Fisher Dirty Service Trim is designed for dirty, cavitating services.
This trim utilizes a series of flow restrictions and expansions to eliminate cavitation, while allowing up to 19 mm (3/4 in) diameter particulate to pass through without plugging. Each of the trim stages has a successively larger flow area. The result is very efficient operation because typically 80 percent of the overall pressure drop is taken in the initial stages, where there is little danger of cavity formation which could result in cavitation.
