DMN BL200 - Inspection and Maintenance Procedures

DMN-WESTINGHOUSE Explosion-Proof Rotary Valves
Code: RV-Ex.pro-E.B.01.D 05-2016
20
5. Inspection and Maintenance
The interval between overhauls will vary according to the product being handled and
should be based on total operating time. To a large degree the rate of wear for a
particular application will be ascertained by practical experience.
It is recommended that the complete rotary valve is dismantled for cleaning,
inspection and overhaul as necessary at regular intervals.
The plant operator must ensure that any possible dust
accumulation does not exceed a maximum thickness of 5 mm in
accordance with EN50281-1-2.
5.1. Checking rotor clearances
When the Rotary valves are used in abrasive applications,
regularly check the clearances between rotor and Body/Cover.
 Check clearances using the following Table.
Type
Size
Dust class
Max. Cleareance
AL
150-175-200-250-300-350
St.1
 0.2mm
AML
150-200-250-300-350
BL
150-175-200-250-300-350
AL
400-450-500
 0.3mm
AL
150
St. 2
< 0.15mm
ML
150
St1.
 0.2mm
MLD
150
The rotary valve is no longer a protective system when the rotor
clearances are higher then mentioned in the table.
Check rotor clearances:
- Before installing the valve in the system.
- At regular intervals.
The interval between overhauls will vary according to the product being
handled.