Klöckner VDG 16/60 / C1

Common issues

• Vane and stator seal wear leading to internal hydraulic bypass and reduced holding torque
• Hunting or sluggish rudder response caused by air entrainment in the hydraulic system
• Shaft seal/gland leakage allowing seawater ingress at the rotor casing
• Relief valve drift causing premature pressure relief before design torque is reached
• Non-return valve leakage allowing rudder creep when the gear is stopped
• Coupling and keyway wear between the rudder stock and rotor housing
• External leakage at rotor casing joints and pipe connections

Inspection checklist

• Check oil level and condition (water content, particulates) in the header tank
• Verify rudder angle indication agrees between local, steering flat and bridge readouts
• Function-test both power units and the changeover between them
• Check for external leakage at casing joints, shaft seal and pipe connections
• Confirm relief and non-return valve settings against the approved test certificate
• Confirm isolating valves are locked open as required by SOLAS
• Test power failure, low oil level and phase failure alarms locally and at the bridge
• Verify emergency/local control changeover procedure
• Check rudder stock coupling bolt torque and keyway condition
• Check mechanical and hydraulic rudder stops are intact

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Vane and stator seal set
• Shaft seal / gland packing
• Relief valve
• Non-return valve
• Rotor casing gasket/O-ring set

Safety

• Stored hydraulic energy - isolate and depressurize before opening any joint
• Rudder can move unexpectedly if isolating valves are not locked during maintenance
• Heavy rotor casing components - confirm lifting gear capacity before removal
• Confined working space in the steering flat around a moving rudder stock

Class survey

Steering gear is a Continuous Survey Machinery item; class typically requires an annual function test with changeover, a full-stroke test at each renewal/special survey, and verification of relief valve settings and rudder stock coupling integrity. The DNV type approval certificate (TAW000036C) and maker's test records should be retained on board.

Estimated lifetime: Rotary vane steering gear units of this class are typically designed for the vessel's full service life (around 20-25 years) provided seals, bearings and hydraulic components are renewed per the maker's schedule.