Cascade and Super Cascade
Description
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. Featuring a series of labyrinth grooves machined into the plug’s throttling surface, the trim creates a cascading effect that divides the pressure drop equally among the grooves. This reduces inner valve pressure recovery and vapor formation. Cascade trim is ideally suited for applications where cavitation can exist at low flow conditions, such as when the plug is just off the seat, by maintaining a controlled clearance between the plug and the cage.
Features
- Cage guiding, a Copes-Vulcan standard, includes a 30° seating angle on the plug and 32° in the cage seat.
- Seat contact width is approximately 0.025” (0.635 mm).
- Valve actuator is selected to ensure exceptionally tight seating under operating conditions.
- High seating force causes slight deformation of seating surfaces, resulting in tight shutoff.
- Cage and plug are made from ASTM A-276 Type 420 stainless steel with Rockwell C-43 to C-47 hardness.
- Optional materials include ASTM A-351 Type 316 stainless steel with hardfacing and 17-4PH stainless steel.
- Materials offer high resistance to erosion and are proven suitable for severe service conditions.
- Tolerance-controlled machining and strict quality control ensure consistency with Copes-Vulcan specifications.
- Cascade Trim has been extensively tested and proven in demanding high-pressure, high-temperature applications.
Applications
- Desuperheater cooling water control
- Reheat and superheat spray control
- Fuel oil control valve
- Steam PRV
- Soot blower thermal drain
