Stopping Distance Of A Bridge Crane- How To Calculate It?

To perceive the OSHA standards, you have to calculate the stopping distance of a bridge crane. Otherwise, there is a possibility that the crane will travel too far once you release the button of your remote. Therefore, one of the important things that you have to keep in mind is that you have to follow the guidelines of OSHA (Occupational Safety and Health Administration) and ASME B30. So, here we will talk about stopping distance and how to calculate it. It will be an insightful discussion for you if you are dealing with bridge cranes. Some of the guidelines that you have to take into account are:

• OSHA 1910.179(f)(4)(vii) states that the bridges and the trolleys should come with considerable sizes of brakes. To be precise, the brake should be capable of stopping the bridge or trolley at least at a distance of 10% compared to the full speed. The unit of the speed should be in feet per second. The brakes should achieve this stopping distance when the trolley or bridge travels at full speed along with the full load.
• ASME B30.2-1.12.3 (a)(1) says that the brakes should have powerful torque. It must stop the bridge or trolley while moving a distance equal to 10% of the ‘rated load speed. However, you have to make certain of the fact that the bridge or the trolley is carrying the rated load.

You should know that the ‘rated load speed’ of a crane is the speed set by the manufacturing company. To know the speed of a crane, you can go through the specification section of the manuals. However, in case you don’t find the speed, there are procedures to calculate them. We will mention you two processes, and amongst them, you have to choose one according to your preference.

• The best option for you is to determine the 10% of a minute. If you take a look at the standard, you will find out that it states, “10% of full load speed in meter per minute.” Well, 10% of a minute is 6 seconds. Therefore, whenever the trolley or the bridge is travelling at full speed and full load, it should take 6 seconds to stop once you press the off or neutral position. If the load is less than the rated load, the trolley or bridge will drift less than 6 seconds.
• There is another way to calculate the stopping distance. Here, you have to ascertain 10% of the distance, and its unit should be feet. The first thing you must do is load your crane and allow it to traverse for one minute at full speed. Note down the distance that the crane is travelling. In the case of most trolleys, they will go out of the room, and it will not take one minute. Thus, you have to take 10% of that distance, which will be its maximum ‘drift’ distance you must allow. In simple words, your crane should not drift more than drift distance once you turn off the crane. It is one of the common approaches that most people take, but it is a tiresome process. It will take plenty of time to calculate with the help of this process.

The factors that impact the stopping distance

We know speed is the most imperative factor when it comes to stopping distance. Apart from that, some other factors impact the stopping distance as well. Knowing these factors will help you to achieve accuracy while determining the stopping distance. Those factors also have a significant role to play when it comes to safety. Considering those factors will enhance the general safety of your facility. Here is the list of the factors.

• Absence of scanning techniques.
• Distracted operation of the cranes.
• Poor knowledge on the areas that comes with high risk.
• Improper condition of the brake pads.
• Condition of the operators.
• Poor traction.
• Limited visibility.
• Type of the braking system that you are using.

Important components of the stopping distance

Apart from those factors, you have to consider some other major components while calculating the stopping distance. Those major components are:

• Perception distance: Here, we are talking about visual perception. Each individual will come with a unique perception. Experience also has a pivotal role to play to ensure the perception of an individual. For instance, if the operator has the required experience, their visual perception will be almost accurate.

• Braking distance: The purpose of braking is to slow down the speed of the crane. So, the braking distance is when the operator applies the brake to the point where the vehicle stops.

• Reaction distance: Reaction distance is also one of the substantial components that influence the stopping distance. It depends on the external stimuli. You can determine the reaction distance by calculating the distance between the operator's points using the brake during external stimuli and when the crane stops.

So, this is how you should calculate the stopping distance of a bridge crane. Also, take a look at the factors that impact the stopping distance of the crane. It will help you establish a safer environment. Your workers, along with your facility, will stay safe if you take those factors into your account seriously.