When one of your overhead cranes just isn’t performing like it used to, you can face some tough decisions. Is it time to replace it? Should you invest in a new crane? Or is it merely time to modernize your crane?
Modernizing refers to enhancing and upgrading the original electrical and/or mechanical design of your crane and is often done to increase the efficiency of its operation and enhance its safety. Here are some of the benefits of overhead crane modernization:
- More cost effective than replacing an overhead crane
- Can extend the useful life of a crane
- Has the potential to reduce cycle times and increase productivity
- Leads to better energy efficiency
- Can better protect employees, loads, and other equipment
- Much shorter lead time for replacement parts
- Reduces the frequency of unscheduled shutdowns
- Can lead to more precise control of the crane
- Less wear and tear on the parts
Now let’s look at how you can upgrade your overhead crane.
Modernizing the Motor Controls
An excellent way to upgrade your overhead crane is to select a more modern control system. For example, for AC driven cranes, experts recommended upgrading to VFDs (Variable Frequency Drives), which provide highly tuned control of the AC motors driving your cranes — including trolleys, hoists, bridges, hooks and other below the hook devices. And they can be used for any type of crane application.
There are several benefits to variable frequency drives, including their ability to reduce the severity of severe impacts during starting and stopping, which in turn reduces the wear and tear on other components. Their more precise positioning and greater degree of control also enhance safety for workers and loads being transported. VFDs also require less maintenance and are extremely reliable, both of which reduce downtime and increase throughput.
Older DC cranes were usually designed to control speed using contactors that switch regenerative load currents over to resistor banks to dissipate energy. This approach, known as DCCP (DC Constant Potential), has some major issues, including the fact that the contactors and other components involved experience wear over time. This leads to extensive maintenance, especially when operating in a harsh environment.
When your DC motors are in good shape, adding a drop-in solid-state digital DC drive control is a great way to upgrade a DC-powered overhead crane. The addition of solid-state drive controls will enhance the performance of the crane, increase safety, and significantly reduce maintenance requirements. These drives also do an excellent job of conserving energy because they recover energy from the load and then return it to the DC power supply. Another option would be a DC digital static drive, which also serves as a drop-in replacement with similar benefits to a solid-state drive control. It offers extremely reliable performance when used with DC shunt-wound motors.
Installing New Motors
Over time, even the best quality electric motors will experience a change in their RPM. When you have two separate motors driving the bridge, a difference in RPMs is not a good thing. One side of the bridge will begin moving faster than the other, which leads to problems including alignment issues and uneven wear. An excellent investment in modernizing your crane may be to update the existing motors with new models that are more efficient, require less maintenance, and increase uptime.
Upgrading to Modern Crane Brake Systems
Another excellent way to modernize your overhead crane system is to upgrade the crane brakes, especially when combined with updated motor control systems (e.g., VFDs and solid-state DC drives). Modern brake designs often include features such as automatic adjustments that can compensate for brake lining wear and self-lubricating composite journal bearings, both of which reduce maintenance requirements and downtime.
There are also several different options available when installing new crane brakes. For example, drop-in brakes meet the dimensional requirements of existing brakes and are compatible with existing brake wheels. This option eliminates the cost of brake support modifications, usually costs less than traditional replacements, and provides excellent performance. Another possibility is foot pedal brake-by-wire systems (which provide the same feel as traditional hydraulic braking systems) with AC thrusters that require less maintenance and pose less of an environmental risk. If your crane has DC drum brakes, a good replacement would be AC thruster brakes, whose options include the ability to dial in the desired amount of stopping torque and automatic equalization/adjustment to reduce maintenance costs.
Adding a Remote-Control System
Remote control systems are another effective way to modernize your overhead crane. They can be used to replace either pendant pushbutton stations or fixed control stations and offer a host of benefits.
Overhead cranes can be safely operated out of harm’s way when using a remote-control system, which is much safer for the operator. There are no potentially hazardous hanging cords, the operator can control things from a vantage point of their choice, and the crane system is much easier to control. There are two options for crane remote control systems: RF (radio frequency) and infrared. Of these options, RF remote controls are preferred because they have a longer operating range and are not as sensitive to environmental conditions such as dust or bright light.
Implementing an Anti-Collision System
Anti-collision systems are used to slow down or stop cranes when they are moving toward another crane, structure, or object. Using either infrared sensors or lasers, they can detect and prevent potential collisions. Using an anti-collision system not only protects your employees but also protects loads and other equipment. It can also reduce maintenance and repair costs.
Installing New Crane Lights
It makes sense that crane lighting is an excellent way to increase the safety of your overhead crane. For example, it makes it easier for the operator to have a reliable frame of reference from the hook to the floor and makes it easier to precisely position the crane. When mounted appropriately, pedestrians can easily recognize the presence of a hook above them and see a safety boundary. Finally, they are easy to retrofit to most existing cranes.
If your crane already has lighting, it may be time to update to LED lighting. LED lighting systems are usually more compact, require less maintenance, are brighter at a lower energy cost, and are highly visible.
Some Signs It’s Time to Modernize
Let’s talk about some of the signs that it’s time for an upgrade to your cranes:
- Certain components are wearing out faster than they should
- You’re having too many near misses when it comes to safety
- The downtime for the cranes has been increasing
- It seems harder to position the loads accurately
- Some of the parts and components you need are becoming obsolete and harder to replace
- Inspections have been revealing issues such as safety problems or excessive wear
- Cycle times are getting longer
There are so many benefits to upgrading the overhead cranes in your facility, including enhanced safety and much better efficiency. If you can say “yes” to any of the signs listed above, it’s time to modernize. Our team of experts can advise you on what upgrades would benefit you the most so you can get the most out of your cranes.