Copes-Vulcan Cascade trim solves the problems of short life and high replacement costs for valve trim in high-pressure drop service. It is a cage-guided plug throttling trim designed primarily for high-pressure drop water applications where cavitation, vibration and excess wear would occur with conventional trims.
Cascade trim features a series of labyrinth grooves, machined into the plug along its throttling surface. This series of grooves provides a cascading effect, so that the pressure drop is divided equally among the grooves. This reduces the amount of inner valve pressure recovery and subsequent vapor formation. Cascade trim is ideally suited for applications where cavitation can exist at low flow conditions, when the plug is just off the seat. By holding the clearance between the plug and the cage in the labyrinth groove section to close tolerances, the proper cascading effect is achieved.