For a vessel approaching port after a long sea passage, it is essential to ensure that all deck hydraulic cranes, winches, and mooring machinery are in reliable working condition. Continuous exposure to salt spray, humidity, and long periods of inactivity can lead to corrosion, stiffness, or deterioration of hydraulic systems. Therefore, a systematic and well-planned maintenance routine must be carried out to avoid any failure during cargo handling or mooring operations.

1. General Preparation and Visual Inspection

The maintenance should begin with an overall inspection of the deck machinery and surrounding areas. All protective coverings such as canvas sheets, lashings, and weatherproof tapes must be removed from control panels, limit switches, and exposed components. The crane pedestals, winch foundations, and supporting structures should be carefully examined for signs of cracks, deformation, or excessive corrosion that may have developed during heavy weather conditions. It is also important to ensure that all working areas are free from loose items, obstructions, or stored materials that could interfere with safe operation.

2. Hydraulic System Maintenance

Since cranes and winches primarily depend on hydraulic power, the hydraulic system requires thorough attention. The oil level in the hydraulic reservoirs should be checked and topped up if necessary. The condition of the oil must also be assessed; a milky appearance may indicate water contamination, while foaming suggests air ingress. Filters should be inspected by checking differential pressure indicators, and clogged elements must be replaced to maintain proper flow. All pipelines, hoses, clamps, and connections should be examined for leakage, cracks, or bulging. Additionally, the cooling arrangement for the hydraulic oil—whether air-cooled or water-cooled—must be verified to ensure that overheating does not occur during continuous cargo operations.

3. Lubrication and Greasing

During long voyages, exposed moving parts may lose lubrication, leading to wear or seizure. Therefore, all lubrication points must be serviced using a grease gun. Bearings in crane slewing rings, sheaves, and winch drums should be properly greased. Open gears, such as those used in crane slewing mechanisms and winch drives, should be coated with suitable open gear lubricant. Wire ropes used for hoisting and luffing must be inspected for dryness, corrosion, or broken strands, and dressed with appropriate wire rope lubricant to maintain flexibility and reduce internal friction.

4. Brake and Clutch Checks

The braking system is critical for both cargo handling and mooring safety. Brake linings should be inspected for wear and checked to ensure they are free from oil or grease contamination. The effectiveness of brakes must be tested, confirming that spring-applied (fail-safe) brakes engage properly when hydraulic pressure is released and fully disengage when pressure is applied. Clutches should be operated to confirm smooth engagement and disengagement without sticking or slipping.

5. Electrical and Control System Checks

All electrical and control components must be tested to ensure safe operation. Limit switches for hoisting, lowering, and slewing should be physically tested to confirm proper functioning. Emergency stop buttons at local and remote stations must be checked to ensure immediate shutdown capability. Control levers or joysticks should move smoothly and return automatically to the neutral position, indicating correct spring action and control responsiveness.

6. Operational Trials (Dry Run)

Finally, a full operational trial should be conducted at least 24 hours before arrival. Each crane and winch should be run without load through its complete range of motions, including hoisting, luffing, and slewing, for a sufficient duration. This helps circulate hydraulic oil, remove stiffness, and bring the system to operating temperature. If any maintenance work has been carried out, the system should be properly bled to remove trapped air. Mooring winches, especially those fitted with auto-tensioning systems, should be tested to ensure they can maintain line tension effectively during berthing.