Notching Rather than Cutting

A new vinyl window manufacturing system seeks to create "true one-piece flow."
June 1, 2008
FEATURE ARTICLE | Operations

Most companies making vinyl windows follow the same basic manufacturing steps as 35 years ago. Lineals are optimized and cut into lengths. When the welding station operator is ready to assemble a particular unit, all four pieces are located and loaded one piece at a time into a welder. Sash and frames are then welded, cleaned and sent to glazing. There have been improvements to the process over the years, but most changes have been minor, according to Frank LaSusa.

A manufacturer of building products, as well as a consultant involved in analyzing manufacturing and material handling operations in numerous industries, LaSusa first observed the vinyl window manufacturing process about 12 years ago-and was taken aback. He saw intensive manual labor and work force requirements, error prone processes, excessive work-in-process material handling and enormous amounts of waste. He thought the process could be drastically improved.

"The assumable waste was unimaginable," LaSusa asserts. "The drops were even worse. A single lineal would be handled as many as 15 times through the fabrication process. Why cut the vinyl apart? Why have all those people handling it? Why use all that space? Why stage what could be kept as one piece?"

With the new process, vinyl lneals are notched rather than cut. The four sides of a vinyl sash or frame are kept together. Atrium uses a special corner piece where the nail fin has been removed in the notching process.

His solution was to create "true one-piece flow." Instead of cutting lineals, they are notched. The four sides of the rectangle are kept as a single piece to be loaded into a welder. Today, LaSusa is far beyond the idea stage. His first Notch Above production line is in use at Atrium Windows & Doors, a vinyl and aluminum products manufacturer with plants throughout the country. Gary Hoffman, director of operations for Atrium's West Region, says Atrium tested the first Notch Above line for two years before placing it into production. Since that time, the company has seen the promised scrap, operator savings and throughput, he continues, leading to the decision to order two more lines.

Getting to this stage with the concept has taken multiple prototypes, five patents, $6 million and more than a decade of long work weeks, LaSusa reports. In getting started, he notes, his first goal was to bring in alliance partners with experience in fenestration and related fields. Paul Warner, one-time CEO of Mikron Industries, recognized the future of the technology and offered funding for Vinyl Link, the company started to develop his ideas into products, LaSusa reports. The company is based in Layton, Utah, where LaSusa also owns Vinyl Life Outdoor Building Products, which has just started offering a program to supply pre-notched profiles to window manufacturers ready for welding.

Another early partner was FeneTech, the provider of window and door company software. Ron Crowl, president, recognized the potential benefits of the system, and as a result the company committed substantial resources to develop NotchWare-proprietary software integrated into the Notch Above production system.

Atrium's interest in the concept grew out of its "ongoing quest to improve its manufacturing processes," reports Chris Reilly, director of marketing communications and replacement programs for the Dallas-based manufacturer. "Better cost containment and improved product technology as a result of the Vinyl Link system fit within that mission."

PRE-OPTIMIZED LINEALS

The system uses standard vinyl window and door lineals. Unlike with existing manufacturing operations, however, "lineals are pre-optimized and always presented in the schedule order," says LaSusa. In order to deliver the best yield possible, he explains, Vinyl Link studies 90 days of a customer's peak production period lineal usage from the current or preceding year. This is used to estimate the most beneficial lengths and SKU's to achieve optimum inventory yield. "As result, you basically eliminate drops."

Lineals are loaded into the company's notching equipment, where they are notched rather than cut through completely. All four sides of a window sash or frame-three sides in the case of frames incorporating a sloped sill-remain connected until they get to the welder. At the welding stage, the operator loads the one notched piece (one notched, and a separate sloped sill for those frame types) into the company's Triple Play machinery, which shears the corners and squares the notches before welding. "Lineals are always in order, you never weld out of configuration and practically your only scrap is the notch cut," LaSusa claims. Other benefits of the equipment include greatly reduced material handling and floor space requirements, he notes.

A notched profile gets loaded into a specially modified welder at Atrium's plant.

Vinyl Link's welders used at Atrium are based on modified equipment from Sturtz Machinery Inc. Creating a welding system that could shear, square and seal the already notched corners of the single-piece lineal was one of the biggest challenges in developing the process, LaSusa reports. As an early adopter, Atrium provided input on design changes in the Triple Play corner joinery system, he adds.

Vinyl Link has developed the technology to the point that cycle times are now less than 60 seconds for a frame or sash, it reports. Adding a second welder to a line cuts cycle times in half to 30 seconds and allows two operators to produce 1,100 frames and sash per shift, the company reports.

For the window Atrium manufactures on its Notch Above line, the manufacturer stocks just three lineal profiles. A single operator runs the sash line, which has one welder. "We're saving four people over our other lines," Atrium's Hoffman reports. "And we are getting it done in less space, 25 feet by 125 (feet). The line can be set up in a Z, U or straight, depending on your space constraints." The company tested Notch Above in California before moving the line to Phoenix for production. With the consolidation of manufacturing operations announced in April, the line will go back to California.

The new manufacturing approach does not change the finished window in any way, Reilly points out. "The process is more efficient and offers a better way to manufacture, providing the customer with a high-quality product," he states. "Specifically, the Vinyl Link process allows Atrium to reduce waste and scrap, and improve yield per lineal, while maintaining the same level of product integrity and functionality that we demand."

LaSusa says the system can deliver significant reductions in costs per window from many factors. The labor savings alone are 50 to 75 percent per unit, he estimates. "You're reducing labor and annual capital expenditures while increasing capacity. You can improve quality and lead times. You can reduce inventory and increase inventory turns."

The reduction in assumable waste in pie cuts can save up to $1.25 to $1.30 per window on the frame alone, according to LaSusa, who says overall raw material purchases can be reduced up to 30 percent annually, "which in itself is an incredible savings."

Before putting the Vinyl Link system ino production, Atrium woked with the supplier to develop and reine the manufacturign equipment, including the notching machinery, for the pst two years.

The company's system works with any current vinyl profile, and LaSusa sees even greater advantages for custom sized window manufacturers less able to take advantage of multi-stack welding in their production. For the future, he notes, Vinyl Link is also developing techniques and equipment for fiberglass and resin composites. LaSusa also reports that the company has patents on sonic welding and adhesive applications in corner joinery, with plans to develop and test these technologies going forward.

In the meantime, LaSusa asserts that the new approach already has clear advantages. "As of today, no one can process an entire window in less time than a Notch Above System, which is between 25 and 30 seconds at capacity." With the development stage complete at Atrium, Vinyl Link is now ready to show other window and door manufacturers its capabilities. And despite the market, LaSusa suggests it's the "perfect time" for the launch of the new system. "People are trying to find ways to save money. They know have to get the most they can out of their equipment."

Asked whether he expects other manufacturers to follow Atrium in using the new system, Reilly says, "Innovative technology is a result of competition and something manufacturers are always striving for. Any process that can provide a competitive edge or technological advancement is always likely to be adapted."

In the meantime, he concludes, "We are excited to be on the leading edge of this technology and look forward to expanding this process in additional Atrium facilities in the future. Our Series 6000 product families out of California and Colorado will give our customers a first-hand experience with this innovative window system."