A company that supplies a single, patented material has a measure of protection. No one else can offer quite the same thing—until the patent runs out. Then anyone anywhere in the world is free to offer a competing version of the product. It's the situation that Victrex PLC faced.

The origin of the company dates back more than 25 years, when it was formed by Imperial Chemical Industries to market a patented polymer, polyetheretherketone, which is more easily remembered as PEEK. It is a premium-priced, high-performance thermoplastic, with exceptional wear and heat resistance.

In 1993, a management team that includes the current CEO, David Hummel, bought out the company. By the time the patent expired several years ago, the company had decades of experience working on PEEK applications with customers.

Film development: An extruding machine at a new plant in England can produce a variety of PEEK films in thickness ranging from 6 to 750 micrometers, according to Victrex, the manufacturer.

The company has continued to work with customers on specialized uses of the material and has also launched additional product lines based on it. The company has established a business, for example, in industrial coatings using PEEK under the brand name Vicote. More recently, it has begun to produce a variety of industrial films, which it collectively calls Aptiv.

According to Hummel, the decision to launch a line of films developed out of contacts with customers. "After talking with end-users, we found they wanted PEEK in a new form," he said. That form was a film—actually a family of films—offered in crystalline and amorphous forms, both of which are available with a mineral fill or unfilled. Thicknesses range from 6 to 750 micrometers. The standard width is 610 millimeters, and some of the films are available in widths to 1.5 meters.

The company said the amorphous film is typically used in thin-gauge thermoforming. When it is heated above the glass transition temperature for PEEK, 143°C, it will revert to semicrystalline form.

According to Victrex, the mineral-filled film is useful for applications that require a higher modulus or lower coefficient of thermal expansion than the unfilled films have.

The company has published a long list of virtues of the films, which we won't try to reproduce here.

First on the list is high heat resistance. According to Victrex, films 25 to 125 mm thick have a UL RTI rating of 220°C for mechanical use without impact and 200°C for electrical use. They can hold up under lead-free solder processing temperatures of 300°C. PEEK resists a broad range of chemicals—including acids, salts, hydrocarbons, and steam. PEEK film also resists moisture.

According to John Getz, the global commercial leader for Aptiv films, because of the light weight of the thinnest film and PEEK's moisture resistance, a manufacturer has decided to use it as the vapor barrier in aircraft insulation. This is the 6 mm thickness, which one observer compared to plastic wrap. Aptiv film also has found its way into a high-performance tweeter for a loudspeaker.

High pitch: Applications for a new polymer film include the tweeter for a loudspeaker.

The company has outfitted a factory to produce the various films at its complex in Thornton Cleveleys in the northwest of England. Victrex says it has put more than 5 million pounds, or $10 million, into the facility. The plant is a white-coat area designed with smooth surfaces and flush lighting to maintain a high level of industrial cleanliness. Victrex says its Aptiv films are certified for food contact and medical use.

Mike Percy, films global technology manager at Victrex, pointed out that the plant and its extruding equipment are dedicated to producing PEEK films. As a result, the company avoids the risk of cross-contamination of the polymer.

Victrex says the film is versatile. It can be coated with copper, for instance, for use in radio frequency identification tags. Covalence Adhesives, a manufacturer in Franklin, Mass., is using the PEEK film for a line of tapes with a silicone adhesive. Among recommended applications for the tape are down-hole repairs in oil fields.

Victrex has also opened what the company calls an applied technology center at Thornton Cleveleys. The center is an expansion of the company's facilities that work with customers on product development. The center, which cost about 1.5 million pounds, contains extrusion and compounding equipment and injection molding machinery. It will provide material specification and testing services.

From simple linear and pick-and-pack systems to gantries and booms, Cartesian robots are increasingly common in assembly and production environments. Vendors have come a long way in providing off-the-shelf solutions. Yet most Cartesian systems require at least some customization. At worst, they require users to mix and match components from several vendors and fabricate custom interfaces from scratch.

Bosch Rexroth Corp. designed its new camoLINE Cartesian motion system to resolve that problem. "We systematically engineered and readjusted every part of the system, from brackets and modules to electric motors and pneumatic grippers to work together," said Bashar Abdo, Cartesian robotics product manager at Bosch Rexroth.

Robot at work: This simplified system can handle jobs like pick-and-place, stacking, and palletizing.

"Engineers who want to build a robot don't have to do any design. They just select the parts they want and put them together using standardized connectors and interfaces."

Abdo calls the system "a full line of pre-engineered electromechanical and pneumatic robotic Erector Set parts."

This starts with the system's aluminum profiles. Each has two rows of centering holes with standardized spacing. Every component and connection element has the same hole spacing. This makes it easy to put together entire systems with no additional alignment.

Users can choose from a range of electromechanical and pneumatic components for the robot's business end. The linear motion modules come with a choice of accurate ball screw drives or fast toothed belt drives. They accept Rexroth IndraDyn servomotors, whose absolute encoders remember their position after shutdown and eliminate the need for referencing cycles upon power-up. The pneumatic actuators include rotary modules and parallel, angular, and radial grippers.

Erector Set: Bosch Rexroth has developed a design of standardized parts and simplified software for Cartesian robotic systems.

The software is perhaps the most innovative part of the system. "You don't have to write any ladder logic or do any programming," Abdo explained. "We've taken existing robotic programs and isolated their motion handling components. You can do the point-to-point handling and simple assembly in 10 minutes by scrolling down a menu in the controller."

Such simplified design comes with a cost. "The software lets engineers program simple handling and assembly jobs," said Abdo. "It moves product, does pick-and-place, stacks, unstacks, palletizes, locates parts on a tray, and does simple assembly. If you want to dispense fluid following a very accurate path, you'll need to do real programming."

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