Mechanical, pneumatic and hydraulic. Those are the three types of tool clamping systems available to any press brake owner. Each has its pros and cons, but one provides several benefits that the others can’t touch.
Dave Bishop is the business development manager for the Western region at press brake tooling provider Wila USA. He’s quick to point out that Wila offers each style of clamping technology, and that this isn’t a sales pitch for one over the other. He does have a favorite, however, and explains why pneumatic has become the preferred technology in Europe and some Asian countries and is quickly gaining steam in North America.
Requiring a hand
Let’s start with that old standby, mechanical clamping systems. They’ve been around for as long as the press brake itself and are standard on most machines. Basic clamping systems rely on a series of manually operated setscrews to hold punches and dies in place, although some quick-change systems have a lever that clamps a series of tooling sections in one motion.
Both are easy to use and the most inexpensive of the three options, but even the quick-change option is slower than the alternatives. Nor does manual clamping of any kind support automation, which is quickly becoming a differentiator for shops aiming for maximum competitiveness.
For shops producing high part volumes where changeover is rare or budgets are tight, mechanical clamping systems are often the way to go. They do, however, require more skill level than hydraulic and pneumatic clamping systems, an important consideration given today’s labor shortage.
Hydraulic clamping seems like a no-brainer, and in many applications, it is. As with press brakes, hydraulic clamping systems provide lots of power in a small package, far more so than pneumatic clamping systems. And although the early iterations of some hydraulic clamping may have earned the operator a bloody nose due to ruptured bladders and subsequently oily floors, newer hydraulic systems are typically leak-free and quite dependable.
They do, however, require oil to operate. For many shops, this is no big deal, and any concerns over sustainability and disposal of used hydraulic fluids come secondary to getting parts out the door.
With these shops in mind, Wila supports hydraulic clamping systems. Install a powerpack and a little plumbing, fill the reservoir with a gallon of fluid (less than most systems), and get bending. No problem.
But as noted, there has been a massive shift in the European and Japanese markets in recent years as these countries tighten their environmental regulations and embrace the concept of sustainability. That shift is toward pneumatic clamping, and it’s making its way to North America.
A look at air
There are some excellent reasons for pneumatic clamping. The most obvious is that there’s no oil. This makes maintenance a bit easier and installation slightly less expensive and more hassle-free. And even though leaky hydraulic clamping systems are rare, you know there will never be a need for Floor-Dry with pneumatic clamping systems.
Learn about the Wila AirPower pneumatic clamping system to speed up operations and maximize productivity.
But hold on, you’re thinking, hydraulics are more powerful. In fact, my press brake is hydraulic, so why wouldn’t I want the clamping to be hydraulic, as well? It’s a fair question, but it’s not comparing apples to apples. Driving the huge cylinders on most press brakes requires far more force than actuating a small mechanism that clamps and unclamps the tooling attached to the ram and bolster. Hydraulic is overkill in this instance. It’s also slower than pneumatic, although not by a whole lot.
Here comes the second argument: compressed air is expensive, right? Once again, if the actuation cylinders were large, this might be a valid complaint. As it is, though, only a small amount of compressed air is needed to actuate Wila’s AirPower clamping system.
Pick the best
So, which is the right choice? As suggested earlier, it depends on production quantities, setup frequency, operator skill level and available budget. And here again, Wila supports all of the available options. What’s most important is to select a clamping system that works for your shop and will make your bending operations as efficient as possible.
Lastly, there is significant merit in the stance taken by your overseas competitors. Most will tell you that Wila’s AirPower system costs less to operate per year. It’s also friendlier to operators and maintenance technicians alike, not to mention the planet. And for shops that want to automate their press brake operations and hopefully pick up a shift or two of unattended operation, pneumatic clamping is – in most cases – the first choice.
Whether your press brake was built in the Clinton years or will arrive after the holidays, it might be time for a breath of fresh air.