RL Rotary Valve
Executive summary
Process buildup throughout the rotary valve assembly prevented vane tip-to-housing gap measurements on both A-side and B-side rotor sectors, leaving wear trend data incomplete for this cycle. Heavy product accumulation is visible on the rotor vanes, around the valve base, and on the surrounding deck plate. Drive train, switchgear, VFD, and combustion air damper hardware all inspected clean with no mechanical defects identified. Schedule a cleaning intervention and re-attempt gap measurements before the next reporting cycle.
Prioritized actions
- 1 WARNINGClean rotor vanes and housing bore, then complete A-side and B-side vane tip gap measurements
- 2 WARNINGRemove product buildup from valve base, deck plate, and surrounding floor area
- 3 INFOInspect rotor end plate wear pattern once vanes are cleaned and document baseline
- 4 INFOVerify housing bolt flange and base anchor torque during cleaning shutdown
- 5 GOODContinue routine monitoring of switch valve AC drive, gear mesh, and damper actuators
Findings
Findings
1234Fresh air and purge dampers photographed from grade, both electric actuators mounted and intact. Square duct housing and the silo wall penetration show no leakage or deformation. No action required.
Maintain on standard PM cycle; verify actuator stroke during next functional test.
123Switchgear assembly and housing bolt flange inspected clean, but the deck plate around the valve base shows significant product accumulation. Buildup at this location masks any developing leakage at the flange and creates a housekeeping hazard.
Vacuum and remove floor debris around the valve base, then re-inspect the flange face for seepage.
123Heavy product is packed onto the rotor vanes and across the visible rotor end plate, with a wear pattern beginning to form at the rotor hub. The switch gear housing itself is intact, but the vane fouling is what blocked gap measurements elsewhere in this walkdown.
Clean vane faces and rotor end plate during the next planned outage and photograph the hub wear pattern for trending.
1234Excess dust coats the valve body and lower housing. Drive gear mesh and switch gear housing are sound, and the base mount anchor bolts are seated with no looseness.
Include this valve body in the cleaning scope and confirm anchor bolt torque while access is open.
123Burner walkdown covered burner stone, nozzle, gas train, gas transmitter, mount, and combustion air damper. Damper linkage is aligned, handwheel actuator is in its normal position, and the mount bracket shows no deformation.
No action required; retain on standard burner PM interval.
123B-side rotor diagram shows vane positions B1 through B26 with the central hub as datum. Tip clearance measurements at the housing-to-vane interface could not be obtained because product buildup obstructed access to the gap stations.
After cleaning, perform full B-side tip clearance sweep and log values against the B7–B26 station map.
123A-side rotor diagram identifies tip gap measurement stations A1 through A26 indexed off the central shaft datum. As with the B-side, process buildup prevented feeler gauge access at the housing bore stations, so no clearance data was captured this cycle.
Complete A-side tip gap measurements at all 26 stations once the rotor and bore are cleaned; flag any station exceeding OEM clearance limits.
123Switch valve AC drive HMI shows 0.00 Hz with the drive stopped at time of inspection. Keypad legends (FWD/REV/EXT) are intact and the Rotary Valve Motor VFD HMI identification label is in place.
No action required; verify drive parameters at next controls PM.
123Switch valve drive assembly shows correct gear mesh engagement between drive and pinion, with clean wear pattern and no chipping on the tooth flanks. Valve shaft coupling hub is seated correctly.
No action required; continue lubrication on existing schedule and re-inspect gear teeth next cycle.