Industrial technology may advance at an alarming speed, yet that ever-present heavy-lifter of the mechanical world - the Slip Ring - remains a commonplace component in more than its fair share of industrial devices. From the manufacturing industry, to more hazardous environments like marine and forestry, through to aiding in the uptake in clean energy through wind power and turbines, Slip Rings are ubiquitous: they get the job done, and they do it well.
Slip Rings are, also, notorious for failure. Granted, all equipment is bound to fail at some stage, it’s just a matter of when, and given the operating conditions most Slip Rings find themselves exposed to, they malfunction more than most.
Time is money in any environment though, and Slip Ring repairs and maintenance are guilty of costing businesses both. To put it another way, if a Slip Ring fails, the equipment stops working, and usually takes the entire operation with it. New technologies like Wireless Slip Rings are starting to offer a viable alternative to traditional slip rings, and ushering in reduced maintenance costs and upkeep concerns with them, yet most of today’s equipment is still stuck operating on aged Slip Ring technology.
While replacing existing Slip Ring equipment with newer technology isn’t always viable, at least in the short-term, there are at the very least a few simple, common sense ways engineers and businesses alike can cut down on the time and money they spend dealing with Slip Ring failures and ensure they’re running to the best of their ability.
Modern Slip Rings are renowned for their modular design, which offers flexibility and a compact size and allows the end-user complete freedom to combine the power and signal channels in a way that best suits their application’s individual requirements. However this modularity is both a blessing and a curse, in that configuration errors are that much more common.
To help eliminate configuration errors, consider:
Proper orientation matters! Even experienced engineers can be guilty of configuring a Slip Ring without any regard given to the final mounting orientation of the device, or how it will be installed on the machine. Slip Rings aren’t one-size-fits-all equipment. What works for one device might not work for another, and different mounting orientations require different Slip Ring configurations.
A Slip Ring’s signal channels are far more susceptible to contamination from dust and other particulate matter than the load channels. It’s this dust that’s more often than not responsible for degrading the signal quality, and shortening the regular maintenance intervals - and even the lifecycle - of the Slip Ring itself.
During the configuration process, engineers should ensure that the signal channels are set above other modules, such as the labyrinth seals and those used for power. By correctly configuring the signal channels so that they sit at the top of the Slip Ring, gravity will be able to work its magic and minimise the amount of dust that falls onto the signal channel and, in turn, reduce the damage done and the maintenance required.
Any equipment, industrial or otherwise, requires regular maintenance, but Slip Rings are often trickier than most. The key concerns here are threefold:
Poor maintenance routines enacted by the end user.
Missed maintenance or improper maintenance techniques.
Most commonly, specific Slip Ring designs being inherently difficult to maintain.
To help address these concerns, consider:
All Slip Rings require regular, routine maintenance, but not all Slip Ring designs are necessarily great at facilitating it. To avoid this, look for Slip Ring designs that provide ready and easy access to both the power and signal contacts, without requiring manual - and repeated - disassembly of the Slip Ring itself.
Not all working environments are created equal. A factory, for example, won’t put equipment through anywhere near as much stress as more hazardous environments such as those the marine or forestry industry face on a daily basis.
For this reason, Slip Ring maintenance should start on the drawing board, not the factory floor. Pre-planning and decision making during the design process can save money and downtime in the long run, so consider the operating conditions and the environment when you’re setting expectations and timelines for Slip Ring maintenance. Will the device be operating in a wet environment? Hazardous? Dusty or dirty? These environmental factors will negatively affect the Slip Ring, and speed up maintenance intervals, so consider this closely.
Set regular, common-sense maintenance intervals and stick to them. Generally speaking, the first Slip Ring maintenance should be carried out at 50 million revolutions or after one year of continued operation. Whichever comes first. From there, all subsequent maintenance intervals should be scheduled yearly, or every 100 million revolutions.
Note that these are general maintenance intervals and, as discussed earlier, should be adjusted to suit the individual operating environment and conditions of the Slip Ring itself. If the equipment - and, in turn, the Slip Ring - is operating at higher rotational speeds, within contaminated environments, or at elevated temperatures then these aggressive conditions should be met with an equally aggressive maintenance regime.
The maintenance routine itself varies depending on the device in question, the environment in which it operates, and any significant differences that relate to your individual situation. Generally speaking, most Slip Rings use a vacuum or high-pressure air hose to remove any dust that has accumulated on the Slip Ring load and signal contacts.
The specific maintenance best practices for any given slip ring are usually provided by the manufacturer, and you should talk with them extensively both pre-and-post production and installation to ensure you have all the information required to ensure that your slip ring achieves its maximum life expectancy and meets its full operating potential without costing you your equipment, your time, or your money!