Volume 33, Number 5, May 1998


Vertical IG Assembly Optimizes Space

by Jim Plavecsky

With a national unemployment level at its lowest point in years, many manufacturing companies are experiencing labor shortages. Wages are rising in manufacturing as service-sector competition for valuable manpower intensifies. Floor space can also be a problem as many wood and aluminum window manufacturers diversify, adding vinyl windows to their product lines due to their ever-increasing popularity. One solution to the manpower issue that also most effectively uses available space is vertical automation for insulating glass.Insulating glass (IG) production historically has been a labor-intensive operation involving many separate steps such as spacer cutting, desiccant filling, frame assembly, sealant extrusion and/or gunning, and in some cases, oven-curing. Using vertical automation set up in stages, an IG manufacturer can utilize a building-block approach to minimize manpower and space requirements while allowing for future expansion as production requirements grow.

Vertical Systems

The unique thing about a vertical system is that when production requirements do grow, the IG manufacturer can double his maximum output without doubling manpower requirements. This is accomplished by placing two vertical lines side by side in a mirror-image fashion. One line runs from left to right while the mirror-image line runs right to left. Because the lines are automated, operators can be placed between the two lines and effectively perform their tasks in duplicate on both lines. This means doubling the output without doubling the manpower. For example, Willian Ltd. of the UK has just introduced a vertical line for production of dual-seal insulating glass using Edgetech's Super Spacer® product. As shown from left to right in Illustration 1, the line includes a vertical rack, glass washer, an inspection rack, a tilt application station, muntin installation station and an automatic assembly station. Sealant application is then accomplished by integrating an automatic vertical gunning station supplied by either Spadix or Lenhardt.

Such a line is capable of producing 600 IG units in an eight-hour shift with only three operators (four if installing grids). The operators perform the following tasks:

The line itself takes up an area less than 100 feet long by 20 feet wide.

Building-Block Approach

Now, if the IG manufacturer wishes to double production, a second tilt-application station can be added, in series, to expand the production capability to 1,000 units per shift with the addition of only one applicator. This line is shown in Illustration 2.

But what if we needed to increase our production to 2,000 units per shift? Another way of expanding our original line is to install a second, mirror-image line in parallel. This line, shown in Illustration 3, doubles the output of the original line while employing only one additional operator.

By combining equipment and operators both in series and parallel fashion, we can assemble the line shown in Illustration 4, capable of producing as many as 2,000 dual-seal IG units in an eight-hour shift.


Vertical production systems have been popular in Europe for years, mainly as a result of limited space availability. In North America, however, space and manpower have, for years, been relatively abundant. Therefore horizontal production systems have proliferated here for residential glass, with vertical systems being used mainly for commercial glass where larger lites of glass lend themselves well to vertical handling equipment.

Today, with manpower often in short supply, North American IG manufacturers have reason to give vertical systems a second look—even if space is not necessarily a concern. Vertical systems put glass and frame systems at eye-level, allowing operators to quickly inspect glass and install grid assemblies. Vertical systems also facilitate cost-effective layouts where operators can be placed between two parallel production lines to share the operating duties across lines. This maximizes the use of manpower employed and optimizes the productivity of the IG production line.

USG Jim Plavecsky is director of business development at Edgetech I.G. in Cambridge, OH. He has worked in the industry for more than a decade.

© Copyright 1998 Key Communications, Inc. All rights reserved. No reproduction of any type without expressed written permission.