How to Avoid Valve Cavitation?

Control Valves
1

If cavitation in valve is ever encountered, consider the following corrective actions:

  1. The first is to equip the control valve with special trim and ensure that the plug and
    seat are made of a hard facing material that can resist both the onset and effect of
    cavitation (e.g. stellite hard facing).

  2. The second is to use a valve with a low recovery coefficient.

  3. The third is to increase the downstream pressure by installing a flow restrictor if
    possible or reducing the pipe size of a short piece downstream.

3 Likes
2

Anti Cavitation Trim:

  • Creates a bigger distance between cage and valve walls
  • This ensures flow enters the cage uniformly
  • Cavitation bubbles collapse symmetrically towards the centre of the cage

So, the trim will not make the cavitation disapear, it will handle it in the right way without destroyng the valve.

A_C_T

3 Likes
3

If I go with option #3 - how do I distribute the pressure drop? I have 350 psig drop across the control valve. I am wanting to add an RO downstream. Do I let the RO see most of this pressure drop and only take about 50 psig across the valve?

1 Like