Many converting machines have the potential to make real-time corrections in the manufacturing process — so why don’t more companies take advantage of the automation at their fingertips?
Confucius said, “The way out is through the door. Why is it that no one will use this method?”
There are many interpretations on the exact meaning of this phrase, and while we don’t think the ancient philosopher was referring to converting systems, we find it apropos to the topic of automation and closed-loop manufacturing.
Closed-loop manufacturing can provide real-time corrections for a variety of converting processes, including rotary die-cutting, laser die-cutting, coating and more. So why don’t more companies use this method?
How are Real-Time Corrections Made in Closed-Loop Manufacturing?
Closed-loop manufacturing has many facets. In this post, we’d like to focus strictly on real-time registration corrections. This can be done using sensors or a vision inspection system.
Registration or re-registration is a process where multiple materials, parts, layers, print or die cuts are placed in a specific orientation with each other using the timing and/or gearing of the rollers.
On older, outdated converting presses, constant operator attention and manual adjustments are required to make good products. The machine must run at a speed where the operator can physically see a problem and react, manually making the adjustment.
Automating this process is more efficient, allows for faster speeds and is usually essential in cases of extremely tight tolerances.
On modern converting systems, cameras or sensors and servo motor control make registration an automated process. The sensor or camera sends a trigger signal back to the converting machine’s control system, which automatically makes an adjustment or correction to the registration. Servo control and split-second feedback allow for quick and precise adjustments automatically.
For operators trained on older, outdated converting presses, this is a departure from current processes, but can result in improved overall efficiency. “Automation can reduce your scrap rate,” said Ryan Herman of Delta ModTech. “You’re not relying on an operator to notice it’s out of spec.”
Why Don’t More Companies Automate a Closed-Loop System?
If the concept and benefits of a closed-loop manufacturing sounds so good, why isn’t it being implemented by more converters? There are a number of reasons — some valid business decisions, some human shortcomings.
1. New Product Set-up Time
We all know changeover time is critical. Cutting corners on proper set-up or mechanical band-aids to just “get it out the door” will, in-turn, slow your manufacturing time.
For example, an experienced operator who is new to automated registration may set a job up and run it using manual registration adjustment. Why?
Likely he is not prepared with the correct tools, training or documented machine settings. He may also know that he can just run it and make the adjustments on the fly, even though he’ll be running at a slower speed with more room for error.
What experienced operators fail to see is that not only does proper set-up from the start waste less material and allow for higher productions speeds, it will also make the next run of that product or similar product faster.
Need to improve your set-up times? Check out our previous post on quick changeover for some guidelines.
2. May Have an Outdated Machine
While it may sound obvious, you may not have the capability to change registration on the fly because your machine is simply too old.
There are still many manufacturers using old and outdated equipment to “get the job done.” The ability to retrofit newer technology is an option, but many times it will result in more long-term costs than upgrading the entire line.
3. Not Aware of the Technology
In many operations, closed-loop capability exists on the machinery, but the management team simply isn’t aware of it. Typically, management gets the sales pitch on what a new machine can do, and then they drop it in the operator’s lap.
The operator may have on-the-job experience, but not on the new equipment under his control. Yes, he may be able to produce the products, but sometimes pride gets in the way of getting the most out of a machine.
Manufacturing environments are intense. High expectations of throughput may overshadow operator training and advancement. Unless trained and instructed to do so, lead operators will simply revert back to their old ways of doing things instead of using the new automation.
What Does it Take to Implement a Closed-Loop System?
You’ve reviewed the reasons why converters don’t use a closed-loop system. What can you do to determine if you’re a good candidate for the process?
1. Analyze Your Costs
It all starts with the numbers. Take into account the cost of the system, the impact of changeover time, and the long-term consequences of a mistake.
Medical device manufacturers are well-aware of these numbers. For others, you may have analyzed these areas in broad strokes, but they require a more thorough review.
2. Re-Program the System
Work with a provider to adjust your machine’s control systems. This is usually beyond the realm of the operator; you’ll have to work with the machine manufacturer and/or system provider.
3. Adjust Your Process and Retrain the Team
The goal of this post is not to downsize your operator force. It’s to make your overall system more efficient and improve product quality and throughput.
Moving to a closed-loop system will require an overhaul of your current process, including a revision of how you’re using your operators. As the system is adjusted, your operators’ roles will be redefined. They’ll need training on how to work with their new capabilities.
What’s the Impact?
Results will vary, but as Ryan Herman said, “It’s common to get 50% decrease in standard deviations when you add automation with the newest monitoring.”
That’s a major impact on your system. Beyond the present-day differences, considering the value of a closed-loop system could pay huge dividends down the road. Tolerances will continue to grow tighter, margins will continue to shrink. You’ll always be required to find ways to produce more with less scrap.
Most importantly, your machine should not be the bottleneck of your process. Technology has advanced enough that the finished parts and materials should be piling up behind your machine. Your team should not be tapping their feet, waiting for the product to be done.
The door may be open for you, right now. Are you ready to walk through it?