This incident was reported by a worker that was aboard the ship at the time of the failure. On the day of the accident, the boat was on-shore unreeling pipe from an on-board reel. A winch was used to help with the removal of the pipe from the reel during the final phase. The winch was under tension just before the event occurred. It was at this time that the worker mentioned to their supervisor that they believed that the base plate under the winch was flexing. When the winch finally came to a complete stop the welds that held the winch to the deck suddenly came apart. This resulted in the winch breaking from its sea-fastenings and hurtling along the deck in such a way that the winch and base plate crushed his left leg.
There was an investigation by the members of the IMCA (International Marine Contractors Association). Their investigation discovered a few major pieces of information as follows:
• About two months prior to the sea-fastening welds breaking, the base plate and attachments began to buckle underneath a load. The attempted fix was to add more weld to the base to hold it where it was.
• There was initially a 32Te constant tension winch which was malfunctioning on multiple occasions. It was replaced with a 10Te winch.
• The new 10Te winch that was installed was not constant tension, but also was not even fitted with a tension measurement.
• If the Management of Change process was completed, it did not correctly identify that the new winch was inadequately fastened to the deck.
• When the initial event occurred two months prior to the incident in question, it was not investigated and fixed in an acceptable way. This could have significantly contributed to the break on this particular day.
Here are some of the investigation teams ideas’ on how this situation could have been avoided.
• One of the main priorities should have been to identify all problems with the Management of Change requirements, and fix these problems immediately.
• When the winch was changed, a structural engineer should have been asked to check the position and sea-fastenings to ensure the load on the winch wire could be adequately transferred to the vessel deck structure.
• In situations where welds are in tension, often the case for winches, all welds including under deck welds should be non-destructively tested (NDT).
The result is a very serious lost time injury which is going to require time, money, and medical attention to rectify. Had the event occurred just a split second earlier this accident could have easily resulted in death? Additionally, if the vessel was offshore at the time, it may have been impossible to get the required medical attention in a timely manner. An injury like this can remain with the worker for the rest of their life. A safety incident like this will remain with the company for a very long time.
This is just part of the investigation that was done by the IMCA the entire report can be read in the IMCA Safety Flash 12/14 Newsletter.
The incident detailed above could have been avoided by having Seafasten Offshore review the challenges at hand. Seafasten Offshore is the world leader in engineering design of vessel seafastening solutions and sea transport. If you are unsure about the condition, or adequacy in which cargo or equipment has been secured to a vessel’s deck it is best to ask an expert. Contact Us @ seafasten.com