RV 850-3

Häufige Probleme

• Internal leakage past vane seals, reducing holding torque and allowing rudder creep under load
• External hydraulic leakage at shaft seals, pipe unions or manifold block joints
• Contamination of hydraulic oil causing valve sticking or erratic rudder response
• Wear or scoring of vane tips and stator surfaces, reducing volumetric efficiency
• Loose or worn tiller/rudder stock coupling causing backlash
• Overheating of hydraulic oil during sustained heavy-weather steering
• Failure or drift of the rudder angle feedback/transmitter unit

Prüfliste

• Function test of both steering gear power units and changeover under way (SOLAS test before departure)
• Check hydraulic oil level, condition and cleanliness (sample/particle count if due)
• Inspect pipework, unions and the vane housing for leakage or weeping
• Measure rudder response time hard-over to hard-over against the vessel's approved figures
• Check alarm and indicator systems (rudder angle indicator, power failure alarm, low oil level alarm)
• Inspect relief valve settings and isolating valves for correct operation
• Check tiller/rudder stock coupling bolts for tightness and coupling for backlash
• Verify emergency steering arrangements and changeover procedure are demonstrated

Wartungsintervalle

Typische Intervalle für diese Bauart, keine Herstellerangabe für Ihr Modell. Verbindlich ist das Handbuch des Herstellers.

Typische Verschleißgrenzen

Die Bereiche sind für diese Bauklasse typisch. Maßgeblich sind stets die Herstellerunterlagen zur jeweiligen Seriennummer.

Kritische Ersatzteile

• Vane seal and O-ring kit for the ram/vane assembly
• Shaft seals for the rotary actuator
• Hydraulic pump/motor unit seal kit
• Relief and changeover valve spares
• Rudder angle transmitter/feedback unit
• Hydraulic filter elements
• Coupling bolts and locking arrangement for the tiller/rudder stock

Sicherheit

• Stored hydraulic energy in the system - isolate and depressurise before opening pipework or the ram/vane housing
• Rudder can move unexpectedly if isolating valves are not correctly set during maintenance - lock out the steering gear per procedure
• Heavy components (vane rotor, covers) require proper lifting arrangements
• Confirm emergency steering communications and manual changeover are understood by the crew before relying on them

Klassenbesichtigung

Steering gear is Continuous Machinery Survey eligible on many class rules; surveyor checks the SOLAS steering gear test record, changeover test, main and auxiliary power unit operation, alarms, and rudder angle indication against the helm. Internal examination of the vane/ram assembly is typically required at a fixed interval (commonly 5-yearly) or on condition.

Geschätzte Lebensdauer: Rotary vane steering gears of this class are generally designed for the vessel's full service life (20-25 years) with periodic seal, bearing and valve renewal, rather than treated as a wear-out component on a running-hours basis.