By teaming up with a company in Thailand for a new shuttle machine, Graham Engineering Corp. was able to develop two new blow molding machines at the same time - the SBG shuttle and a 12-station Mini wheel, company officials said.
Sabmann Blasformtechnik of Petchaburi, Thailand, did detailed engineering work to develop the base frame and clamp assembly for the SBG 700 D shuttle machine, using Graham's extrusion and process-control technology. Graham Engineering did the machine specifications and oversaw the project, said Dave Yenor, vice president of global business development.
``In an increasingly competitive global environment, this partnership makes great sense for both parties,'' Yenor said.
Graham Engineering molded parts on both the SBG and the Mini wheel during a five-day open house, held the week of Feb. 25 at its headquarters in York. About 40 visitors came, including people from Europe, Asia and Australia, said Brian Dowler, director of market development. The international guests were especially interested in the Mini wheel, a lower-volume, compact wheel that is designed to fit into a shipping container, he said.
Wheel keeps turning
The company introduced the both the small wheel and the new shuttle press last fall, at the K show in Dusseldorf, Germany. But Graham only took the wheel portion of the Mini wheel to K. The February open house marked the first time it was run at a public event.
In York, the Mini wheel turned out 55-60 wide-mouth fruit jars a minute, from clarified polypropylene. Graham designed the lightweight bottles - each 24-ounce bottle weighs just 38 grams - at its laboratory in York, working with a food packer. The machinery maker has added several pieces of new testing equipment, including a new microscope that measures the thickness of each layer of a multilayer bottle.
To make the six-layer fruit jars, five extruders pump material through a single die head to make a parison that gets blown upward. The wheel carries 12 molds, which clamp shut around the parison.
Graham is marketing the Mini wheel as a good machine for coextruded packaging for oxygen-sensitive food products, such as flavored milk, organic drinks, coffees, teas, drinkable yogurt, fruit juice and packaged fruit, plus ketchup and jellies.
Yenor said wheel technology has some key advantages over a shuttle for coextruded containers. Wheels are energy efficient, he said, because electric power runs the wheel, and the only hydraulic power is for parison programming.
But the biggest benefits are simplicity, precision and repeatability, thanks to the mechanical, cam-action movements.
``The parison length is exactly the same every time, because the molds mechanically close in the same position every time. And you've captured it at both ends, so you don't have any parison swing [like a shuttle]. You only have one parison to control, whereas on a shuttle machine, for similar output you'd have multiple parisons that are free hanging,'' Yenor said.
After molding, scrap trimming from the tail and flash gets ground up and automatically fed back into the process, to become the regrind layer in new bottles. As the clamp opens, arms revolve to pick out each bottle, placing it on a conveyor.
Each mold weighs about 20 pounds. Each comes with a built-in handle, for easy changeovers.
To get production levels like the Mini wheel on a shuttle machine, a six-parison, double-sided shuttle is required.
Graham employees build the Mini wheel in York.
Collaborating with Sabmann Blasformtechnik was the only way that Graham Engineering was able to create two new machines, simultaneously, in time for K 2007, Yenor said. Behind him, the SBG 700 D was extrusion blow molding 2-liter, polyethylene handled bottles at a rate of 54 per minute.
The SBG is Graham's next-generation shuttle. Molds can be interchanged from the previous Graham shuttle, the HLD 700. The 700 refers to the distance of the carriage stroke - 700 millimeters.
Graham Engineering had retained the HLD 700 design when it sold the Hesta product line, and closed its German factory, in 2006.
``The clamp has the same width, so the same head centers from one machine to the other,'' Yenor said. ``But the SBG 700 machine has an expanded capability over the HLD in terms of clamp tonnage and opening stroke, for larger containers.''
The SBG 700 has 25 metric tons of clamping force. At the open house, a four-parison extrusion head shuttled back and forth between two clamping mechanisms.
Sabmann ships the frame and clamp as a subassembly from Thailand to York, where Graham technicians add the extruders and process controls, and do the final assembly.
Graham Engineering provides marketing, commissioning and service and support. Machines delivered outside North American will be delivered with Willi Muller die heads and qualified at Sabmann's facility in Thailand, by Graham personnel.
Yenor said the company may decide to expand to add more sizes to the SBG line, probably with smaller sizes.
Sourcing major components from Thailand helps Graham Engineering compete in the price-sensitive and competitive market for shuttle blow molders. But Yenor said the main advantage of using Sabmann was that it allowed simultaneous engineering.
``Our intention wasn't to be a down and dirty machine,'' he said.
Both the SBG 700 shuttle and the Mini wheel use KnÃ¶dler gearboxes for their extruders.
In fact, Graham has standardized motors from K. & A. KnÃ¶dler GmbH of Ostfildern, Germany. Under the deal, Graham Engineering now is the exclusive North American company to service KnÃ¶dler gearboxes for all industries, even outside of plastics machinery.