Unidirectional Flushing (UDF)
Definition - What does Unidirectional Flushing (UDF) mean?
Unidirectional flushing (UDF) is a hydraulic cleaning method used to clear blockages, debris and other unwanted material from pipe mains. This technique involves deliberately directing high-pressure, high-velocity water flow in a single direction through a single pipeline. UDF is used by utility companies to reduce turbidity and enhance chlorine residual; thus improving overall water quality.
Corrosionpedia explains Unidirectional Flushing (UDF)
During unidirectional flushing (UDF), water flow in the pipeline distribution network is isolated and directed to the target pipeline by closing specific valves. Once valve closure is complete, the hydrant at the relevant location is opened, allowing high-velocity water to exit the system, effectively flushing the target pipeline.
UDF's enhanced cleaning efficiency over other flushing methods is due mainly to its forceful concentration of high-velocity water through the pipeline under consideration. Conventional flushing, on the other hand, is not directed toward a single pipe; instead, multiple pipes are flushed simultaneously, allowing flows to come to the hydrant from random directions.
The efficiency of UDF makes it an ideal technique for cleaning hard-to-remove material such as tuberculation from metal piping.