Author: Daniel G. Teleoaca – Marine Chief Engineer

The vastness of the ocean demands equally impressive feats of engineering. Marine vessels rely on a complex network of lifting equipment to handle everything from cargo and anchors to delicate research equipment.

Lifting Equipment Onboard Vessels

Here’s a breakdown of some commonly found lifting equipment onboard vessels:

• Deck Cranes: These are the workhorses of modern cargo ships. They are hydraulically powered and capable of lifting and moving a wide range of cargo across the hold or onto the pier.

• Derrick Cranes: Often found on smaller vessels or those handling project cargo, derrick cranes have a fixed mast and a moveable boom that can be raised or lowered.
• Engine Room Overhead Cranes: These are specialized types of cranes designed for lifting heavy machinery and components within the confines of a ship’s engine room.
• Davits: These are typically smaller cranes used for specific purposes like launching lifeboats, rescue vessels, or pilot boats.
• Winches: While not technically cranes, winches are essential for lifting and lowering heavy objects using cables or wires. They are often used in conjunction with other lifting equipment.

This isn’t an exhaustive list, and specialized vessels might have additional equipment suited to their unique needs.

Lifting Equipment Load Testing

As per the regulations, every lifting appliance is to be tested and thoroughly examined before being taken into use for the first time, after any subsequent alteration or repair that may affect the strength of the appliance, or at certain Periodical Surveys with some variations.

Here’s a breakdown of the testing bodies:

• Classification Societies (Class): These organizations establish and enforce safety standards for ship design, construction, and operation. Examples include American Bureau of Shipping (ABS), Lloyd’s Register (LR), and DNV.
• International Marine Contractors Association (IMCA): This industry body publishes guidelines for the safe use and maintenance of marine lifting equipment.

The specific regulations and testing intervals will depend on the type of equipment, its rated capacity, and the classification society or IMCA guidance applicable to the vessel.

• Deck Cranes, Derrick Cranes, and Engine Room Cranes: These fall under the category of “lifting appliances” in the Classification Society and IMCA guidelines. A lifting appliance forms an essential feature of a vessel if the purpose of the vessel is predominantly to support the appliance, and the purpose of the floating structure is impaired if the appliance is not functioning. They require periodic load testing, typically every 1–5 years, depending on the specific regulations and the severity of duty.
• Davits: Treated similarly to cranes, davits used for essential life-saving equipment (like lifeboats) might have stricter testing requirements, with some regulations mandating testing more frequently than other cranes. Usually, classification societies like ABS or DNV typically require load testing of lifeboat davits every 1-5 years, depending on the specific regulations and how often the davits are used. The International Convention for the Safety of Life at Sea (SOLAS) plays a major role in lifeboat davit testing. SOLAS Chapter III, Regulation III/20, mandates that davits for lifeboats and rescue boats be tested with a static load test at least every five years. This test involves applying a weight equal to 1.1 times the total mass of the fully loaded lifeboat (including people and equipment) to simulate a worst-case scenario.
• Winches: Winches are considered “loose lifting gear” under IMCA regulations. They are also included in Class guidelines for periodic functional testing and proof load testing. The testing frequency for winches may differ from cranes depending on their usage and criticality.

Why Load Test Marine Lifting Equipment?

Imagine a massive container ship attempting to raise a thousand-ton anchor with faulty winches. The consequences could be catastrophic. Load testing acts as a vital safety check, identifying potential weaknesses or defects in the equipment before they lead to accidents. Here’s why it’s crucial:

• Safety First: Load testing ensures the lifting equipment can handle the maximum rated load (SWL) without compromising its structural integrity. This safeguards personnel, cargo, and the vessel itself.
• Regulation Compliance: Maritime regulations set forth by bodies like the International Marine Contractors Association (IMCA) mandate regular load testing for various lifting equipment.
• Peace of Mind: Regular testing provides valuable data on the equipment’s health, allowing for preventative maintenance and extending its lifespan.

The Load Testing Process: A Balancing Act

The specifics of a load test will vary depending on the type of equipment being tested. However, the general process follows these steps:

• Planning and Preparation: A qualified engineer will assess the equipment and create a detailed test plan outlining the test loads, procedures, and safety protocols.
  • Where testing machines (e.g. dynamometers) are used to apply test loads, they are to be of a type approved by the Class as suitable for the intended purpose.

• • The machine is to be calibrated biennially by a recognised authority, and the accuracy is to be within ±2 %.
  • Testing machines are not to be used for initial testing; and although acceptable to the Class for periodical re-testing or following repairs, some National Authorities will not accept this form of testing.
• Test Weight Selection: Choosing the right weight is critical. Typically, the test load will exceed the SWL by a specific factor (often 1.25 or 1.5 times) to account for dynamic forces during operation. Water bags or calibrated weights can be used.

Where test weights are used to apply test loads, the weights are to be certified as accurate to within 2 %.

• The Test Itself: The equipment is gradually loaded with the test weight, and its performance is meticulously monitored. This includes checking for deformations, cracks, or malfunctions in various components like ropes, hooks, and brakes.

Measures are to be taken to ensure that the appliance can be controlled during the test and to avoid injury or damage that might occur in the event of a failure under load. Lifting appliances are generally to hold the test weights for at least 5 minutes, but this may be extended at the discretion of the Surveyor

• Documentation and Certification: Upon successful completion, a detailed report is generated documenting the test procedures, results, and any observations. This report serves as a crucial record for future reference and regulatory compliance.

Additional Considerations

While the core process remains consistent, there are additional factors to consider for a comprehensive load test:

• Equipment Specificity: Different lifting equipment, like cranes, winches, and davits, will have their own testing procedures and considerations.
• Dynamic vs. Static Testing: Real-world lifting operations involve dynamic forces. Some tests incorporate these forces to provide a more realistic assessment.
• Competent Personnel: Only certified and experienced personnel should conduct load testing to ensure safety and adherence to regulations.

In conclusion, load testing is not just a regulatory checkbox; it’s an investment in the safety and efficiency of your marine operations. By proactively identifying and addressing potential issues, you can prevent accidents, protect your crew and cargo, and ensure your vessels continue to navigate the seas with confidence.

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Video Source and Credit:

• Virtual Guru – Youtube;
• akashsince1996 – Youtube
• chiefengineerlog.com – Water bag test video