Emerson Exchange 365

I wanted to share a ControlGlobal.com blog post from Greg McMillan that I saw in the DeltaV track, Checklist for Best Control Valve Performance. His list of questions includes:

1. Does sizing software have the fluid physical properties for worse case operating conditions?
2. Does location and valve type eliminate or reduce damage from flashing and erosion?
3. Did you include swage effect from piping reducer?
4. Did you compute and plot installed valve characteristic for worse case operating conditions?
5. Is actuator sized to deliver twice the max torque or thrust required?
6. Is actuator threshold sensitivity better than 0.1%?
7. Is positioner threshold sensitivity better than 0.1%?
8. Is smart positioner tuned for application (otherwise you have a dumb positioner)?
9. Is total valve assembly deadband less than 0.4% over the entire throttle range?
10. Is total valve assembly resolution better than 0.2% over the entire throttle range?
11. Is installed characteristic slope > 0.5% max flow per % signal over the entire throttle range?
12. Is installed characteristic slope < 2.0% max flow per % signal over the entire throttle range?