By Frédéric Lévesque
Installation Director
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In short... Discover 8 common problems during overhead crane installation. This article explores the causes of these problems, but above all what can be done to avoid them, so that your installation runs smoothly and without additional costs.
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It's finally the "D" day for your overhead crane installation. You're looking forward to using your new lifting equipment. But then you receive word that the installation isn't going as planned, and that they're not yet operational. What's more, you realize that this problem could have been prevented and that it will result in additional costs. You witness, powerless and frustrated, a scene that could have gone differently.
To help you avoid this disappointment, we've compiled a list of 8 common problems when installing an overhead crane. After reading this article, you'll not only know what the most common problems are, but also what causes them and what you can do to avoid them.
Problem 1 – Power supply unavailable or missing
Once the overhead crane has been installed on the rails, it's time to make the connections. A power supply must be available at the time of installation, as the equipment must be tested before it can be used. This may seem obvious, but it's often overlooked.
Unavailable power supply
Before installation, the power supply must be ready for use. To be precise, this means that the building connection must have been have been finalized, and an electrical cable brought close to the conductor bars to enable connection. This is the electrician's responsibility. Without this step, the installation team will not be able to finalize the installation. The consequence? They will have to come back to finish the job, which is called a second mobilization. In addition to these unforeseen costs, you'll have to plan again for the rental of equipment for working at height, and perhaps also for load-testing equipment. These costs will then be doubled.
Solution
Make sure well in advance that the power supply will be available on the day of installation. If not, plan a temporary connection for the day of installation.
Phase reversal
What is phase reversal? As mentioned in the previous point, crane installation is often carried out with a temporary electrical connection, before the permanent power supply arrives.
However, when connecting the permanent power supply, the electrician may reverse the phases, which also reverses the overhead crane's functions. As a result, when you press the "down" button, for example, the hoist now starts to move upwards! This may seem harmless, but damage can occur if the hoist is moved in the opposite direction to the intended motion.
Solution
In this case, a check by your lifting specialist may be advisable at the time of permanent connection. He or she will check the direction of rotation when the power is switched on. This will cost you a 2nd mobilization but may prevent more serious problems.
Problem 2 – Missing or incorrectly positioned end stops
End stops are blocks, usually made of steel, which stop the travel of the overhead crane at the ends of the rails. They are necessary to ensure safe crane operation.
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What is the overhead crane or hook approach The overhead crane approach is the closest position a lifting hook can reach to an obstacle (e.g. a wall), while remaining functional and safe. |
There is often a confusion as to whether this component will be included by your overhead crane supplier or by the general contractor supplying the structure.
In other cases, the ends stops are present but need to be repositioned. Why? Either because there is an obstruction to the crane's movement, or to maximize the crane's approach (see box "What is the overhead crane or hook approach").
What are the consequences? Incorrectly positioned end stops can restrict the hook's approach at this end. If they are misaligned, they could damage the crane. And finally, accidents can happen if the end stops are missing or inadequate. This situation needs to be rectified, which can cause delays in the installation work, potentially affecting the schedule.
Solution
Good communication between the various parties involved is the key to preventing such problems. To avoid any confusion, it is recommended to check with the overhead crane supplier who will supply the rails and end stops, as soon as the contract is signed. As for the positioning of end stops, the approach to the hook should be determined at the start of the project. Obstructions will be covered in Problem 5.
Problem 3 – Structure misalignment
The alignment of the structure is very important to ensure that the overhead crane runs smoothly on the rails. The CMAA standard specifies the alignment tolerances to be respected. You can download the table of tolerances here. When this isn't the case, the structure must be realigned before the rails are installed.
Solution
To ensure alignment within standard tolerances, a report can be requested from the overhead crane structure manufacturer. Even if the structure was not supplied by the lifting equipment manufacturer, he may be able to help you by transmitting the required tolerances to the structure company from the outset.
Problem 4 – Renting the wrong equipment for work at height
Your overhead crane manufacturer knows what equipment needs to be rented to install your overhead crane safely. But sometimes, the customer himself takes care of this aspect. Even then, the overhead crane manufacturer can indicate you what they will need for installation. But if the installation team finds that the equipment is inadequate, it will have to be replaced, which will mean work delay.
Solution
Of course, renting precisely the equipment recommended by your overhead crane supplier will avoid this problem. The other option is to provide the project manager with the nameplate of the equipment you plan to use to carry out the work. This will enable him to check and ensure that it is appropriate.
Problem 5 – Obstruction by building mechanics
A common surprise when installing an overhead crane is the presence of building mechanics that conflict with the installation plan. This could be a garage door or a ventilation duct, etc. As a result, the installation cannot be carried out without modifications. Either the mechanical element interfering with the installation has to be modified, or the configuration of the overhead crane itself has to be altered. This can lead to delays in the installation, as well as costs, which can be significant.
Solution
Communication between the various parties involved remains the key. The future overhead crane owner could, for example, provide the overhead crane plan to the various parties involved in the project. This is an example of good practice.
For more information on this subject, see the article "Overhead crane clearances: Why and how to avoid problems" .
Problem 6 – Floor inadequate for work
Certain types of ground can complicate the installation of an overhead crane. For example, when the concrete floor is not yet installed, the floor is often gravel, or even dirt. These types of ground are more unstable.
In other cases, the outside terrain is not finished either. The gravel ground at the building’s entrance is therefore lower than the foundation, both on the inside and the outside. This exposed foundation then becomes an obstacle for the trailer or installation equipment, since there is no access ramp to drive on.
It should be also noted that delivery via a loading dock often proves to be more complicated, as it generally requires more equipment and two teams to unload the material.
So, what are the consequences of these situations?
Unstable grounds often require different work equipment. This situation will also extend the time required for the work. All this adds to installation costs. Sometimes the ground is too uneven for the work to be carried out, for example if it has not been levelled or if the edges have not been filled in.
Solution
The best solution is to plan the work once the floor work has been completed, both inside and outside.
Problem 7 – Inadequate storing
As we all know, Quebec has a harsh climate. When an overhead crane is stored in a building not sheltered from the elements, electrical parts can get damaged. In an installation context, this can happen in two circumstances.
Firstly, when an overhead crane is temporarily stored in a building while awaiting installation, but the building is unheated. For example, the installation site may not yet be ready to receive the lifting device, and the supplier may not have the space to store it at his plant. The customer then has to store it temporarily.
Secondly, when the overhead crane is installed in a building that has not yet been finished and is therefore still exposed to the elements. This may be the case when the building is not yet connected to the power supply, or when the roof or walls have not been finalized.
Solution
Ideally, the installation of an overhead crane should take place when the building's structure is finalized and the power supply and heating units are in place. Through good communication with your crane supplier, it will certainly be possible to plan the installation in line with the building's construction schedule. But if this isn't possible, or if the equipment has to be stored in an unheated building, it's advisable to remove certain parts from the overhead crane that are sensitive to temperature and humidity variations. Your supplier will be able to tell you which ones.
Problem 8 – Restricted work environment
The work environment can sometimes present challenges, which can vary depending on the company. Here are 3 examples.
Difficult access to the installation site
Certain situations may make it difficult or even impossible to erect the overhead crane on the tracks using a standard procedure (from the ground).
Solution
When this happens, other options need to be considered. For example, the overhead crane could be brought in through an opening in a wall, or through the roof using a crane. But you need to plan ahead, as this requires completely different logistics. Good communication with your supplier before starting the project will avoid any surprises.
Constraints with production
The other case where the environment can be an issue is when the overhead crane installation will interfere with production. If production must be interrupted to enable installation at the designated location, but this interruption would have too great an impact on production, an alternative solution often has to be found.
Solution
Installation can be carried out in the evening or at weekends, but often at higher rates. You'll need to calculate which option is the least costly and plan the work carefully. Since the organization of an installation outside normal working hours is generally more complex, good organization well in advance will avoid problems.
Cluttered environment
On the date of installation, if the workspace at the installation site is not prepared by removing all objects, machines and materials, the time required for on-site work is likely to increase, therefore delaying the start-up of the overhead crane.
Solution
Plan a site preparation phase well in advance to avoid being caught unprepared. You can consult your overhead crane supplier, who will be able to tell you what could affect the installation.
A successful installation is possible!
As mentioned above, it can be frustrating not to be able to use your new lifting equipment on schedule due to installation problems. It can even slow down your production, resulting in financial losses. But it is possible to avoid this situation! By reading this article, you've seen that each of these problems has a solution. They can be summed up in a few words: prevention, organization and communication. By following this advice, your overhead crane is certain to be ready for use when you need it.
What happens next? Before using a piece of equipment that has just been installed, it's wise to make sure that no steps have been forgotten or neglected. For example, has a load test been carried out in accordance with CSA B167-16? We suggest you visit our Load test page to learn more about this important subject.
What's more, to get the most out of your lifting equipment over the long term, it's important to maintain it properly. But how? You'll find the answer to this question in the article "What maintenance do I need to do on my overhead crane? How much does it cost?".
Premium Industrial Group specializes in the manufacture of overhead cranes and can support you at every stage of your project. If you want, you can contact your project manager for any questions about your future installation.
