Nordson produces medical products in cutting-edge facility
Founded in 1968, Value Plastics may have been one of the first lights-out molding operations in the plastics industry. In its early years, the owner and his family lived on the second floor of the factory to answer machinery malfunction alarms at night.
Today the company, now known as the Nordson Medical Fluid Management Manufacturing Facility, operates from a state-of-the-art plant where 48 unattended injection molding machines and a complement of robots are molding, assembling and packaging 1.2 million parts every day in a huge clean room.
No one needs to live upstairs in the 2-year-old, 115,000-square-foot plant in Loveland, Colo. The current managers lock the doors and leave every evening and don’t bother with remote monitors, pagers, iPad links or other devices to tell them there is a malfunction.
The heart of the plant is a 37,000-square-foot Class 8 (Class 100,000) clean room that has space for as many as 56 molding machines, robots and assembly and automated packaging operations. The 48 electric machines currently in place consist of 47 Fanuc Roboshot presses ranging from 17 tons to 198 tons of clamping force, although most are 55-ton models. There is one Engel press.
Sprue pickers and other robots are from Yushin. Most of the servo robots have dual-telescoping-arm units with a servo wrist.
The lifeblood for the clean-room operation is a sophisticated materials-handling system from Piovan. “We designed our material-
handling system to meet our business needs,” plant manager Ray Townsend said. “It allows us to run lights out, which is the key to our business.
“Lights-out manufacturing is a mind-set for processing,” Townsend said. “It starts with picking the right equipment, then following a super-good preventive maintenance program with tight tolerances on everything, then training on all the equipment to make sure everyone knows how it works. Part design and tool design are also key to our success to support the lights-out environment.
“When everything comes together and you have a solid, validated process, you don’t have much tweaking to do. Everything just runs,” he said.
The plant is set up on the philosophy that if a part is rejected, it is kicked out, and the machine resets itself and keeps running. If many are rejected or there is a problem with the molding machine, the machine shuts down while others keep running. “Everything is recorded, so we can figure it out in the morning,” Townsend said.
Process production is monitored by Linki, a system specific to Fanuc/Cincinnati Milacron Roboshot machines. It is integrated with Nordson Medical’s enterprise resource planning (ERP) system from IFS Americas, Itasca, Ill. The ERP system provides a wide range of custom production reports that are accessed through the company intranet.
An integrated plant control system from Johnson Controls monitors production systems like chilled-water units and air compressors, and the Piovan system watches materials-handling equipment.
Nordson Corp., based in Westlake, Ohio, acquired Value Plastics in 2011, then located in Fort Collins, Colo. There was no room to expand in Fort Collins, so in 2014 Nordson broke ground on the state-of-the-art plant in Loveland. The first molding machines were moved into the new plant in the fall of 2015. Nordson Medical has space to build two more plants of the same size on the Loveland site.
Townsend said the previous plant had a custom materials-handling system built about 20 years ago by Motan. “It was ahead of its time,” he said. “It went through a number of improvements over the years, and we came to rely on the ability to pull any material from any hopper to any machine.”
When it came time to design a materials-handling system for the Loveland plant, Townsend said he was unimpressed by the systems he was shown.
“We wanted to be able to deliver material from any hopper to any machine in an automated way with absolutely no manual intervention,” Townsend said. “The suppliers kept telling me they couldn’t do that.”
Eventually, he had proposals from four equipment suppliers. One was the Italian manufacturer, Piovan, which has a subsidiary, Una-Dyn, in the U.S. Townsend had first met representatives from Piovan at an NPE show and liked the construction of its equipment. “They were the only company that said, ‘Oh yeah, we can do that,’ ” Townsend said.
That was possible, said Una-Dyn President William Goldfarb, because Piovan has a broad product portfolio, with worldwide installations that provide the design basis to deliver what Nordson wanted — any material to any machine without human intervention. “For the other companies, it was something they had never done before, so they would need to experiment, whereas we had working examples and experience to draw upon.”
The brains of the materials-handling system is Piovan’s Winfactory 4.0 software designed for smart factories. Each group of machines, such as dryers, loaders and blenders, has its own controller. The Winfactory computer system manages all the controllers, giving an operator access to any part of the system through a visual interface.
“Winfactory makes machine group-to-machine group connections,” Goldfarb said. “Machine groups can assign themselves to a particular drying station and upon evaluation of the aggregate demand, only then will it release validated, conditioned material,” he said. “Assigning a machine to a dryer hopper that does not have enough capacity is one of the most common errors of less sophisticated or manual systems.”
The Winfactory system is based on OPC-UA and can connect all Piovan machines, as well as equipment from other manufacturers. It also optimizes energy consumption, collects data needed to validate medical products and interfaces with the plant’s management system.
“There is no way for a material-handling system that does not monitor material as it moves through the system to be able to accurately calculate that,” Townsend said. “This system is monitoring the entire throughput. When we pull material out of the molding machine, it measures how much came in and calculates the throughput.” It uses that information to make correct materials-handling decisions.
Resin is delivered to the plant about two times a week and it is bar coded before going into one of four surge bins that can each hold 10,000 pounds of resin, which is a single lot of resin. Nordson buys material in the biggest lots possible to minimize lot changes. Resin used in smaller quantities stays in gaylords but also gets a bar code. This step provides the materials-handling system with the data to identify and locate any material in the plant as it is blended, dried and consumed by the molding machines.
From the machine setup, the materials-handling system can determine how much dried resin it will need. The system knows the amount of material in the dryers and the time it will take to reach optimum conditions, so it knows how many machines can be connected to the dryer.
The blenders take that information and feed the dryers. At each step of the way, the system knows the consumption rate and directs other components to make that amount of material available.
Dryers can be put into idle or started automatically, and the volume of resin can be slowed down, based on demand.
The system can also automatically manage two speeds for conveying, based on the recipe of the product the machine is running.
Some of the dustier resins are treated by Pelletron dedusters before being loaded into the handling system. “We dedust as it loads in, so we are not moving dust through the system,” Townsend said.
There are 10-15 mold changes per day. Material changeovers are quick. The new material is ready when the change occurs and conveyors are purged clean. A centralized vacuum at every press cleans the receiver. Total time is 8-10 minutes, Townsend said.
In addition to mold changes, Nordson maintains 100 percent material traceability on lot changes. To safeguard the integrity of the process, molding machines are purged each time a new lot is introduced. In addition, the receivers and hoppers are cleaned, even when the same type of material is going back into a hopper. “We never load new material on top of old material,” he said.
Townsend said recipe management is the key to material changeover. “The system will not allow you to pull material that is not dried to a molding machine,” he said. “The resin has to go through the cycle and meet certain conditions that are monitored. The temperature has to be correct and the airflow right for the specified amount of time. There is no way to override it.”
Resin hoppers have a recirculation feature that moves material from bottom to top to keep it fresh and dry. Keeping the material below the hopper cone dry can be a problem because the airflow is typically from the hopper cone up.
The plant has an automated regrind-recovery system that Goldfarb termed unique. It uses Piovan’s Easylink automatic coupling stations to move regrind from any press to a central regrind location. Each molding machine has its own robot-fed grinder that needs to be unloaded, and there is a line for each material type at each press. Since the materials-handling system knows which material is at a specific press, it can automatically direct the regrind to the correct location. Nordson trades its regrind material for a discount on virgin resin since it cannot use it for medical parts.
“The regrind-recovery system is a huge deal,” said Townsend. “We could never run lights-out in our facility if you had to do it manually.”
Townsend said it takes only one or two employees to keep the materials-handling system operating. “Their primary job is switching out gaylords,” he said.
The injection molding presses inside the clean room are arranged in rows of seven machines on each side of a utility corridor. Utility corridors, which are outside the clean room, are large enough to walk through and access the various lines and pipes running between the materials-handling system and presses. There are more than 5 miles of stainless steel tubing in the plant.
There are three connections through the clean room wall for each machine, with lines for materials, vacuum and regrind removal.
The total materials-handling system has four dryers and 25 drying hoppers. Normally, two dryers remove moisture from the material from 12 hoppers and the other two handle 13 hoppers. If demand drops, dryers transition to an idle state automatically. If an alarm goes off at night and one dryer shuts down, the other two can run all 25 hoppers. “That is key,” Townsend said. “That is something other systems don’t do.”
Townsend said it is important for all dryers to run all the time. This avoids a long period when a dryer is turned on and has to get up to operating temperature and stabilize the material. “One may be idling, but it is ready to accept the needs of the system if the other fails,” he said.
Hoppers are generally dedicated to a specific material. The materials-handling system tracks material into and out of the blenders so that only validated material goes into a hopper for drying.
Once the material is dry and the handling system verifies that temperature and airflow requirements have been met, three automatic Easylink coupling stations direct the resin to a pumping station so that any material that is ready for processing can be delivered to any injection press.
Material is also weighed at the receiver on the machine and that information is used by the materials-handling system.
Townsend said the decision to use Fanuc Roboshot presses came in part because of the type of medical products Nordson manufactures. “We evaluated all-electrics on the market and went with the most accurate, repeatable and robust machines we could find,” he said. “We also looked for options that fit our business and the niche we mold in, often borderline micro molding. We continue to challenge the industry and research new technology from all suppliers.”
The company plans for presses to last 15 years or 15 million shots. “We try to budget to replace at least one machine a year along with adding additional machines for capacity. We have had presses last 21 years and 22.84 million shots, but try to replace them ahead of those numbers,” he said. “Even with impeccable maintenance and calibration, they are limited by the reaction times of a 21-year-old computer. Spare parts, particularly electronic components, are nonexistent [after that time].”
The lone Engel press is a two-shot, 60-ton all-electric with full process monitoring capability on both the first and second shot. It can control two servo-driven motions for both in-mold and platen rotation. It also has 36-zone sequential valve gate and temperature control. Nordson bought the machine for an R&D project and Engel was the only company that could deliver what the company needed from an options and technology standpoint, Townsend said.
In addition to the 48 presses, the clean room contains areas for assembly and other tasks. Much of the parts packaging is done at the press. Parts are inspected and anything that is rejected is diverted to a reject bin. Good parts go through a deduster, then are dropped into a container. Once the container has the correct number of parts, a conveyor moves it away and another container is brought in.
“If we did not do it here, we would have to take bulk parts with unknown counts down to one of our baggers,” Townsend said. “Then we would have to clean and dedust, count them and put them into a bag. This way, we count at the press and put say 20,000 parts into a container, seal it, put a label on it, drop it into a paper box, seal the box and ship it. It takes all the labor out.”
Nordson uses Wittmann Battenfeld temperature controllers that can heat water to temperatures from 48 degrees to 360 degrees Fahrenheit. Why does the plant need such a wide range of water temperatures?
“We don’t run the same parts on the same machine all the time,” Townsend said. “Sometimes we run materials with a high melt temperature. Most companies might use an oil heater to get the mold hot enough, but we choose to use high-temperature water. Water cools six times better than oil, so you can run faster cycle times. Plus, it is safer.”
Every molding machine has a system that shuts down that machine and its water supply if a leak is detected.
Mold handling is performed by a team that disassembles the tool, cleans it ultrasonically, configures it for the next job and installs it on a press. They pick up another one and the cycle repeats. “They perform an entry-level toolmaker kind of role,” Townsend said.
The Value Plastics brand lives on as the Nordson Medical line of stock parts. The Loveland plant maintains 67 million parts in inventory. The goal is to maintain 100 days of salable inventory. Parts are such things as stopcocks (one-way, three-way and four-way); six families of quick-connect fittings for tubing 0.25 inch- to 0.5-inch thick; all-inclusive bioprocessing lines with a wide range of fittings, clamps, connectors and gaskets; and check valves. Norton also molds custom parts.
Maintenance on everything in the plant is scheduled and recorded in the plant’s ERP system. That includes all processing and materials-handling equipment, molds and tooling, insert sets for molds along with anything that requires calibration. FDA regulations drive the preventive maintenance routine, Townsend said.
Ron Shinn, editor
Just the facts
COMPANY: Nordson Medical
HEADQUARTERS: Loveland, Colo.
OWNER: Nordson Corp.
ANNUAL SALES: Not disclosed