- March 29, 2019
Push your punch press technology to its full potential
The turret punch press has come a long way from the days of mechanical flywheels and hydraulic driven machines. Today’s servo driven punch press machines are more energy efficient, and the automation and software packages designed for these machines have transformed this processing technology into a true multi-tool. Do shops realize their full potential? Many suppliers and manufacturers of punch press machines say, no.
“These machines have become more than a single task machine,” says Lutz Ehrlich, punching and automation product manager for Prima Power. “In the beginning, the punching machine punched holes. Today, we can form, contour, mark, etc. With the capabilities of new technologies, these machines are much more versatile then they were 20 years ago.”
While these machines are now more flexible and adaptable to a multitude of processes, the biggest challenge suppliers are faced with is reeducating the customers. “A lot of times, companies are happy when they get a process done, but they’re not taking the time to advance themselves. That’s the trick. People need to learn how to use these machines and understand how they can make their processes more sustainable,” adds Ehrlich.
All fabrication shops want to reduce the price of their parts, and with a lack of skilled workers coming down the pipeline, many are starting to consider automation options. And the different types of tooling for the turret punch press are not only saving customers money and time, but also eliminating secondary processes.
“The turret punch press is still in demand for forming operations. And whether you have a punch, a laser or bending cell, we are seeing customers looking at automating their punching processes,” says Craig Amedeo, punch product manager for Amada. “If you’re running a standalone machine that’s not automated, the green light time is on an average 30 to 35 per cent when the machine is actually making parts. When you move to an automated machine, that green light time is increased up to 80 to 85 per cent, which is increasing throughput and reducing cost per part.”
Dan Caprio, punch press product manager for LVD Strippit, says many customers are using punch presses well for what they’re producing, but they’re not looking outside of the box at what features those machines are capable of to expand their business. “The wheel tools, forming tools and bending tools are more exact and precise with the monitoring equipment that’s now offered. These machines can do so much more…they can tap, bend, down form, up form, coin.”
Tapping, for example, has become very popular. “We’re doing a lot of that with punch presses now. There’s no room for error, the end quality is there, and you don’t have to send the part to a tapping station,” says Amedeo.
Obviously, the least amount of times a part is touched, the less the cost of that part will be in the long run, and if shops can eliminate secondary processes the overall throughput becomes much more efficient. “I was in a facility the other day and a customer was grinding burrs off of a sheet. I said ‘we have a tool for that.’ And it’s much faster than a guy with a file,” says Roger Michaud, TRUMPF’s product manager for TruPunch and TruMatic machines. “And for customers that need to mark parts, we can create a dot matrix to do an ink mark on parts that can be wiped off. We also have a multi-tool with numbering that can engrave the marking and powder coat over it. So, if a customer wants to put a serial number on the part, they can do that too and it’s permanent.”
Punch presses are also capable of performing long progressive bends without damaging or scratching pre-painted materials.
What’s driving all of these flexible possibilities is the automation and software designed to optimize such processes. In the past, programmers really needed a cheat sheet to know what tools were in the turret. Today’s machines have automated tool changers and monitoring systems for quality control and preventative maintenance.
LVD Strippit offers a wide range of punching equipment, from entry level to fully automated systems. Caprio says that LVD’s PX series is a high end machine with 20 indexable tool stations. It can bend up to three inches and process those long progressive bends.
LVD Strippit has worked with companies to come up with solutions for progressive bending. “Years ago, everything was on a solid turret and you did what you had to and repainted the material or didn’t use painted material,” says Caprio. “Our PX machine has three inches of feed clearance, and along with the software, we were able to come up with a solution that allows you to take the punches and lower the die out in a way so that the material is not scratched. Using automation to address progressive bends saved one company we work with about three shifts a week.”
TRUMPF’s TruPunch 5000 series is a production level machine that allows the integration of automation and has 25 tons of punching force. It can process ¼ inch materials and features what TRUMPF calls an active die that reduces scratching.
With the automation and software combined, operators can easily adjust the system on the fly. “And our machines are smart enough to know what tools are there, what tools to change and when to change them,” says Michaud. “If there’s anything the operator missed, the machine will tell you the wrong tool is loaded and ask you to swap it out.”
“A lot of things have changed with new developments in software, yet some elements have been kept from the early days,” says Ehrlich. “For example, they have a very flexible, adaptable turret to ensure you’re not constrained with manufacturing. You can add other index stations or forming stations. And you can change your turret layout at any given time. You also have the capacity, depending on the machine model and configuration, to have up to 300 tools in an active stage, meaning you don’t need a passive tool changer to bring the tool into the active cell.”
Software designed for today’s automated machines has become easier to use and more intuitive. But it is essential that designers and programmers understand the technology available on the shop floor, including the advantages and disadvantages caused by design, and there needs to be a clear communication between the operator and the programmers.
“With our software today, you can batch nest,” says Amedeo. “Again, efficiency, time is money and batch processing from a software standpoint is very important. Built into the software, there are many variables that send alarms if, for example, you might try to bend ¼ inch material in a 6 mm V die. Guess what? You can’t. Or if you’re trying to get an .008 mm inside radius on 10 gauge. That’s going to be difficult to do without blowing the tool up or breaking the die. Engineers may not realize they can’t do a tight radius on thicker material. Our software is stopping them from trying to design something that’s not “manufacturable.”
If shops want to take their punching process to the next level, they can add automated loading, offloading and part picking systems.
“Sorting raw material and unloading finished parts is one of the biggest advantages of this automation,” says Michaud. “The nice thing about our punch machines is that they can actually sort parts. We can tell it what part we want to go down a chute, what part to leave in the nest, and what parts need to be picked. That reduces your workforce as far as these types of tedious jobs.”
Automating loading and unloading processes also remedies micro-tabbing in a nest of parts. “Certain parts are mirror images with a left and a right,” says Amedeo. “So rather than shaking them out of a sheet and the operator putting them in a bin, Amada offers a part picking system that will remove the parts and stack them in an organized manner and store them in a single or multi-shelf tower. So when they go to the next station to bend it, for example, the operator will have the right part or the right side of the part. If a customer doesn’t want to store parts in towers, we have a secondary output conveyor station that will take the parts to the next process.”
Suppliers say interest is growing for fiber laser punching combination machines.
“Fiber laser punch machines can give customers versatility and unlimited tooling. If you have a laser, you don’t have to buy a special radius tool for a special punch. You can contour with a laser cut,” says Amedeo.
TRUMPF’s TruMatic 1000 is now the flagship machine in its punching group, which features the company's TruDisc laser technology.
“The ramp up in the past year has been twice what we had in the past,” says Michaud. “Even if you start with a TruPunch, it can be built into a TruMatic if you want.”
Caprio agrees that there has been a steady increase in the combination market. “It’s still basically a punching machine. The laser is more of an asset to complement the machine. For companies that do forming, coining and stamping, for example, they need the ability to form, but they might have parts that have a lot of contours and this is where the laser comes in and really reduces their tool costs.”
One thing that remains the same with punching technology is that maintenance is crucial. “The tooling and tools required should be kept in like-new condition to achieve effective and sustainable goals,” says Ehrlich. “24/7 doesn’t work. [Shops] should take one shift a week for operators to clean, wipe, inspect and repair the machine. These hours can also be used to review the challenges of the process. There are some very high benefits to that.”
According to Ehrlich, it’s about educating operators on how to maintain the tools and knowing what the proper parameters are for the tools to be efficient. Many OEMs have a tooling library with history monitoring of tools and how many hits can be performed before you need to inspect the tool. “This should be more than a monitoring tool. It should be an active way of sharing critical tooling maintenance information within the team, especially if you have multiple shifts.”
The range of process possibilities on today’s punch press technology has transformed it into a multi-tool for metalworking operations. But for shops that haven’t looked at what’s become available or the advancements in the last 20 years, they’re not going to know they missed the boat until they go out to quote work, according to Caprio. “The most successful companies are the ones that have a plan to continually upgrade equipment. I think that’s true not only in our business, but any business.” SMT