Uniloy Milacron adopts aerospace technologies to to deliver higher precision
Uniloy's dedicated, 55,000 sq. ft. mold making plant has historically produced about 3000 cavities a year, but can now handle significantly higher volume thanks to huge reductions in mold processing times from adoption of new technologies and creation of Kaizen improvement teams, said Al Vanover, Mold Division Manager. The changes make the mold division especially efficient at producing multi-cavity unit molds, he said.
Up-grading the Manchester, Michigan moldmaking facility to high-speed, horizontal machining centers and shrink-fit tooling has cut processing time per mold cavity by more than half with superior quality, he noted. "We're getting five times better surface finish by using small tools with finer pick-feeds at higher rpm," cited Vanover. "We're machining closer to the net, electronic model shape to minimize hand work and polishing. In turn, this lets us hold five ten-thousandths (±0.0005") in accuracy from cavity to cavity on unit molds."
The Mold Division is looking to the improvements to broaden its volume of "outside' mold-making business beyond the Uniloy machine family, he said. A leading global manufacturer of blow molding machines, Uniloy has an installed base of over 3000 systems worldwide. At present, the moldmaking business is split about 70-30 between Uniloy machine owners and outside, non-Uniloy machine users, said Vanover. "Our objective is to serve the whole market and bring more balance between Uniloy customers and outside blow molders," he said. "We think we can offer an outstanding package of capabilities to new customers."
The leading producer of dairy molds in North America, Uniloy creates blow molds for all types of bottles, containers, markets and applications — fruit juices, soft drinks, bottled waters, sports beverages, household and personal care products. "We can create custom molds for nearly any kind and size of container, two ounces to five gallons," said Vanover.
Equipped with more than 20 high-speed horizontal machining centers and staffed by 107 skilled trades, Uniloy's dedicated moldmaking facility produces molds on 24/7 production schedule to optimize turnaround time on orders. The size and resources make the mold-making operation especially effective at handling multi-mold, multi-cavity assignments, he said.
"We offer total design/build capability, working with the client from concept to finished container," stressed Vanover. Typically, customers supply the basic concept or a 2D drawing for the container, which Uniloy designers and engineers then develop into 3D using Catia CAD/CAM software and a deep knowledge of blow-molding dynamics. "We find ways to execute the customer's unique styling, while avoiding design features that can present blow molding problems," he said. Adopted from aerospace practice, the Catia engineering software provides superior capability for developing contoured shapes and surfaces, said Vanover. Not as easy to learn as other CAD/CAM systems, Catia generates a maximum number of points for defining complex bottle shapes, creating crisp highlights and details, and blending transitions between surfaces, he explained.
North America's biggest buyer of aircraft-grade aluminum outside the aerospace industry, for the mold-making operations, Uniloy adopted aerospace machining technologies to create more complex mold shapes at higher quality on shorter turnaround. "Our parts differ in size, but the situation's the same — achieving higher throughput with greater precision on constantly changing geometric surfaces," said Vanover.
High-speed horizontal CNC machining centers (HMCs) with Risc processor controls allow molds to be processed at three times faster spindle speeds and up to 10 times faster feeds rates through continuous 2-axis and 3-axis contouring and sharp geometry/axis changes without toolpath discrepancies caused by data starvation, he explained. Rotary tables, standard on the HMCs, allow part faces to be rotated to perform multiple operations in a single fixturing and optimize spindle and tool access on deep cavities and tight features, such as neck areas. He cited a recent project creating molds for a leading brand of cleaning product. "We milled the cavity, cut the pinch-off, drilled all the water lines, and installed pins and bushing, all in one set-up." This one-stop processing avoids the delays, part handling and compounded set-up errors of sequential, multi-step, multi-machine processing, he noted. Finally, machining part faces in vertical attitude with horizontal spindles optimizes chip removal in high-speed machining for superior feature precision, surface finish, and tool wear.
Shrink-fit tooling — pioneered by the aerospace industry — further enhances Uniloy's high-speed machining proficiency by solving problems of deflection and vibration in long small-diameter tools required to create fine details in deep cavities, noted Vanover. Exploiting the physical properties of metals, Uniloy's shrink fit system heats toolholders in an oven and refrigerates the cutting tools before inserting tool into holder. The hot holder shrinks down as it cools, while the tool expands as it warms.
Together, these actions create solid metal-to-metal contact, eliminating any play.
This allows tiny ball end mills — down to 1/64" diameter by 4" long — to run at perfect concentricity without whip, deflection or chatter in precisely machining fine details such as highlight lines or engravings. "We're getting superior surface finish and geometric accuracy on all mold work, but particularly on unit molds where cavities need to be effectively identical," stressed Vanover.
Unique as both a machine and mold builder, Uniloy can perform molding trials for customers on its own equipment, he noted. In-house shuttle and reciprocating-screw blow molding machines allow testing and trail runs on molds after build, especially multi-cavity units. "You don't have to worry about installing a mold, find something's not right, then remove the mold and return it to the mold builder," he said.
"We think we offer the blow mold industry's most integrated, comprehensive capabilities in custom mold design and build," said Vanover. "We deliver the total solution, now faster than ever, at highest levels of quality and at very affordable prices."
For more information on Uniloy mold building service, contact: Alan W. Vanover, National Sales Manager – Molds, Uniloy Milacron, 10501 Highway M-52, Manchester MI 48158. Tel: 734-428-2278. Fax: 734-428-0171. Email: Alan_W_Vanover@uniloy.com
Source: Uniloy Milacron