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In Process 18599In Process 18599

November 3, 2005

5 Min Read
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Runner technology tees up for golf balls

The dimple patterns that make one brand of golf ball different from the next have designs that arise from a great deal of research, and the finicky golfers that favor specific brands pose formidable challenges to molders in this competitive market. Big Bend Machine and Tool Co. (Carrabelle, FL), recently began building four- and eight-cavity golf ball tooling with modular cores in conjunction with a material supplier for research purposes. It reported optimizing its molds with Beaumont Technologies? (Erie, PA) MeltFlipper product.

The balls, which are molded in a vertical press using parting-line injection into a four-cavity tool, use a mold that has a removable cartridge consisting of the cavity, support assembly with vacuum, ejector assembly, and a retractable pin mechanism. The MeltFlipper keeps material from freezing against one side of the cold runner channel for even fill. Meeting tolerances as tight as .0002 inch for dimple depths with .0002-inch cavity diameters, the MeltFlipper eliminated shear-induced material imbalances, and saved Big Bend the time and headaches of adjusting process parameters to deal with fill, pressure, and runner variations. For more information on Beaumont Technologies, visit www.meltflipper.com. To learn more about Big Bend Machine and Tool, go to www.bigbendmachine.com.


Extruder supplier helps bioresins grow

A biodegradable material derived primarily from corn starch and extruded into sheet for food packaging trays proved a challenge for Australian compounder Plantic Technologies Inc. Ltd. (Melbourne), but material formulation research with an extruder supplier would help overcome those hurdles and allow commercial production to ramp up.

In 2003 as Plantic began its search for twin-screw extruders, it started work with machinery supplier Entek, undertaking a number of trials on different material recipes to optimize production. Plantic eventually took delivery of two Entek twin-screw extruders for its Melbourne headquarters, and as interest from Europe for its corn-based packaging rollstock grows, it has ordered a third Entek extruder?a 103-mm twin-screw machine?that will ship by the end of 2005.

Plantic reportedly went through seven extrusion machinery suppliers before settling on Entek, choosing the company in large part due to collaborative material refinement work undertaken at Entek?s lab in Lebanon, OR, which actually received different raw materials in small batches from around the world as it tinkered with the resin. The material, dubbed Plantic, biodegrades in nature under the influence of microbes leaving only carbon dioxide and water. For more information on Entek, visit www.entek-mfg.com. To learn more about Plantic, go to www.plantic.com.au.


Fridge maker heats up thermoforming lines

Global appliance manufacturer Whirlpool?s plastics operation in Evansville, IN is responsible for thermoforming the plastics inner door panels for more than 5000 Whirlpool refrigerators per day, but three primary thermoforming lines were badly in need of drive and motor upgrades. Whirlpool determined that the lines needed electrical and mechanical power transmission work, including shaft and motor adapters, gear boxes, servomotors, drives, wiring changes, and PLC upgrades.

The extent of the work pointed to extended shutdowns over Christmas, but with the help of distributor Morrell Inc. and electric drive and control supplier Bosch Rexroth Corp., Whirlpool was able to upgrade the lines over two weekends in November.

The first target for the upgrades were the servomotors and drivers on the de-stacker portion of the thermoforming line that picks plastic sheets from a stack and indexes them into preheat ovens prior to thermoforming. Working with a stack of 225 thin plastic sheets, the process has eight distinct moves, all occurring within 20 seconds. Stack heights adjust as sheets are picked up, and the de-stacker rack must descend at high speeds until it trips a switch and decelerates as its vacuum cups approach the sheet surface. This required stopping the drive in a torque mode, and thanks to the retrofit, five seconds were removed from that particular cycle.

Whirlpool, which has six other thermoformers for cabinet liners, moved on to upgrade the transfer drives of all three door-liner machines, shaving an additional two seconds from their cycles.

For the upgrades, Whirlpool used the Ecodrive servodrive system, suitable for applications of 1 to 27 kW, and especially applicable to control and positioning tasks. The drives feature positioning block mode, angular and velocity synchronization, cam and cam-shaft functions, as well as an integrated virtual-axis generator. The driver can be directly connected to all recognized main voltages without a transformer, including 3 by 220V and 3 by 480V. Single-phase mains can be used, but with reduced power. Rexroth MKD servomotors, which are IP65-rated and come standard with an incremental encoder, were also used, as was Rexroth Drivetop software. For more information on Bosch Rexroth?s drives, go to www.boschrexroth.com.


Wood-plastic profiles head upstream

Keller Plastics? (Manchester, NH) efforts to open new markets for plastic-wood composites has found success in extruding profiles that become the gunwales serving as the frame on this We-no-nah fiberglass canoe (for more on Keller see ?Wood-plastic composites to enter new markets? in PM&A?s Sept./Oct. 2005 issue, pg. 20). Keller recently added an extrusion line, with requisite downstream equipment and staff, dedicated to exploring new technologies and formulations. Markets outside of decking that the company is exploring include trim, fascia, and decorative profiles used in furniture, office partitions, and window blinds. For more information about Keller Plastics go to www.kellerplastics.com.

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