With some exceptions, almost every industrial processor who handles coiled materials will have to address slack loops at some point.
Uncoiling machines, e.g., payout reels, can’t typically keep up with the speed the feeder will move material forward. A slack loop provides a reservoir of that material, which ensures there is always enough to progress the material forward as needed without slipping.
Slack loops come in three varieties–horizontal/traditional, overhead and paddle. The processor’s material and process are the two main driving factors behind which loop is right for a particular line.
Let’s take a closer look at the three styles.
Horizontal Slack Loops
This is the traditional and most common slack loop. It’s very versatile and supports high-speed feeding and longer progressions. It’s also a good fit for thicker materials, as those materials require more space to get into a loop.
Speaking of space, that is one spot where the traditional loop lacks. Horizontal loops can require a lot of space to ensure the proper loop. For some organizations, this may require a looping pit–a depression in the floor that allows the machines to be closer together, while also providing the necessary space to the required loop.
While horizontal loops might be traditional and very common, they’re not necessarily the safest option. In fact, with a long length of freely hanging material that rises and falls as the material is fed, and possibly a deep pit in the floor as well, this setup provides a variety of hazards and opportunities for injury. Organizations can counter those issues, though, with everything from fencing to keep team members out of the danger zone to threading tables, which are used in conjunction with pits to raise the material to the level of the next machine. This allows team members to thread the material into the feeder without having to lean over the pit. When the material is threaded, the tables are let down to create the loop.
In a paddle loop, the reservoir of material isn’t between machines–it’s stored on the payout reel itself. The loops hang on the payout reel and the feed draws from those.
Paddle loops are often ideal for organizations looking to save space, as long as the process doesn’t include surface-sensitive materials, that is. The paddle loop setup allows organizations to place their uncoiling machine and the next in the line closer together. But, due to the way the loops hang, the material rubs against itself as it is fed out. This could mar surface-sensitive materials, such as painted metals.
While they’re great for saving space, paddle loops shouldn’t be the top choice for those with a fast-running line–it can be really hard to keep the loop properly supplied if the line is moving fast.
As the name implies, overhead loops are located above the machine, rather than at machine- or below-machine level.
Overhead loops are another great way to save floor space, or if the organization just isn’t interested in digging a looping pit. At EnSight, we often see the overhead loop start at the coil cradle and then go up through an overhead chute that guides it to the next machine.
This setup is only feasible for thicker, heavier material, though. Light, thin materials will collapse on themselves in an overhead loop.
Industrial processors who run a high-speed line but don’t want to sacrifice space for a horizontal loop can benefit from the overhead loop design.
At EnSight Solutions, our sales consultants have helped numerous organizations determine the proper slack loop for their line. We start the process by learning everything we can about your materials, your line and your facility. While the materials themselves often dictate which loop is best, we work with organizations who also want to reduce their line’s footprint. We can also recommend and integrate safety equipment and measures to help protect your team.
In regard to slack loop size, there is a standard formula that many companies use. Our team uses the formula more as a starting point, as it doesn’t take into account a variety of factors, including material width and hardness and floor space. Therefore, the loop our team will help you integrate will meet your needs first and foremost.
Ready to learn more? Contact our industrial processing specialists now to discover how EnSight Solutions can help you optimize line performance, increase efficiency and keep team members safe!