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Robots, the Plastics Molder’s Best Friend

POSTED 07/23/2015  | By: Tanya M. Anandan, Contributing Editor

Plastics molders’ best friends come in all shapes and sizes. One thing they have in common – they’re all robots. These showstoppers were everywhere at the NPE Expo in March, even gracing the cover of this plastics industry magazine.

Robots are not new to plastics processing, but they’re certainly garnering more attention. Cartesian or linear robots, sometimes called beam robots, have traversed the industry for decades, loading and unloading injection molding machines with deft speed. By brands often exclusive to the industry, such as Sepro, Yushin, and Whittmann Battenfeld. But a closer look reveals traditional robot manufacturers like ABB, Stäubli, and KUKA, plus a new breed of cage-free collaborative robots making moves in plastics.

New, four-axis linear servo robot for pick-and-place injection molding applications features a unique design. (Courtesy of ENGEL North America)Gains in productivity, quality, product life cycle flexibility, and labor savings are driving the interest in automation among large and small companies alike. Meanwhile, trends in multi-shot molding, in-mold labeling and decorating, and composite part fabrication are boosting the demand for advanced manufacturing methods.

The North American robotics market had its strongest year ever in 2014, according to statistics from the Robotic Industries Association. Other than automotive, the largest increase is in plastics and rubber at 25 percent. By all accounts, 2015 is poised to break more records.

In turn, some robot OEMs are ramping up to meet the demand, including Whittmann Battenfeld with a reported $1 million expansion at its Connecticut plant and Yushin with a $2 million expansion in Rhode Island. These robots not only make plastics, they create jobs.

According to the International Federation of Robotics, which tracks worldwide stats, 2013 was also a record-setting year. IFR notes that the plastics and rubber industry continuously increased installations between 2009 and 2013, posting a 110 percent increase. Get the full story here.

So why the big surge and who has the most to gain? Well, it depends on who you ask.

In this ‘Why I Automate’ episode, a plastics manufacturer explains how they grew their business and workforce with robotics automation.

Productivity Gains
ABB Robotics recently opened a new robot factory at its North American headquarters in Auburn Hills, Michigan. Helen Ke Feng, ABB’s Global Segment Manager – Plastics, credits productivity improvements as one of the top reasons plastics processors adopt robots.

“We’ve seen cases where customers have achieved 15 to 30 percent productivity increase after they installed robotic automation,” she says. “That means a lot in terms of competitiveness and also their overall production costs.”

Feng says another goal is to improve quality to increase yields. “This is especially beneficial with some of these carbon fiber composite materials, where the material cost is extremely high. If you can save raw material costs, it benefits you on the overall production costs as well.”

With product life cycles getting shorter and part changeover getting more frequent, flexible automation is definitely an advantage.

Jay Sachania, General Manager of Automation for ENGEL North America in York, Pennsylvania, attributes the upsurge to cost savings, flexibility, and cycle time. Founded in 1945 and rare in the plastics industry, ENGEL does it all. This family-owned Austrian company not only manufactures injection molding machines, but it also supplies robots and other automation equipment, and provides turnkey systems integration.

Global markets include automotive, medical, packaging, electronics and consumer goods. Clearly, ENGEL has insight from several vantage points into the fast-paced world of plastics processors.

“Customers are basically asking for the cell to do as much as possible during the molding process,” says Sachania. “With some of the applications out there, there’s no way a person can maintain the cycle time requirements for a high-speed application. A person simply can’t keep up.”

This video shows a fully automated injection molding cell for automotive dashboards that combines three production processes into one cell.

ENGEL is the only injection molding machine manufacturer that offers a tie-bar-less design, and is celebrating the 25-year anniversary of its patented technology. This video shows ENGEL’s tie-bar-less machine in action.

A typical injection molding machine has four tie bars, two upper and two lower, that help stabilize the moving platens. ENGEL’s design eliminates these bars entirely while still maintaining the parallel position of the platens. This allows for large molds to be used on a smaller machine and is ideal for robotic automation, as there are no tie bars to get in the way.

In addition to its established viper line of linear robots, ENGEL recently introduced its e-pic linear servo robot (pictured previously) geared for pick-and-place applications on low-tonnage injection molding machines. The e-pic has a unique, hinged design that allows it to operate in a large work envelope but fold in on itself for a compact footprint when needed. Plus it’s made of lightweight composite materials for faster cycle times and less energy consumption.

“It’s a design that didn’t exist in the market,” explains Sachania. “If you look at the kinematics of that particular robot, you will see that the x-axis, as we call it, moves in and out. It basically moves out of the way if there’s a mold or some other obstruction in its path.”

This video demonstrates the ENGEL e-pic robot. Note the unique movement of the “x-axis” as shown at 3:07 in the video.

Beyond the Cartesian axes, the c-axis on the end of this robot arm provides a rotational up-and-down wrist-like movement. Gaining in popularity, linear robots with servo wrists in a, b and c axes are designed for complex demolding and secondary operations.

Sachania says the advantages of linear robots are speed and cost. Compared to 6-axis articulated robots common to machine tending applications in many other industries, Cartesian robots are generally less expensive.

Shelf-mounted six-axis articulated robot allows for more flexible handling of parts in injection molding machines. (Courtesy of ABB Robotics)“They are much faster,” he says. “You’re looking at more cycle time advantages because you don’t have to manipulate the axis around.”

He says ENGEL, as a systems integrator, considers each application individually to determine the best solution, whether it’s a Cartesian robot or a 6-axis articulated robot, or yes, even a SCARA. Check out the whirling SCARAs in this production cell for an intricate sensor housing requiring 15 inserts per cavity in a four-cavity mold.

Six-axis articulated robots are renowned for their dexterity and flexibility. ABB’s Feng compares them to their Cartesian cousins.

“In the machine tending area, when the weight of the part is smaller and especially when the cycle time is shorter, it’s mainly the Cartesian or linear robots that you see in injection molding. But when you need manipulation inside the mold, like for insert molding, or when you’re taking the part out and you need some combination of work outside of the machine, then you see more of the six-axis robots. That’s the trend. Customers are looking into the six-axis robots that can offer them more flexibility, especially right now when product life cycles are getting shorter.”

“In the past, six-axis robots have been viewed by injection molders as expensive and somehow complicated to operate,” explains Feng. “But as the technology advanced, the cost of robots declined, and the programming of robots became easier, those injection molders or plastics processors began to realize the benefits of using more robotic automation in their production. Even in China, they’re using six-axis robotic solutions to address the challenges of increasing labor costs. They can’t find skilled operators. In the U.S. and Europe as well, there is ongoing reshoring production.”

Feng says six-axis robots play a larger role when you have a complicated, or complex, molded part.

“If it’s a complicated part, you can’t directly eject it from the mold. Because of the mold or space limitations, you need the six-axis robot to help you rotate the part and maneuver it out of the mold. The benefit of that is you can have the robot doing two jobs. Not only taking the part off the mold, but also while it’s waiting for the mold to be reopened, you can have the robot performing additional work. That increases productivity and is why six-axis robots are getting more popular in plastics processing.”

Six-axis robots can be shelf-mounted on top of the injection molding machine or mounted next to the machine.

“ABB has both shelf-mounted and floor-mounted robots,” says Feng. “It really depends on the space availability and also the overall factory layout. If you have limitations overhead, then you may prefer to have a robot next to the machine on the floor. If you have floor space limitations, then you may be looking at the shelf-mounted robot.”

Full Integration
Robots in this industry come in coats of many colors. Sometimes they’re gold, or blue, and other times green. Nevertheless, they perform their tasks as assigned and represent their respective brand-of-the-moment with distinction.

Six-axis articulated robot services an injection molding machine producing composite automotive brake pedals. (Courtesy of ENGEL North America)See how a six-axis and a SCARA, both Stäubli robots, team up to mass-produce brake light switches in this injection molding cell.

In this video, composite automotive brake pedals are manufactured in a one-shot process using an ENGEL insert injection molding machine serviced by an ENGEL easix robot (pronounced E-A-six, for easy six-axis integration). Compared to steel brake pedals, the composite part results in a weight savings of approximately 30 percent, according to the company.

Sachania says ENGEL’s easix robot is fully integrated with the injection molding machine, so you only have one control system and one programming language. This improves ease of use. It also has cycle time advantages and cost savings, since you don’t need to integrate two separate platforms from different providers.

“Automotive has been, and still is, the main industry for robotics and automation use given the size of plastic automotive parts like bumpers and dashboards,” says ABB’s Feng. “Besides automotive, we see robots used in packaging, especially for in-mold labeling, and in consumer electronics and consumer housewares. It could either be robots near the machine, doing machine tending, or robots in downstream processing, like in deburring, polishing or assembling. Or even in end-of-line production, doing the packing and palletizing of plastic products.”

In this video, KUKA robots work in tandem producing plastic fans in an injection molding cell.

Composites, the Next Wave
The adoption of composite materials across broader industry is a growing trend. Carbon fiber reinforced plastic (CFRP) is increasingly used to reduce the weight of components and boost fuel efficiency, especially in the transportation industry. Some of the carbon fiber parts are even stronger than the steel parts they replace.

“In the past, the main user of carbon fiber reinforced plastic has been aerospace,” explains Feng. “Their volume is small and the processing time is long, so you see a lot of manual production.”

“However, there’s this environmental push coming in the automotive industry, especially in North America where they are trying to reduce the weight of vehicles,” she continues. “CFRP is one of the options they are investigating. They need to meet the requirements of mass production of automotive parts and also they need a stable, high-quality process making high-quality parts at relatively faster speeds. That’s where we see automation can help, so we already have some initial studies underway.

Robots can be used in the picking and placing of the cut prepreg pieces, as well as in automated tape lay-up (ATL) and automated fiber placement (AFP). Here’s a jumbo-sized AFP project where you wouldn’t want your process to be off, even a smidgen.

“Because of the material change and processing change, it has some new challenges that we need to find solutions for,” says Feng. “That’s the other area we are looking into, such as cutting, trimming, and drilling of composite components, and material handling among workstations. We also see the joining of the composite parts.”

The composites world will continue to present new challenges and opportunities for automation and robotics. We’ll be watching.

Six-axis articulated robot tends an injection molding machine producing plastic components for ear protectors. (Courtesy of ABB Robotics)ROI for SMEs
With labor costs steadily rising, the skills gap widening, and robot technology costs coming down while ease of use is going up, robotic automation is no longer the exclusive domain of multinational conglomerates. Small to medium-sized enterprises (SMEs) can cash in on robots too.

In this video case study, a small injection molder learns you don’t have to be a large company to realize the productivity benefits of robotic automation. The integrated cell uses a vision-guided ABB IRB 1600 robot to load/unload an injection molding machine processing pre-fabricated plastic components for ear protectors. The robot also facilitates plastic waste removal and part inspection.

What was previously a manual process is now a fully automated cell that can run around the clock, even in a lights-out scenario.

“That’s really a big improvement for them,” says ABB’s Feng. “They are a very small company in a country with high labor costs. However, they are gaining very strong competitiveness in the world market. It doesn’t matter if you’re a multibillion dollar company or a small enterprise, there’s always a way that robots can help you.”

Onshore Molding
This next injection molder grabbed headlines as the first manufacturer to have “face” time with a new breed of dual-arm collaborative robot on the factory floor. Even before that, they were making a name for themselves by reversing the flow of the offshoring tsunami.

“We’ve always embraced and used automation to keep our labor costs down,” says Lowell Allen, Sr. VP of Manufacturing for The Rodon Group, a custom plastics injection molder in Hatfield, Pennsylvania. “It’s a one-time expense. Other than a bit of electricity and air, you have something that will work around the clock. Being a three-shift operation, we’re talking about three people we would have to hire for a particular task. If it can be done by a robot, you don’t need three people.”

“Then the next statement is always ‘you are eliminating jobs through automation.’ That’s certainly not the case,” says Allen. “What you’re eliminating are the jobs that no one wants to perform.”

Allen says they run 24 hours a day, 7 days a week. Rodon has 106 injection molding machines with a robot tending each one. “There are 60 servo robots and the balance are what we call ‘pickers’ that automatically remove the runner from the mold.”

Dual-arm collaborative robot packs plastic toy parts into boxes for custom injection molder. (Courtesy of The Rodon Group)Rodon has been a proud advocate for the Made in America Movement and a fervent voice in the risks of offshore sourcing. With its “Cheaper than China” pricing policy, this family-owned custom molder has experienced firsthand the benefits of automation by reshoring billions of manufactured parts back to the U.S.

Primary markets include windows and doors, medical and pharmaceuticals, construction, food and beverage, and toys. Rodon is a subsidiary of K’NEX Brands, known for its popular creative building toys.

“Our niche in this industry is high-volume, close-tolerance injection molding,” explains Allen. “This was the first type of manufacturing that went offshore. In order to maintain a competitive edge, we started adding robotics to fully separate the parts from runner systems, and stack and pack parts. The one thing that China will still beat you on is labor. If we had to have a person sitting at a machine 24 hours a day, we would probably get killed. Now put a robot on that machine and all of the sudden you’re competitive.”

“We design and build all of our tooling in house. Not only our end-of-arm tooling, but all of our injection molds are designed and built here. We’re doing a fair amount of mold changes every day. If something breaks down, we simply walk through the doorway to the tool room and get it repaired quickly. Uptime is really how we make money.”

Collaborative Robots
In addition to its 100 employees, Rodon has a humanoid on staff. Rethink Robotics’ dual-arm collaborative robot, Baxter, has been an integral member of the automation team since its pilot program in 2012. Rodon was one of the first manufacturers to deploy the robot in production.

Baxter is used for downstream processes such as stacking and packing parts in boxes. The robot works alongside employees without the need for safety caging. Rodon’s CEO shares “What It’s Like to Hire a Robot” in this recent article.

Other types of collaborative robots are deployed in the shops of plastics processors around the world. Check out this video.

Here’s a completely different take on human-robot collaboration, this time for small-batch injection molding.

For more information about collaborative robots and safe human-robot interaction, check out Major Robot OEMs Fast-Tracking Cobots, which contains links to additional publications on this subject.

Linear servo robot with a second/runner arm packs plastic toy parts into boxes post-injection molding. (Courtesy of The Rodon Group)Lights-Out, Hands-Off
The bulk of Baxter’s robot coworkers at Rodon are beam-style, linear robots with up to 7 axes, supplied by Yushin America and Star Automation. The robots are mounted above the injection molding machines and are often used for hands-off molding. Allen calls this process “shoot and ship” which means the robot goes in and grabs the parts from the mold and places them directly into the box. The box is then sealed. No human hands touch the molded parts.

“If you don’t have a beam robot, you’re dropping parts directly into a box or onto a conveyor belt, either of which is a relatively dirty way to do it,” explains Allen. “Conveyor belts are magnets for dust and dirt. Under the mold is not a great place because there’s grease, springs, and other things that can fall into the box. With a beam robot, you take the parts out of the top of the mold, traverse down the beam, and place them directly into the shipping container.”

“There is a lot of QC involved with many of our jobs. We are also HACCP compliant, which is a food safety accreditation. It identifies areas where contaminates could come in contact with food-grade or food-contact items and cause potential harm. We have machines that are designated just for the HACCP program.”

He says these dedicated machines are equipped with vision inspection equipment by Keyence. “We have 22 of their vision systems that pretty much do 100 percent of our part inspection. Some of these parts are such high-volume and go through high-speed automation that if there’s even one bad part, it can jam up the equipment and cause a lot of downtime. We ensure those particular parts are automatically inspected.”

“We make a couple billion parts per year for our food-grade products alone,” says Allen. “With K’NEX we’re close to a billion parts a year.”

In 2013, Rodon added six servo-driven hydraulic injection molding machines to its fleet. These hybrid machines combine advantages of hydraulic and electric injection machines.

“They are virtually as energy efficient as a full electric, yet they have all the power that a hydraulic machine can deliver,” says Allen. “It’s a servo-driven hydraulic that only requires 40 percent of the oil capacity of a full hydraulic machine, yet it delivers all the power we require for injection, ejection and speed. It’s a very efficient way to mold.”

They upgraded some of their end-of-arm tooling to incorporate sensors, also from Keyence, that help prevent the robot arms from colliding with obstructions. The sensors are also used to verify pick-and-place locations with better accuracy and detect parts that come up short. This happens when an inadequate amount of plastic is injected in the cavity, causing defects in the parts.

Facility Manager Tony Hofmann says advanced user-friendly features are making their beam robots easier to program. “With all of the different ways that we want to package and all the different jobs that are scheduled, it’s very handy. Instead of having to make a phone call and spend $500 for a program change, one of our setup guys can do it. It works out well for Rodon.”

Well, indeed. Rodon continues to set benchmarks for SMEs and even large molders looking to automate.

Robot end-of-arm tooling with slide-out nippers and part sensors for plastics injection molding. (Courtesy of ASS End of Arm Tooling, Inc.)Clever EOAT
Charged with the dicey business of extracting newly formed parts from rapidly moving molds, end-of-arm tooling (EOAT) must be nimble and lightweight, especially if it’s perched on the end of the low-payload Cartesian robots common to this industry. It’s often called upon to perform multiple tasks, not only securely gripping parts for demolding, but also adding components for in-mold assembly, labeling, or decoration. Multiple on-board nippers remove sprues, runners and other waste, while individual sensors verify part presence and perform quality checks. All of these operations in a continuous battle to reduce cycle time.

Because of these unique challenges, certain end-of-arm tooling suppliers tend to specialize in this industry. Known as the company with the “funny name but serious product,” ASS End of Arm Tooling, Inc. embraces its moniker and humble beginnings.

“Back 35 years ago, our founder worked for a company that made injection molding presses. As a young engineer he was assigned the task of designing a tool for the robot so it could grab the parts,” explains Juergen Kortberg, Vice President of ASS End of Arm Tooling in Plymouth, Michigan. “He eventually started his own company in his garage. We were the pioneer in end-of-arm tooling specifically for the plastics industry.”

Founded in 1982, ASS Automation Systems is the parent company where the majority of components are manufactured in a factory near Cologne, Germany. All of the components fit together like an erector set, enabling customers to easily build their own custom robotic tooling.

“Seventy-five percent of our business is in the parts business,” says Kortberg. “People like our components because if you stay in our product line, everything fits together. We were the first company to do this. Even if we come out with new gadgets, they all fit within the erector set. It’s like a do-it-yourself kit.”

It doesn’t hurt to have a memorable name either. The company puts it on every component, along with the part number and description, so customers can order it right from the end-of-arm tool without consulting any documentation. They sponsor “holes” at golf outings and hand out candy at trade shows. ‘Care for a piece of ….’ You get the idea.

Kortberg says their EOAT handles part sizes ranging from automotive emblems and handheld consumer goods to whole trash cans, and huge bins used in crop harvesting. In addition to standardized end-of-arm tooling components, the company designs and builds custom EOAT for applications requiring complex tools or for customers with high-volume needs.

Automotive is their largest market. They supplied custom EOAT for demolding the fascias of the 2014 Chevrolet Corvette. The aggressive geometry of the fascia posed a significant design challenge.

With a Soft Touch
One of the challenges in the automotive industry is demolding parts without marring the surface. Sensitive parts such as polycarbonate headlamp lenses and chrome-plated plastic components require a special touch.

“We’re always the first ones that have specific off-the-shelf components that are driven by those demands for new technologies,” says Kortberg. “The latest we have is a new coating for components that come in direct contact with parts. We call it Soft Touch and it’s a proprietary coating on our components.”

He says they built a new area in their factory in Germany that is temperature and humidity controlled specifically for applying the new coating to components.

“That coating has to withstand temperatures in excess of 240 degrees Fahrenheit. Plus it has to be scratch resistant and silicone-free, and it cannot put any markings on the material that it comes in contact with.”

They are also supplying most of the automation end-of-arm tooling for the 2014 BMW i3, the world’s first production car with a carbon fiber composite passenger compartment. 

Custom robot end-of-arm tooling for handling carbon fiber reinforced thermoplastic material during automotive seat molding process. (Courtesy of ASS End of Arm Tooling, Inc.)Kortberg says being on the forefront of new technologies and processes drives the evolution of their components. In another application for composite materials, ASS End of Arm Tooling developed custom EOAT for handling organo sheets for a research and development project conducted by the Fraunhofer Institute for Production Technology (IPT). Supported by the German government, the project involves automating the manufacturing process for creating lightweight automotive seating.

ASS developed the robot end-of-arm tooling to help automate the molding process.

Designing an EOAT to manipulate these organo sheets was no easy feat. Kortberg describes the challenges.

“Especially for those organo sheets the manufacturing process is even more complex, because the ‘cold cloth’ that is already flexible and is being gripped by the end-of-arm tooling is then put in an oven while the end-of-arm tool holds onto the sheet. When the sheet is heated it becomes more flexible.”

He points out the four expandable gripping devices (in the pictured EOAT) specially developed to measure and adjust the tension to ensure the organo sheet does not sag during processing.

This article discusses the CAMISMA research project in more detail.

Kortberg says end-of-arm tooling is often an afterthought, resulting in costly redesigns. “We know people that had to scrap their tooling because they couldn’t automate it. Then they want to throw more money at the EOAT to make up for the poorly designed tooling. We’re talking about multinational companies, not mom-and-pop shops.”

He advises robot users to consider the end-of-arm tooling earlier in the development process.

Systems Integration
Robot systems integrators pull it all together by brandishing specialized expertise to design and build the most efficient robotics systems, end-of-arm tooling, fixtures, and ancillary automation equipment for a safe, productive process.

“One of the things that I noticed at the NPE show and the K Fair in 2013 is a lot more automation,” says Robert Battaglia, Director of Factory Automation for Axium Inc., a robot systems integrator in Montreal, Canada, specializing in material handling and assembly. “A lot more companies are using robotics to automate.”

He credits increased return on investment as a major factor. “It’s not only the cost of the robot you have to look at, but the cost of integrating it, what you need around it, to feed the robot, the tooling, all of the accessories – everything is getting more competitive. Everything is getting easier to use. Plus the cost of manpower is going up. I think there’s a huge interest for companies to start automating.”

Plastic fuel tank welding line puts robots to work boring holes, spin welding and hot-plate welding. (Courtesy of Axium Inc.)Axium was at NPE promoting its post-mold finishing lines for plastic fuel tanks. The process combines thermoplastic welding technologies, vision guided robotics, material removal, and other automated processes into a turnkey assembly line for automotive OEM suppliers.

This video shows the plastic fuel tank welding line in action from start to finish. In the first processing station, the robot bores openings for the fuel sending unit (FSU) and the inlet check valve (ICV) before welding begins.

Hot-Plate Welding The robot systems integrator uses a patented hot-plate welding process to assemble the ICV in the blow molded fuel tank. You can see this process performed at 1:38 in the video.

Hot-plate welding uses a heated platen pressed against the components to be joined (in this case, the ICV and the tank body) until the edges of each component melts. Then the components are pressed together so the melted edges fuse as the plastic cools.

The applied force and the displacement (how far the parts are pushed into each other) must be carefully controlled to ensure a sound weld. Both the amount of time the heated platen is applied to the components and the transition time between when the platen is removed and the components are pressed together are important. The result is a strong, hermetically sealed joint.

In the automotive sector, hermetically sealed joints in fuel tanks are essential for emissions control. Battaglia says hot-plate welding is a common process in plastic fuel tank assembly, but Axium takes the process up a notch.

“When we start heating up the plastic of the tank, we’re doing it with a controlled force and at the same time we’re keeping track of how much we’re removing and how much we’re penetrating into the tank. Everyone does that. What we do differently is that we’re using the same technology, the same force sensor, the same displacement sensor, to detect improperly fitting parts. As the part (ICV) enters the hole, if it rubs up against the side of the hole, because the part was maybe poorly molded or was crooked, or we’re offset in the hole, we’re able to detect that extra friction. We’re able to determine if there is something wrong with the part and if we need to scrap it.”

Axium uses its WeldSight-3D vision system to scan the opening before inserting the ICV in the fuel tank.

“It does a 3D scan of the weld pad,” explains Battaglia. “It finds the center and the orientation of the weld pad, and then it gives all of that information to the welding robot so it can adjust the weld point and corresponding approach path to make sure that the part is going to be welded fully parallel to the weld pad. We’re basically using the vision system to compensate for any irregularities in the molding process.”

“This results in a better quality weld and reduced cycle times,” he adds.

Spin Welding
Axium uses spin welding to assemble heat shield studs to the tank, as shown near the beginning of the video. Spin welding involves rotating a component at high speed (one of the studs) and forcing it against a stationary component (the fuel tank). The resulting friction between the components causes the plastic edges to heat up and melt, welding the two components together.

“Spin welding is used solely for non-hermetic welds,” says Battaglia. “It’s only used for clips or small components that need to be welded on the surface of the tank, but not where you’re penetrating the interior."

Axium’s plastic fuel tank welding line is based on a modular design called the skid concept, in which each robotic weld station is mounted on a metal skid. This reduces installation and start-up times, and allows for cells to be replaced or removed easily.

Extensive experience automating systems for welding plastic reservoirs gives Axium special insight.

Vision guided robot performs 3D scan of automotive fuel tank prior to hot-plate plastic welding process. (Courtesy of Axium Inc.)“We’ve been doing it for 16 years now,” says Battaglia. “Not only do we know the automation side, but we also know a lot about plastics, and particularly fuel tanks. We know how long it takes to weld the components. We know how they deform. We know how varied they are coming from a blow molding press, so we know how to design around that.”

“The WeldSight-3D system was developed specifically for this process because we know that molded fuel tanks have variances,” he continues. “In order to adapt to those, we came up with a system that does it automatically. We have a lot of experience knowing how a tank moves, how it reacts, and what tank shapes tend to flex more, so we can design our fixturing accordingly.”

Using robots coupled with sensors consistently controls the force, displacement, and heating and transition times critical to the success of these plastic welding processes. Last month, we showed you many examples of how smart sensors are raising the robot’s IQ in Intelligent Robots: A Feast for the Senses.

Axium uses similar robotic welding technologies for assembling other types of plastic reservoirs, such as for food or oil containment, and for assembling plastic venting systems and ducts. Axium also integrates systems for robotic deflashing of plastic reservoir tanks, pipes, and tubing.

There are no losers here. Whether it’s a 3-axis or 5-axis linear robot, a fully articulated six-axis robot, or a smiling humanoid ready to box your plastic parts, it’s the robot users that have everything to gain.

RIA Members featured in this article: