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IMM's Plant Tour: Efficiency comes from self-made automation

August 16, 1999

8 Min Read
IMM's Plant Tour: Efficiency comes from self-made automation

Not many molding facilities in the U.S. have molding wings. There are levels, floors, departments, and sections, but not many are arranged like the Nypro plant in Asheville, NC. It also has a nice walkout basement, thanks to the hill on which it’s built. But that’s for later.

Nypro Asheville is part of the larger Nypro Inc. worldwide molding organization, with plants on almost every major continent on the planet. While it’s easy to be overwhelmed by the size of this company, plants like the one in Asheville remind you that this molding giant is really just the sum of its parts—a series of moderately sized molding plants that compete, as many other molders do, for business. Each manages and markets itself, playing on strengths and specialties. So, what’s so special about Asheville? Let’s go find out.

On the Floor
Molding life at the Nypro Asheville plant revolves around three injection molding wings: east, west, and south. The use of the wing concept gives the plant a hub design (see diagram), which means that each of the three molding areas is easily accessible from a central point. The same holds true for resin, which is delivered to the center of the plant in the basement, and then distributed from there to the wing that needs the material. When IMM stopped in, the east and west wings were loaded with Netstal and Nissei presses (40 total) molding a variety of medical, electronic, automotive, and consumer products. As is the habit of most Nypro plants, this one has a part-pulling robot on every press. The brand in Asheville is Automated Assemblies, and engineers at the Asheville plant make their own end-of-arm tooling. Operators tending machines make sure parts are boxed properly, measure parts to maintain quality control, and help keep presses running smoothly.

As many smart molders do now, Nypro has installed on several presses homemade sorters that put all parts from a cavity into the same container. Nypro Asheville QC personnel then check part quality for each cavity. If a quality problem is detected, only parts from the troublesome cavity are discarded. This saves not only material, but time in determining which cavity is producing defective parts. This is particularly helpful at Asheville, where some molds have as many as 64 cavities, and most average 32 cavities.

Each molding wing also includes two quality stations in the aisle between the presses so that, says Dan L’Ecuyer, account specialist at Nypro Asheville, “no part is more than 30 ft or so from where it’s going to be measured.” For parts with particularly tight tolerances, Asheville runs a half dozen or so molds that transfer on cavity pressure using transducers integrated with control systems provided by RJG Technologies.

In the QC lab just off the west molding wing you’ll find an Avalon SCIII, a vision system recently introduced to the market and first developed with help from Nypro. The Nypro Asheville facility runs a variety of parts with small holes, undercuts, and other details. Small pins in the mold do break occasionally, producing out-of-spec parts. Unfortunately, until the Avalon SCIII was developed, it was not always possible to detect a missing hole, or the presence of an unwanted feature, that would force the part to be scrapped. Joe Freitas, quality engineer in Asheville, says that one particular part ran for several days with a broken mold pin before the customer caught it. Thousands of parts were scrapped at great expense to Nypro and the customer.

The Avalon system allows Nypro to mold an acceptable master part, the image of which is digitally stored. To check a just-molded part to make sure it meets specification, it’s placed in a partially enclosed vision table that uses red light and video cameras to compare the molded part to the stored image. Missing holes or unwanted features are flagged by the software and identified on the screen. With it the QC department can catch bad parts much sooner and the mold can be repaired. “This system has saved our fannies many, many, many times,” says Freitas. “It’s more than paid for itself.”

The south molding wing was empty when IMM visited, but by the time you read this it will likely be filled with another 20 or so presses devoted to a new medical molding program recently acquired by Asheville. The program involves molding a 13-component part for in-house assembly and then delivery to the pharmaceutical OEM.

Under each of the three molding wings is a materials handling basement, loaded with resin gaylords and the usual collection of handling equipment. Two workers per shift manage all of the plant’s material handling needs, which is done with Conair granulators, AEC dryers, Motan loaders, Sterlco mold temperature controllers, and a Motan software control system to coordinate efforts. Equipment is organized in stalls, each of which is associated with its own machine on the floor above. All material is conveyed by dry air.

One of the best design aspects of the plant is how receiving and shipping are organized. Because the Asheville plant is built on a hill, all material is delivered to the walkout basement at the center of the plant. From this lower level it’s conveyed up to the production floor, also at ground level at one end. Finished parts are stored and leave the plant from the other end of the building’s center, on the production level. The effect is that raw material enters one side of the building at the basement level, while finished parts exit the other side on the production level.

The Automation Man
Architectural creativity aside, there is a secret weapon at the Asheville facility. It’s not a molding machine or some other piece of equipment, but a person. He’s the automation engineer (his name was withheld at Nypro’s request). He’s one of those high-energy, technically creative engineers who can turn a typical molding operation into a paragon of efficiency. His specialty is designing and building automation and assembly systems.

Take, for instance, the fiber-optic reel Nypro molds. Designed to hold five miles of fiber-optic cable, the 8-inch-diameter reels are molded in halves and glued together with a foam pad around the hub to cushion the cable. Any imperfection in the alignment of the halves or the foam pad could damage the cable and means the part has to be tossed.

Over one weekend Nypro’s automation engineer designed and built, using only off-the-shelf products, a press-side rotating shuttle assembly system that automatically applies the glue to one half of the spool, pushes the halves together, attaches the foam pad, and holds the assembly together until the glue is set. The system minimizes human intervention, resulting in dramatically improved consistency. The only problem is that the technical drawings for this system exist only in the engineer’s head. “I’m working on putting them on paper now,” he says.

Another system the automation engineer designed and built automatically assembles Johnson & Johnson’s new two-part baby bottle—hitting the market this summer—that features J&J’s Twist-N-Lock mechanism that allows the user to change the feeding angle and promote upright feeding. And in the aisle between the presses in each wing is a Windows-based barcode software system the engineer wrote over another weekend. It generates and prints labels customized to meet each customer’s requirements. In fact, both molding wings are littered with this automation engineer’s creations, most running press-side, streamlining automation and assembly operations for the plant.

Finally, for the big picture, this engineer also wrote a Windows-based production monitoring program that allows almost anyone in the plant with access to a PC to check current and historical operations statistics like cycle time, downtime, and scrap rate. It’s tied to the barcode program to provide complete manufacturing integration. When it was pointed out that there are off-the-shelf products that do the same thing, this engineer’s explanation was simple: “Why would we do that? In less time than it would take us to buy something packaged, and for less money, I can write a program that meets our production needs and does exactly what we want it to do.”

No Blocked Cavities. Period.
There’s something else that makes the Nypro Asheville facility tick. It’s a rule that not one single mold is allowed to run in a machine with a blocked cavity. “Zero does not mean two or three,” says general manager Kim Simpson, “It means none.” It’s a strategy the company implemented a year ago with some trepidation—and customer uncertainty.

As we noted before, this Nypro facility runs high-cavitation molds, some with as many as 64 cavities, and most with at least 32. Max Boller, technical manager of the tool maintenance department and an 11-year Nypro veteran, says many customers feared the policy would force continuous downtime and delay deliveries. “All it takes is one minor flaw in a part and you have a bad cavity,” says Boller.

To cope with the prospect of mounting downtime, Boller and the tool maintenance facility stipulate that all work on a mold be completed before the next shift. “Whatever repair work we do, we want to do it in one shift,” says Boller. The shop’s complement of drills, grinders, mills, EDM machines, and 193 years of combined moldmaking experience make this possible.

The result has not been continuous downtime, but increased yields, healthier molds, and quicker turnarounds. Simpson says the policy challenged employees to be more quality conscious. “It made a major difference in the company that we didn’t expect,” he says. In the process, Nypro’s learned user-friendly mold design that makes maintenance and repair that much easier. “I don’t know any place in the world that does not run with blocked cavities,” Boller says.

Simpson says that with the no-blocked-cavities strategy and a proficiency in assembly, automation, and turnkey manufacturing, Nypro Asheville expects to record 400 percent sales growth over the next five years.

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