Ask a vacuum conveyor vendor what's new and the answer is likely to be both "not much" and "everything." After all, vacuum technology has changed little over the past decade but each conveying project presents a unique combination of processing issues, usually requiring some customization.
"There are not a lot of new things about vacuum conveying, but there are new applications every day," notes Doan Pendleton, vice president of marketing and sales for Vac-U-Max, Belleville, N.J.
"One of our strengths is that we have a standard line of equipment and also a custom metal shop. If you have an application where you have to discharge to a mixing tank next to a wall, we can take our standard vacuum receiver and reengineer it so it fits into that space," he says.
Piab, Hingham, Mass., boasts that its highly modular equipment provides flexibility. "We can customize anything based on a mix-and-match approach," explains Brian Wilson, who handles technical sales and support for the company's Material Handling Group. The firm makes a single vacuum pump housing but can alter vacuum capacity simply by adjusting the number of air ejector cartridges. "If an application changes and they need more capacity, we can swap out components and add air ejector cartridges, filters or a module for fluidization," he says.
"Customization is our forte. We're not trying to shove a single design or approach down a customer's throat," notes Ed Heller, president of Industrial Equipment & Design Co. (IEDCO), Turnersville, N.J.
Customer demands continue to evolve. Chemical manufacturers want new vacuum systems to increase throughput, protect worker health, and improve plant safety and efficiency. Yet, because their staffs are lean and overloaded with projects, they expect a lot more from vendors. Instead of looking for vacuum conveyors and receivers, facility managers want complete systems that they can plug into plants and forget about.
This trend has been apparent for 10 or 15 years, but intensified since the recession in 2008. "Many customers rely on us far more than they had for preventative maintenance and also for advice on what spare parts they need to carry to keep their plant running optimally," says Nick Hayes, president of Volkmann, Hainesport, N.J. Some companies, such as Hapman, Kalamazoo, Mich., also offer formal managed maintenance plans for their equipment.
FILLING A VOID
Plants opt for vacuum systems where screw conveyors, which are simpler and less expensive, simply won't work. "The number one thing people look at first is a screw conveyor," says Steve Grant, Hapman product manager. "But maybe the vertical distance is too high, or you have to work around existing equipment, or maybe you need to go around a couple of bends or through a wall… Or if you're involved in batching operations, it's more ergonomic to put a vacuum wand in a drum and empty it out than have someone carry that drum to the top of a hopper," he adds.
Unlike screw systems, vacuum conveyors can curve around reactors and deliver particles to an upper mezzanine with a 90° bend. While not as low-cost as screw conveyors, they are relatively inexpensive and require little maintenance. Vacuum lines even purge themselves (with a vacuum, of course) when switching between products. They also simplify dust control, because any leak will suck in air rather than blow out powders.