Agility, economy, and speed drive today's assembly technology, as demand for customization and quickly shifting consumer appetites make the battle for profitability ever more complex. Explains Ray Gottsleben, vp sales & marketing at Arlink Workstation Systems: "Uncertainty is increasing in all aspects of manufacturing: uncertainty in the number and types of products to be manufactured, uncertainty in the quantities or lot sizes of the build, uncertainty concerning the processes that will be used to assemble, and even uncertainty as to where the products will be manufactured.... Accordingly, the assembly equipment and assembly processes utilized need to be flexible and agile enough to quickly respond to the need for change." (For more, click here.)

"The key issue is always time to market," notes Kevin Gingerich, marketing services manager, Linear Motion and Assembly Technologies at Bosch Rexroth Corp. "Innovations must get to the customer as quickly as possible. We can offer customers great products, but the secret to success is really the optimum deployment of those technologies." (Bosch Rexroth designs its conveyors, illustrated in the photo, with pre-engineered modules so systems can be moved, reconfigured, or expanded. Binary and RF coding systems allow multiple product runs on a single line.) (For more, click here.)

And responsibilities are shifting, according to Paul A. Gustafson, president of Emhart Fastening Teknologies and executive vp of Black & Decker Corp. "Increasingly [manufacturers are] looking to us to do the fastener design and the assembly; they see the value added from their point of view in product design and marketing," Gustafson tells IEN's Mary O'Hara Smith. "We basically are becoming the specifiers." (For more, click here.)

Manufacturers require greater flexibility, states Douglas Burns, director of Rockwell Automation's Global OEM Program. "Customers need to be able to quickly change assembly configurations and provide systems that can build down to a lot size of one," he says. "Order customization is increasing in frequency, and all the while product shipping time is decreasing," adds Tom Wolff, manager of business development at Rockwell. (For more, click here.)

"Assembly products that use a T-slotted aluminum profile as the main structural element can be reconfigured on the fly to recreate assembly systems quickly and easily -- a requirement in lean and many other assembly applications," Gingerich points out. "Flexibility never goes out of style, and our customers are basically reinventing their production systems all the time."

The assembly sector also faces technical and environmental challenges, notes Christine Salerni, medical market manager/OEM Industrial at Loctite Corp. "The use of solvent welding for component assembly has become both a mechanical and environmental issue," she explains. "Ozone-depleting chemicals have often been replaced by flammable, more harmful alternatives that are now causing designers to seek other options. In addition, solvent welding cannot be used effectively on thermoset plastics and is more likely to cause stress cracking of components versus other liquid joining methods. Solvent bonding/welding is also not capable of securing joints with large induced gaps." As a result, the industry has adopted "solvent-free adhesive systems as a primary means of assembly," says Salerni.

This technology provides advantages beyond answering environmental and safety concerns. Solvent-free adhesives "can be used with dissimilar materials such as metal and glass," Salerni points out. They can also bond thermoset materials and reduce the chance of stress cracking. "Adhesives have a much less critical open time," adds Salerni, noting that the "time between application of the solvent and joining the parts is critical; joints become weak if too much solvent remains in the bond area or if too much solvent has flashed off prior to assembly." Additionally, they "distribute stress loads across the entire joint," and dispensing "can be easily automated." (For more, click here.)

Cost containment remains a key goal, adds Jay McKenna, special products manager at PEM Fastening Systems, who notes that "every self-clinching fastener is developed with a simple idea in mind: less is better. These types of fasteners provide strong, permanent threads in metal sheets too thin to tap and can serve as reliable alternatives to extruded or stamped threads. [And] they usually require fewer parts and fewer assembly operations than some other types of fastening hardware." (For more, click here.)

Emhart "took an electronics approach" to self-piercing riveting, Gustafson observes, "so rather than the typical large bulky hydraulic system that's used to drive in and power these things, we took an approach with servomotors," building in such features as self-regulating feedback loops "so quality can also be controlled and reported on live from the production line." Emhart has grown "from a basic penny part supplier to a fairly broadly based assembly systems supplier," Gustafson tells IEN, with 80% of its product revenue coming from systems.

Adds Don Harris of Bimba Manufacturing: "Pneumatics have been in use for a long time [but] are not often considered in a positioning application because of their inherent physics. However, depending upon the accuracies [and] repeatability required, ±0.005 in. can now be achieved" using pneumatic control systems such as Bimba's PCS. "Being able to control the rod or rotary position of a pneumatic cylinder, via feedback signals with or without a position control system, addresses low-cost solution concerns, combining low-tech components as part of a high-tech assembly and use of traditional parts common to the enterprise." (For more, click here.)

According to Peter Timpanelli, director, Global Sales at Atlas Engineering: "For those instances where there is access from only one side, so-called 'blind' applications, threaded rivet nuts...can provide a practical and effective solution... With inaccessibility no longer an obstacle, aluminum, brass, steel, or stainless steel threaded rivet nuts [are appropriate in] tubing, extrusion, and other similar types of applications." Additionally, installation does not require "product-dedicated assembly locations." (For more, click here.)

Emhart handles many hybrid materials "that are softer to deal with," according to Gustafson, as well as "fairly sophisticated alloys." Along with composite plastics and a myriad of combinations, "that really makes the fastening job much more difficult." As to equipment, the switch from handheld to automatic feeders has resulted in a "significant transfer between labor and capital," says Gustafson. And at Emhart's German labs, "40% of our R & D budget was spent on software" in 2001.

Wolff expresses surprise at "how few installations utilize communications to extract production data from the factory floor....There are a number of cost effective software applications that can very easily drive information to floor operators and the companies' business systems."

Today's assembly sector often combines manual operations and advanced technology. "In a large assembly system, you may even have manual assembly or lean manufacturing cells feeding subassemblies to automated conveyor systems, or automated conveyor systems feeding subassemblies to manual assembly stations," according to Gingerich.

Emhart takes a nuanced approach. "I don't think you take a hammer out of someone's hand and hand them a $150,000 microchip controlled, robotic-armed nailing machine," Gustafson comments. "There's an intermediate step." For example, by switching an operator from a handheld riveter to one "that's suspended from an arm to take some of the stress off the operator," and attaching an automatic feeding device, productivity can jump "by maybe 30-40%," Gustafson notes.

Budget-conscious manufacturers could consider semi-automatic packaging systems to upgrade manual operations, comments Avery Dennison Fastener Div marketing manager John Earley. "With these systems, the actual fastening is done automatically, but an operator is needed to correctly position the product and packaging and to activate the fastening system." Avery Dennison's Elastic Staple variable needle system inserts strong, pliable fasteners around targeted products, attaching them securely to cardboard or other packaging materials. (For more, click here.)

What developments are in store? "You'll see innovations aimed at enhancing the speed with which manufacturers can deploy new equipment," Gingerich predicts. "This means easier to use software interfaces for robot controls, it means preassembled linear motion systems, it means individual suppliers offering greater combinations of complementary products to simplify the supply chain."

Burns believes that "distributed control is gaining momentum in the marketplace. By pushing more control closer to the machine, programming becomes simpler and takes less time to integrate." And according to Wolff, "Auto configuration on products will become more commonplace. Drives that automatically set up for network operation or autotune based on the motor and connected load will simplify engineers' projects."

Users can expect "resins with indicators built in to respond to vision systems," notes Clai Bachmann, senior vp of marketing communications at Dymax Corp. One ultrahigh-intensity spot wand-style lamp now offers the option of up to 4 UV curing stations. With an intensity of 40+ W/cm², BlueWave 200 makes multiple wand cures feasible.

"Future product offerings will likely include longer elastic fasteners and fasteners with greater tensile strength," Earley adds. "These fasteners will be capable of attaching larger and heavier products than currently possible."

Wireless technology can be used in "modular installations where the installation is very controlled," suggests Wolff. "Individual subsystems will be close coupled through wireless technology and the cost effectiveness will be realized in the simpler reconfiguration capability of wireless."

Bosch Rexroth expects the Web to "develop into much more" than a research or commerce tool. "Digital cameras, webcams, computer renderings in 3D, the new 3D printers -- all of these are highly used today and will continue to shrink the distance between the assembler, his suppliers, and his customers," Gingerich contends. "These people will interact in real-time on the Web as bandwidth grows, laying out entire assembly systems and even viewing simulations of their future operation online."

Emhart has a "whole crew of people around the world whose only job is to perform and to implement technologies that will allow for instant communication around the world," says Gustafson. "We do live design between, say, Japan and the US, say for Honda," he adds. "We now have systems we launched this year where the BMW welders at their plant in South Carolina are controlled from a computer in Germany. And one of the biggest problems in welding is setting up the parameters....We now supply systems that, first of all, are self-regulating and so they will adjust automatically to changing conditions, and secondly, via the Internet, they can set the parameters from any point in the world."

According to Burns, "in assembly we are at full stride implementing lean control architectures with integrated logic/motion and distributed I/O." And Wolff cautions: "OEMs that are not providing lean, flexible systems are being priced out of the market....Now that control and information systems are highly distributed and provide increased information, lean and flexible is growing at a rapid rate."

Industry has entered the age of flexibility, Gingerich believes. "Assembly products designed to be flexible can be added to almost any manufacturing environment. Our new SR4 turboscara robot, for example, can be mounted to a ceiling or wall to add robotic precision to tight spaces....In short, with products that are designed to give manufacturers every option for efficiency, it becomes the deployment and mixing of the appropriate technologies that makes the difference, not the technologies themselves."