What is a Condensate Slug in Steam Lines ?

A Condensate slug occurs when condensate which collects in a steam line and moves through it at high speed encounters a point of resistance such as a bend or a closed valve. 

The condensate travels at the speed of the steam in the line.  When this condensate meets a point of resistance such as a bend in the pipeline or a pressure reducing valve, a tremendous impact occurs.  The shock wave travels through the system getting reflected many times.  This results in hammering.  This can cause damage to the pipelines and even injury or death to personnel.

Hence, adequate precautions to prevent such a scenario. 

Steam Traps should be fitted at points where the line makes sharp turns.  Steam Traps should also be placed before pressure reducing valves and valves which are mostly closed and at the end of steam lines.