Cranes must move along runway rails without potential issues. The overall performance of a crane depends on a number of factors, and the most important of them is the runway alignment. Your upfront cost must include a proper alignment of runways. However, most companies using these overhead cranes overlook their runways.
In the material handling industry, it is essential to use a perfectly aligned crane. Incorrect rail alignment may result in the chain reaction, and it will result in wears and tears of rails and wheels. What’s more, you can find downtime at the time of operating cranes. It is stated that end-user has the liability of the tolerance level of the crane. You need to focus on some factors to ensure that the runway is properly aligned-
- Elevation levels
- Runway condition
The crane span must be in nominal tolerance level throughout the system. Likewise, straightness has to be within acceptable tolerance in any direction from the runway. In case of elevation, you have to check out elevation variances below/above the standard rail’s elevation line. To say simply, improper alignment can cause stress on motor drives. Uneven rails and skewing may affect the longevity of the equipment system.
How do you know that your crane runway has problems?
It is not always easy to detect them. Your crane may continue its function silently, and you may not identify that the integrated runway has no alignment. This issue can put strain on the building structure and the equipment. Still, we have found some common signs indicating glitches to your crane runways.
While moving down the runway, your crane will make loud sound. When you have no knowledge about checking runways, you may hire professionals for inspection. These certified professionals will analyze the runway thoroughly based on standard guidelines. According to these guidelines, runways have to be parallel, straight, level, and at a proper elevation. The runway tolerances have to be in any of the four positions-
- Level with the other one
- Parallel to the other one
We have noticed several other signs of misalignment-
- Cracked wheel flanges
- A higher amount of power needed to pass the crane system through the runway
- Abnormal deterioration of rails, wheels, and wheel bearings
- Wheels floating/climbing over the rail
Now, we are going to briefly discuss factors affecting runway alignment.
We have already told that the span must remain within its tolerance. While it is out of tolerance, it will cause adverse effects on your system. You may also find crane racking problems.
For instance, with a span below 15 Meter, the tolerance level has to be about 6 mm. When it is between 15 and 30 Meter, the tolerance level is not different. Similarly, when the span has crossed 30 meter, this tolerance has to be 10 mm.
These are very limited tolerances in contrast to the runway span. While you have gone beyond those tolerances and the rail is misaligned, it can damage brakes within a short time.
Clearances- Vertical and horizontal
Another important factor for the material handling equipment user is crane-to-building tolerances. According to IS 3177 guidelines, there must be no stationary object in the path of the moving systems. Thus, your hoist and crane should have no effect on the building structure.
It is better to install the crane system in a place where vertical (like pipes and lights) and horizontal objects will cause no interference.
Some cranes span less than 15 meters, and for them, rail-to-rail elevation should not be over 4. Conversely, bigger cranes with a span of 15 – 30 meter must have elevation of not more than 6 mm. While the crane span is above 30 meters, this elevation is 10 mm.
Runway condition and straightness
You have to check out the space present between tracks, as it should be 1.5 mm based on IS 3177 standards. Some professionals think that there must be a bigger wheel with a heavier rail. However, regardless of the size of a track, 1.5 mm is the perfect standard.
The crane runway must match the overall system structure. As the runway works like a foundation, it must not be outdated and corroded. The damaged and defective runway may cause other issues. Moreover, crane overload and failure other some other factors resulting in runway dislocation.
Lastly, we need to say that you must hire qualified professionals to inspect your cranes and their runways. They use the modern laser and transit system to analyze runways. You can operate your cranes properly with their regular inspections.