated pressure in the seal chamber, isolate it from the pumped media, and reduce flush fluid consumption.
- Provides the seal with a cool, clean lubricating fluid when the product cannot be conditioned into a quality seal flush through the use of other piping plans.
- Flush fluid must be compatible with the product because product dilution will occur.
- Improved cooling, lubricity and cleanliness of process fluids
- Higher energy requirements