TT Talk - Does your ASC equipment have travel anti-collision?
Increasingly sophisticated handling equipment is being installed in various parts of the world, often enabling automated operations. Ensure that your investment adequately reacts to real life scenarios.
Recent incidents involving Automatic Stacking Cranes (ASC) at terminals in two different parts of the world have exposed a serious and potentially common omission by equipment manufacturers. Both incidents involved containers being blown from the stack in the automated stacking yard during adverse weather conditions. Subsequently, the ASC carrying out operations in the area have, while long travelling, ploughed into the containers that were lying across the crane rails. This type of incident can cause damage to the affected containers, but more significantly also to the ASC itself and the crane rails. Furthermore, when an ASC partially derails, there is a risk of further collisions with neighbouring equipment in the automated yard and severe operational delays.
Think collision risks
Initial investigations revealed that the cranes did not have any travel anti-collision systems installed. Further enquiries found some ASC manufacturers are purposely not providing travel anti-collision sensors claiming that such technology is not required or can inadvertently impair the performance of the cranes. In TT Club's opinion, this demonstrates flawed reasoning, based on one of the key assumptions that the collision risk is avoided since personnel and vehicles are prohibited in the automated stacking yard whilst it is in operation.
It is true that whilst operating in normal circumstances the collision risk between two or more cranes is effectively mitigated by their positioning measurement control system. In this limited scenario, the cranes do not require travel anti-collision sensors to prevent any collision between them. Another argument that has been raised is that sensors would identify temporary obstacles, such as small wildlife or plastic bags, causing the ASC to stop operations and require a reset, resulting in delays to operations.
Clearly, the technology needs to take account of the potential that containers can be blown from the stack and other items might hinder the crane's passage. Furthermore, and more importantly, even though personnel and vehicles should not be in the automated stacking yards during operation, there cannot be a guarantee that it will not happen. Lastly, the systems should be capable of detecting fleeting obstacles and respond accordingly, including devising an automatic reset function, resulting in no delay.
"the technology needs to take account of the potential that containers are can be blown from the stack and other items might hinder the crane's passage"
Joint specification guidance, compiled by TT Club with PEMA and ICHCA and published in 2012, states that all ASC equipment should have an electronic travel anti-collision system to protect lives and property. Manufacturing without such systems is a serious safety omission and compromises safety.
TT Club recommends that those terminals that have installed ASC equipment verify whether an electronic travel anti-collision system is installed and operational on all items. Where such systems are not installed or operational, the terminals should take the necessary action to protect their investment, operations and personnel. Furthermore, the Club is urging all ASC manufacturers to ensure they include electronic travel anti-collision systems as a standard on all ASC equipment.
The incidents that have occurred demonstrate what is possible in terms of potential damage to the ASC equipment, rails and other infrastructure, container units stacked in the area, not to mention the operational downtime to clear debris and affect repairs and ensure that no hidden damages have been incurred.
We hope that you have found the above interesting. If you would like further information, or have any comments, please email us, or take this opportunity to forward to any colleagues who you may feel would be interested.
We look forward to hearing from you.
Risk Management Director, TT Club