Britannia Club emphasizes the indispensable role of cranes in shipboard activities, facilitating efficient cargo handling and supporting diverse maritime functions.
Cranes play a vital role in shipboard operations, facilitating the efficient loading and unloading of cargo, and supporting various maritime activities.
As explained, they are essential for lifting heavy loads, and their inspection, maintenance, and certification are crucial for ensuring the safety of personnel and the protection of valuable cargo.
According to Minton, Treharne & Davies Group (MTD), every crane on board a ship should have a manual from the manufacturer that provides recommendations on hot to operate the cranes and guidance on inspections.
The manual should also be used to create a planned maintenance regime that includes the manufacturer’s recommendations. This planned maintenance regime should be incorporated into the ship’s Safety Management System procedures. All required maintenance, inspections, and testing of each crane should be
carried out at appropriate intervals. These intervals may be determined by factors such as:
- Discharge of abrasive cargo (additional greasing of unsealed bearings may be required)
- Crane running hours, or regular time intervals, such as monthly checks. Recognise the significance of conducting maintenance based on running hours, as it proves invaluable in predicting potential failures by comparing actual usage with the expected lifespan of specific components. As a result, take
preventive measures promptly to avoid downtime and mitigate the risks of failures.
Wire rope lubrication is essential and serves two purposes: internal and external lubrication, as well as corrosion protection. It is crucial to avoid using grease for this purpose. Wire strands experience movement against each other when the wire is tensioned or passes over sheaves. Therefore, using wire rope lubricant ensures penetration into the core of the wire, whereas grease tends to sit on the surface, potentially getting washed off or contaminated with cargo dust, leading to the formation of a thick layer on the wire’s surface.
It’s important to note that during a visual inspection of wire ropes, only the visible parts of the outer wires can be assessed. These outer wires constitute around 40% of the total cross-section of the wire rope, and even then, only about half of their length is visible. Consequently, a visual inspection can only cover approximately 20% of the wire rope. Unfortunately, it is common for the visible 20% to appear undamaged, while hidden wire breaks may be present in the remaining unseen portion of the rope. Wire ropes with internal wire breaks and no external signs of damage pose a high level of danger.
Crane hydraulic systems rely on high-quality hydraulic oil for smooth and efficient operation. Shipowners should establish a proactive oil analysis program to monitor oil condition and detect potential issues, such as contamination or degradation. Regular oil sampling and testing, along with appropriate filtration and oil changes, will help to keep the crane’s hydraulic system in optimal condition.
Regular inspection and cleaning of the oil cooler is also essential, especially when the cranes are operated in high ambient air temperatures. If the ship frequently loads and unloads dusty, or corrosive cargoes, the cleaning may be required more often. Neglecting to clean the oil cooler could cause the crane to cut out once it reaches the high temperature limit, leading to potential performance issues if the cranes repeatedly stop functioning. Timely attention to hydraulic oil leaks is crucial. Aside from being a safety hazard, failure to address these leaks may result in stevedores refusing to use the cranes altogether. Therefore, it is imperative to address oil cooler maintenance and hydraulic leaks promptly.
Crane safety devices, such as load indicators and limit switches, are critical for preventing accidents and ensuring safe operations. Verify the functionality of these safety devices by conducting inspection and testing before discharging or loading. Shipowners should establish procedures to address any malfunctioning safety devices promptly. A competent member of the crew should test safety devices related to load handling for gantry cranes, along with testing trolley slowdown and stop limits, as well as gantry movement alarms (both visual and auditory), emergency stops, and obstruction stops before using the crane.
Luffing and slewing usually have a key-operated by-pass switch for the lower limit of the jib, specifically utilised when stowing the jib. It is important to ensure that the key is never left in the crane, and precautions should be taken to prevent accidental operation of the switch. Stevedores’ requests to make override keys available (which may be the standard practice is some ports) should be resisted. The jib should only be operated below its lower limits when it is being stowed. Operating the jib below its lower limit while there is a load on the hook can result in the jib or the luffing wire coming off its drum, potentially causing failure.
Once the pre-operation checks have been conducted, the following should be considered, the list below is not considered exhaustive:
- Conduct a meeting with the stevedores to discuss the discharge plan and verify the grab’s working condition, fault indicators, means of communication with the ship, and the presence of a signaller/banksman
- Ensure sufficient lighting in the cargo spaces
- Report any equipment faults to the terminal representative immediately
- Report any damages to the ship’s structure, regardless of their impact on seaworthiness, and raise a stevedore damage report
- The duty officer and other crew members on watch should monitor all crane handling and document any concerns immediately
- During cargo operations, ensure that all limit switches remain functional and refrain from overriding them.
- Override or bypass of a limit control is only allowed under exceptional circumstances and must be conducted under the direct supervision of senior ship’s personnel.
- Avoid any such actions during regular cargo operations.
