Unlike cavitation, the bubbles never collapse: the outlet becomes a high-velocity mix of vapor and liquid droplets that erodes trim and the downstream body with smooth, polished, scalloped wear. Flashing cannot be designed out by trim, because it is set by the process pressures, so the answer is hard trim, angle bodies discharging into a larger pipe, and outlets sized for the vapor volume.
Hot condensate letdown is flashing through the valve, plan on a hardened plug and an angle body this time.
Also heard as
- flash
Related terms
Cavitation
Vapor bubbles forming and then collapsing in a liquid passing through a valve, causing noise, vibration and pitting.
Trim
The replaceable internal parts of a valve that touch the process fluid, such as seat, disc or plug, stem and cage.
Control valve
A power-operated valve that modulates flow on a controller signal to hold pressure, level, flow or temperature at setpoint.