Manufacturers strive to integrate assembly and packaging lines.

"East is East, and West is West, and never the twain shall meet," wrote famous English novelist Rudyard Kipling in the late 1890s. Although he was referring to culture, customs and geography, Kipling could just as easily have been talking about assembly lines and packaging lines.

Traditionally, assembly and packaging have been treated separately by engineers, machine builders and systems integrators. However, the lines of distinction are starting to blur. More and more manufacturers are integrating their assembly lines with blister packers, cartoners, case packers, fillers, palletizers, sealers, wrappers and other types of packaging machines.

Indeed, according to the 2005 ASSEMBLY magazine capital spending study, production engineers are beginning to pay more attention to packaging. Out of 28 different equipment categories that respondents plan to invest in this year, packaging ranks fourth. Only workstations, screwdrivers and software are rated as higher priorities.

Most manufacturing engineers associate packaging with electronics, pharmaceuticals, food and beverage, medical devices, cosmetics and personal products. But, consumer goods manufacturers also depend heavily on packaging applications. Indeed, batteries, flashlights, hardware, light bulbs, padlocks, pens, razors, sporting goods, toothbrushes, toys and other products require a wide variety of blister packs and other types of packaging.

To cut costs and reduce time to market, packaging is becoming a more critical downstream link with automated assembly systems. Most observers believe that makes perfect sense, because, in many respects, packaging is like a cousin to assembly. Indeed, the two disciplines share many similarities. While the challenges are different, the goals remain closely aligned: eliminate waste, reduce cost, and improve time to market.

"There are more similarities than differences between assembly and packaging," says Dave Schuh, vice president of sales and marketing at MGS Machine Corp. (Maple Grove, MN). "Perhaps the main difference is assembly designs are usually highly customized for the application, whereas a greater portion of packaging machines typically starts from a base design which then is customized for the application."

Assembly machines and packaging equipment use similar technology, such as controls, drives, sensors, servos and software. Both systems use similar parts-marking or labeling technology. Machine vision technology is also commonly applied to both processes. In addition, adhesive and ultrasonic welding are used to assemble products and to close and seal boxes, cartons, pouches and flexible packages.

"In either assembly or packaging, it is critical to minimize and, if possible, eliminate opportunities for production stoppages or delays," notes Tony Barr, product marketing manager for modular conveyor systems at Bosch Rexroth Corp. (Buchanan, MI). "The fundamental issues and challenges are the same-both sides are trying to maximize production flow and minimize bottlenecks.

"Process steps in packaging would include labeling, capping, cartoning and wrapping," adds Barr. "In assembly, it might include [robots] or pressing devices. The machines associated with these process steps typically have fixed operating characteristics. There's a great deal of crossover between assembly and packaging."

Of course, there are also fundamental differences between the assembly process and the packaging process. For instance, most packaging functions are performed dynamically-while the product or part is moving. In sharp contrast, most assembly functions are performed with the product or part stationary.

Another key difference between the two processes is nominal line speed. Packaging processes generally tend to have higher line speeds. "Packaging machines typically run faster," says Russ Lauer, vice president and general manager of the plastics and small part automation division of Acro Automation Systems Inc. (Milwaukee). "Because they rely on continuous motion, packaging lines can be four or five times faster than assembly lines. Most packaging machines don't index or stop like assembly machines. And, part tolerances are much more relaxed compared to assembly lines."

In addition, line changes are made more frequently with packaging equipment, often with very little lead time. "As assembly functions and packaging functions are merged into a single value chain, however, this distinction will diminish in relevance," notes Barr. "Such process characteristics as flexibility-which is routinely associated with brand-driven, contemporary packaging operations-will emerge as both a strategic and operational driver in the assembled consumer goods sector."

Packaging Primer

Thousands of different types of packaging styles and configurations exist. But, there are two basic types of packaging: primary packaging and secondary packaging.

Primary packaging refers to packaging that immediately envelopes a product. It provides most of the strength and the moisture, vapor or grease barrier needed to safeguard a product's purity, potency and integrity from the time it leaves the assembly line until it's used by the consumer. Examples of primary packaging include blister packs, clamshells and trays.

Secondary packaging is the outer package into which the primary package is placed. Its major function is to protect the product during shipping and distribution. Examples of secondary packaging include cartons, containers and pallets.

Primary packaging machines and second packaging equipment are often seamlessly integrated to form an automated packaging line.

Blister packs, clamshells and trays are three of the most popular types of packaging.

A blister is a thermoformed cavity in plastic that is then sealed to an insert card with a product in between. Blister packs are a cost-effective packaging solution that allows a product to be clearly seen, but not touched, as it hangs on a retail shelf.

A clamshell is a rigid thermoformed plastic container that features a hinged lid with a positive snap closure so the package can be opened and resealed. An insert card is included to explain the uses and features of the product.

A tray is a multicavity package thermoformed from plastic that holds numerous parts or products. Trays are often used as standalone retail-store displays.

There are numerous types of packaging machines. But, basic categories include:

  • Filling machines-devices that measure a predetermined volume, weight or number of product and fill it into a bag, bottle, box, container, sack, tube or other type of package.
  • Closing machines-devices that seal or close filled packages by crimping, folding or tucking. Adhesives, gummed tape and ultrasonic welding are often used, in addition to heat sealing.
  • Cartoning machines-devices that erect and close carton blanks or folded and side-seam sealed cartons.
  • Wrapping machines-devices that wrap a flexible material, such as plastic film, around a product or group of products.
  • Pallet forming machines-devices that form, dismantle or secure pallets and other loading units.

Some packaging equipment performs multiple functions. For instance, a thermoform, fill and seal machine starts with a web of deformable material that is heated and formed with pressure or vacuum; filled with product; sealed with a top film or magazine-fed lid; and then cut to produce individual blister packs.

"There are many more different types of packaging machines than assembly machines," notes Acro's Lauer. For instance, there are more than 50 types of wrappers. "While there are many standard types of machines, packaging machine builders tend to specialize and make a specific type of machine or product for unique applications." As a result, systems integrators play a key role in taking various pieces of equipment and connecting them to run as smoothly as possible.

Most packaging machines today are flexible. They feature modular configurations and layouts to maximize application flexibility and minimize reconfiguration time. That enables manufacturers to change package formats faster to meet market requirements. In addition, more and more packaging machines use servo motion control.

Packaging Industry Trends

Packaging is a huge industry. Indeed, consumer and industrial goods manufacturers in the United States spend more than $5 billion annually on packaging equipment.

"Companies are constantly looking to gain a competitive edge," says Chuck Yuska, president of the Packaging Machinery Manufacturers Institute (PMMI, Arlington, VA). "They want packaging equipment that decreases downtime, but still delivers enough flexibility to help them put the newest and most innovative products on the shelves, which means new machines will continue to be in high demand."

After several sluggish years, U.S. packaging machinery shipments will exceed $5.2 billion this year, Yuska predicts. And, he expects that growth to continue in 2006, with shipments hitting $5.5 billion.

Consumer goods manufacturers are investing in many different types of packaging equipment, but some of the leading machinery categories in 2005 include coding, dating, printing, marking, stamping and imprinting machines (7.1 percent growth); labeling machines (6.9 percent); shrink film and heat-sealing machines (4 percent); conveying, feeding, orienting, placing and related machines (3.4 percent); and skin-blister-packaging machines (2.4 percent).

According to Yuska, the top three reasons that manufacturers order new packaging equipment are:

  • To replace machinery to gain efficiency, speed, flexibility and productivity.
  • To expand production capacity for existing products.
  • To add automated machinery to reduce labor costs.

"End users are operating an increasing number of packaging runs [because of] the proliferation of product varieties, product sizes and product configurations that packagers must handle on the same packaging lines," says Yuska. "[Consumers] are demanding a greater variety of product sizes and packages, so [manufacturers] are looking for machinery that is easy and quick to change over. The need for greater flexibility to handle the dissimilarities, as well as to speed changeovers, is growing rapidly."

Giant retailers have had a huge effect on the kind of packaging that manufacturers must provide today. Indeed, companies such as Costco Wholesale Corp. (Issaquah, WA), Home Depot Inc. (Atlanta), Kmart Corp. (Troy, MI), Staples Inc. (Framingham, MA), Target Corp. (Minneapolis) and Wal-Mart Stores Inc. (Bentonville, AR) wield tremendous clout.

In a recent PMMI study, nearly 61 percent of respondents claimed that their major customers, such as super stores, club stores and large chains, both directly and indirectly influence decisions on the need for additional packaging machinery and the kinds of machinery to be ordered.

"The relatively high proportion was generally consistent across most market segments," says Yuska. "Moreover, 48 percent indicated that their customers' influence has increased over the past year."

According to Yuska, there is an ongoing quest to improve product shelf-appeal. "[Those] shifts to alternative package designs, sizes, materials and configurations are having an effect on machinery demand," notes Yuska. "The trend toward multiple sizes and quantities of product in all segments is resulting in orders for new machines because of limitations in the capabilities of existing units."

Seamless Integration

The traditional barrier that once separated assembly and packaging applications is beginning to blur, thanks to new technology and new mindsets. "There's still a separation, but it's diminishing," says Blane Jarchow, a consultant at the Bourton Group (Carmel, IN) who has studied the packaging industry. "In the past, there was a big disconnect between packaging and production. It was common to find packaging engineers huddled in a totally different part of the plant, far away from production engineers. The only time they interfaced was when there was a problem on the plant floor.

"Today, they're still totally different animals, but it makes more sense to do assembly and packaging on the same line," adds Jarchow. "The controls, software and sensors used in assembly machines and packaging machines are very similar. Some assembly integrators are starting to get more involved in packaging."

Paul Beduze, business development manager at Mikron Assembly Technology (Aurora, CO), agrees that packaging is a black science that has traditionally been treated as a separate function. But, when he recently conducted a search of packaging equipment vendors for an application, Beduze was delighted to find many systems that could be integrated with assembly machines. "Most of the integration challenges involved getting parts back and forth via conveyor and getting key operating information back and forth via data synchronization," Beduze points out.

There are numerous advantages to integrating assembly and packaging. For instance, end-to-end systems can save time and money by relieving manufacturers, and their depleted engineering staffs, of the burden involved in coordinating multiple suppliers.

"A lot of our customers want a single source to integrate the whole line," says Beryl Lawrence, sales manager at Southern Engineering & Automation Inc. (Tarpon Springs, FL). "Controls make it a lot easier to integrate assembly and packaging machines. Integrating the entire operation from one control panel makes a lot of sense. It's much more difficult when you have two or more integrators doing it. There's a natural fit for some integrators to do both assembly and packaging."

"We've been doing more and more assembly-packaging line integration work in recent years," adds MGS Machine's Schuh. "It's a trend that is increasing. Customers are more frequently asking their assembly and their packaging integrators ‘will one of you guys step up and take on the full turnkey line integration responsibility?'" According to Schuh, controls-oriented engineers with strong machinery application experience, as opposed to superb mechanical engineers, seem to be best positioned to handle line integration project challenges.

Although it's becoming easier to integrate assembly and packaging, configuring different machines can still be a challenge. "The level of difficulty will vary within different applications," says Howard Speiden, customer dialog section head at Sortimat Technology (Schaumburg, IL). "When a project scope calls for packaging, we typically work with a supplier that specializes in the respective type of machinery."

Speiden agrees that assembly lines and packaging lines are starting to converge. In fact, Sortimat is a first-time exhibitor at this month's Interpack trade show in Dusseldorf, Germany.

"The key to successfully integrating assembly and packaging processes is to involve assembly and packaging experts at the onset of a project," says Speiden. "Obviously, the priority for any designer is to develop a functional product. However, incorporating features for assembly and packaging into the product design will improve performance, quality and decrease costs."

In addition, certain system features will help ensure the success of the project. For example, a nonsynchronous transfer or buffer between the two systems will enable the assembly equipment to supply 100 percent acceptable product to the packaging side.

Typically, conveyors are the critical link between assembly systems and packaging operations. "A conveyor system that offers complete modular flexibility in layout and configuration, while cost-effectively facilitating later expansion or reconfiguration, is vitally important to an integrated [material flow] strategy," claims Bosch Rexroth's Barr.

A conveyor system must accommodate product orientation, accumulation and storage. The key is material flow. For example, if a certain packaging function has characteristics that could cause bottlenecks, accumulation or buffering systems would have to be deployed as part of an overall material flow strategy.