New Player, Familiar Name In Downstream Extrusion Equipment
Close Up: NPE2012 News Wrap-Up
Bessemer Series debuts at NPE2012.
There’s a new supplier of downstream extrusion equipment for pipe, profiles, and tubing—one whose management roots in this particular slice of the machinery business aren’t really new at all. And with that comes a fresh, processor-driven point of view in designing equipment aimed at solving real needs of users of this machinery.
Baltimore-based Novatec Inc. rolled out the Bessemer Series of cooling tanks, pullers and cutters at NPE2012 last month in Orlando, Fla. At first blush, the new line may seem like an odd fit for a company whose worldwide reputation is in drying and materials-conveying systems. But look a bit closer: A year in the making, Novatec’s entry into extrusion downstream equipment is the brainchild of Conrad Bessemer, its president and CEO. Before coming to Novatec in May 2006, Bessemer worked for a handful of downstream-extrusion suppliers, including Versa Machinery, G.F. Goodman & Son, and Conair. While at Conair, Bessemer led the 1988 acquisition of Gatto Machinery, which was the predominant manufacturer of downstream extrusion pullers, cutters, and tanks.
“This equipment has not changed dramatically in decades,” Bessemer says. “Certainly there have been incremental improvements, but processors today are essentially cooling, pulling, and cutting product the same way they have for years. There is still too much ‘art’ involved, with operators turning knobs, and not enough science. What we are striving for is to offer equipment that helps make the process more repeatable and recipe driven.”
Nowhere is this effort more evident than in the area of controls, Bessemer notes. “Even today, in what has become a ‘wireless’ world, if an operator is at the cutter making a change, or at the puller adjusting line speed, he has to make a mad dash of 100 ft or more to the cooling tanks to make the adjustment there,” he says.
The overriding philosophy behind the Bessemer Series is to treat cooling tanks, pullers, and cutters as a system, as opposed to discrete components operating independently. To that end, each machine is equipped with a Siemens PLC-based, touchscreen controller, all of which are linked—something Novatec maintains is an industry first. This allows, for instance, cutter controls to be accessed from the tank, or the temperature of the water in the tank to be manipulated from the puller. The system can also be operated wirelessly. And it can be networked with sister company Maguire Products’ LineMaster gravimetric control system for complete extrusion line control.
“Recipe-driven process setups drive repeatability and can be structured for all products,” Bessemer explains. “This lessens the need for ‘expert’ knowledge on the part of the operator, as the menus are coordinated between smart, connected downstream components. And since the equipment is truly a system instead of discrete components, this means less tinkering and tweaking by operators.”
These and other enhancements were initiated based on input from a beta group of profile processors. “From the start we tapped into end users to find out what they always wanted and never had,” Bessemer says. “What are their problems, their pain points? What can we do to improve control and accuracy?
“The technology regarding the software for this equipment is exactly what we have already done for our core business, with touchscreens, intuitive software, and process-driven recipes,” Bessemer states. “We’ve doubled our dryer market share as a result of that approach and we expect the same results here.”
At NPE, Novatec introduced its first downstream offerings. Its High-Intensity Spray Tank features all-stainless-steel components and construction. It offers pneumatically activated top door lids that can be operated independently; fully automated, three-axis tank positioning; quick height adjustment of roller position; SPC data for machine capability and current/historical data; remote monitoring of supply and return water temperature; remote monitoring of extrudate exit temperature; remote monitoring and control of vacuum; and closed-loop control of water flow rate and temperature. Flow rate and temperature are independently regulated. Each of the six spray bars can also be controlled individually. Everything is recipe-driven
Working with consultant Wesley Sipe, Novatec developed a cooling simulation program that will enable processors to take the guesswork out of cooling-length requirements across a range of 20 common profile shapes and six commonly used profile materials. Users plug in the profile shape and material, and the computer simulates the cooling time needed by calculating the convection heat-transfer coefficient from the profile into the coolant, while taking into account how the mechanical properties of the profile are impacted by specific temperatures.
A key feature of Novatec’s new pullers is load-cell technology that monitors and controls belt-compression forces, taking the operator element out of the equation. The unit shown at NPE offers 4 x 30 in. traction and recipe management for consistent and repeatable setups. Initial setup and steady-state operating speed can be programmed for consistency. Dual servo drives offer five times the accuracy of variable-frequency drives while eliminating relative slip between the belts.
Motor-driven belt-height control is said to ensure repeatability. The puller also offers automatic pneumatic belt tensioning and two boom-adjustment modes (manual/automatic). All features are recipe driven.
On display at NPE was a 3-in. on-demand Continuous Extrusion Cutter (a 5-in. size is also available). The unit offers a high-torque flywheel for variable speed and continuous cutting.The temperature of cut pieces is sampled and displayed for improved cut quality consistency.
Setup is eased because the cutter is programmed to consider expected line speed to determine other settings. The cutter has one-step “start to save” that sets totalizing counters to zero. True cut-length setting matches part length. “Scrap/setup” cuts to convenient granulator length.
Bessemer said Novatec will take an incremental approach to filling out the product line. In the works is a saw-type cutter that will be designed to minimize dust. He expects Novatec to have a considerable edge in delivery times as a result of the companywide philosophy of maintaining a robust inventory of modular products and all components. “We’re in this business for keeps, especially given the huge response we received at NPE,” Bessemer says. “Our target is to be the number one supplier or a strong number two in five years.”
The company has hired Bob Butts as v.p. and general manager of extrusion. Trevor Bludis, who has worked as a designer for defense contractors and also in the power-tool industry, has joined Novatec as design engineer for the puller and cutter line. Novatec has also doubled the size of its software group over the past year.
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