RL Rotary Valve

15 checklist steps · 592 examples · card v1 distilled from 261 · 331 added since
331 new examples since this card was distilled

They're highlighted below with the New tag. Regenerate the card to fold them in.

The 15 steps Luthier walks every technician through for this equipment type. Severity signals show what to flag.

baseline v1
  1. Step 01 · Valve Gap

    Measure valve gap at A2–A26 and B2–B26

    Valve gap clearance is the primary health indicator for the rotary valve; loss of gap leads to seal damage and process leakage between A and B sides.

    Focus: Record clearance at each numbered position on both A and B cylinders; expected range is approximately .010–.015 inches. Flag any zero readings as HIGH severity.
    Severity signals (4)
    • all positions zero clearance → HIGH
    • some positions at 0 with others normal → LOW–MEDIUM
    • measurements obstructed by buildup → MEDIUM
    • all positions within .010–.015 in → NONE
  2. Step 02 · Valve Assembly

    Inspect valve body and surrounding area for process buildup

    Process buildup accumulates on and around the valve assembly, accelerating wear and obstructing gap measurement access.

    Focus: Look for material accumulation on the valve body, seal plate area, and backside of inlet valves. Note whether buildup prevents gap measurement.
    Severity signals (2)
    • light/typical buildup with no functional impact → LOW
    • buildup obstructing gap measurement → MEDIUM
  3. Step 03 · Switch Valve Drive Assembly

    Inspect switch valve drive assembly and AC drive

    The drive assembly actuates the rotary valve; failures here halt switching and the entire RTO cycle.

    Focus: Verify drive assembly and AC drive are intact, mounted securely, and free of damage or oil leaks. Confirm no abnormal sounds or loose hardware.
    Severity signals (2)
    • loose mounting or damage → MEDIUM
    • drive in good condition → NONE
  4. Step 04 · Drive Gear / Gear Mesh

    Inspect drive gear and gear backlash

    Drive gear condition and proper mesh/backlash with the driven gear ensure accurate valve positioning.

    Focus: Examine tooth condition, mesh engagement from top and side angles, and check for excessive backlash or visible wear.
    Severity signals (2)
    • excessive backlash or significant tooth wear → MEDIUM
    • normal mesh, intact teeth → NONE
  5. Step 05 · Valve Driven Gear

    Inspect valve driven gear for wear

    Driven gear wear changes backlash and rotational accuracy, contributing to gap loss over time.

    Focus: Inspect tooth flanks for wear patterns, pitting, or polish. Note any minor wear even when overall condition is acceptable.
    Severity signals (3)
    • minor flank wear, otherwise good → LOW
    • significant tooth wear or damage → MEDIUM
    • no observable wear → NONE
  6. Step 06 · Valve Drive Plate Assembly Mount

    Inspect valve drive plate assembly mount

    The drive plate mount anchors the actuation linkage; loose or damaged mounts misalign the valve.

    Focus: Confirm fasteners are secure, mounting plate is flat, and there is no cracking or distortion.
    Severity signals (2)
    • loose hardware or distortion → MEDIUM
    • secure, intact mount → NONE
  7. Step 07 · Valve Lift Pancake Cylinder

    Inspect valve lift pancake cylinder

    The lift cylinder seats and unseats the valve during each switch; leaks or sticking impair sealing.

    Focus: Check for air leaks, oil weeping, cylinder body damage, and proper stroke. Confirm mounting hardware is secure.
    Severity signals (2)
    • visible leak or damage → MEDIUM
    • cylinder intact and dry → NONE
  8. Step 08 · Main Valve Seal Ring

    Inspect main valve seal ring

    The main seal ring provides the primary sealing surface between A and B flow paths; damage here causes cross-leakage.

    Focus: Look for wear, deformation, embedded debris, or uneven contact pattern on the seal ring.
    Severity signals (2)
    • visible damage or uneven wear → MEDIUM
    • intact, uniform seal surface → NONE
  9. Step 09 · Seal Plate Bowtie

    Inspect seal plate bowtie

    The bowtie seal plate divides A/B flow at the valve face; damage causes flow bypass.

    Focus: Examine the bowtie surface for wear, scoring, or buildup. Confirm proper seating against the valve body.
    Severity signals (2)
    • scoring or wear → MEDIUM
    • clean, intact bowtie → NONE
  10. Step 10 · Valve Spindle Bearing

    Inspect valve spindle bearings (interior and exterior)

    Spindle bearings support the rotating valve shaft; wear causes runout and contributes to gap loss.

    Focus: Check both interior and exterior bearings for play, contamination, grease condition, and unusual wear.
    Severity signals (2)
    • play or contamination → MEDIUM
    • smooth, properly lubricated → NONE
  11. Step 11 · Inlet A Side

    Inspect inlet A-side valve face

    A-side inlet is half of the alternating flow path and is a typical location for buildup and gap loss.

    Focus: Document valve face condition, buildup on backside of inlet, and any abnormalities.
    Severity signals (2)
    • buildup on backside of inlet → LOW
    • clean face → NONE
  12. Step 12 · Inlet B Side

    Inspect inlet B-side valve face

    B-side inlet is the other half of the alternating flow path; condition must mirror A-side for balanced operation.

    Focus: Document valve face condition, buildup, and any abnormalities. Compare to A-side.
    Severity signals (2)
    • buildup or wear → LOW
    • clean face → NONE
  13. Step 13 · Exhaust End of Manifold

    Inspect interior of exhaust end of manifold

    The exhaust manifold collects post-combustion flow; internal buildup or corrosion indicates upstream issues.

    Focus: Look inside the manifold for buildup, corrosion, or insulation damage.
    Severity signals (2)
    • heavy buildup or corrosion → MEDIUM
    • clean interior → NONE
  14. Step 14 · Exhaust Fan Wheel

    Inspect exhaust fan wheel for buildup and balance

    Buildup on the fan wheel causes imbalance, vibration, and bearing wear; even minimal coatings should be noted.

    Focus: Look for coating on blades, asymmetric deposits, and any signs of erosion or damage.
    Severity signals (3)
    • minimal buildup → LOW
    • heavy buildup or imbalance indicators → MEDIUM
    • clean wheel → NONE
  15. Step 15 · Valve Assembly Hardware

    Verify all valve assembly hardware is secure

    Loose hardware on the rotary valve can cause misalignment, vibration, and progressive damage.

    Focus: Confirm bolts and fasteners on the drive assembly, mount, and gearing are tight and undamaged.
    Severity signals (2)
    • loose or missing fasteners → MEDIUM
    • all hardware secure → NONE
© Industria Machina · Demonstration prepared for Dürr
System health: 99.8% Nominal