Valve trim

[pdp123]

Everybody knows that
Clean services require Soft Trim and Dirty services require Hardened trim.

What are the cases where clean services require Hardened trim and dirty services soft?
Please give examples.

Thanks
PME

Hard Work with Smartness is the key to success

 

[Danlap]

The question goes back again. What is Clean and Dirty?
Does anybody (who is End user) can officially claim that their Air Instrument clean? Or their industrial water is pure (not brackish at all)?

Hardened trim normally applied for a condition that the standard base material cannot handle for certain period of time. Some but not limited to:
- Brackish condition
- Amine condition
- Hot temperature
- High differential pressure
- Friction between Seat and Closure member
- prone to cavitation, water hammer, etc.
- prone to vibration
- Etc.
In general shall common (base) material prone to chipping, wear, corrosion, and other material miss-behave due to service/medium and operational condition.

The Soft trim preferred if all of above condition ALARP or mitigated. Plus if temperature lower than 150 - 200 deg Celcius (conservative industrial soft component temperature tress hold) and Chemically compatible with the product.
Kindly note that soft trim is relatively cheaper than metal and or hardened trim. But this also have effect of renewing the soft parts earlier than its metallic brother.

Regards,
MR

All valves will last for years, except the ones that were poorly manufactured; are still wrongly operated and or were wrongly selected

 

[gerhardl]

.....and size, and branch/fluid, and pressure class, and standard, and common experience, and and application, and orientation, and type of valve..............