An Introduction to Stretch Forming Aluminum

06/05/2018

At St. Cloud Window, we specialize in historic window replicas and landmark preservation. Manufacturing windows for buildings that were designed during different eras present specific challenges. So how does stretch forming aluminum help us install modern windows in these historic buildings? To answer this question, we’ll provide an overview of stretch forming aluminum, as detailed in a recent article on the Linetec blog.

Fitting unconventional windows

When installing windows into a historic or unique building, the windows often must be fitted to curved, arched, or unconventional openings. This requires that the aluminum frame is stretch formed for a custom, tight fit.

Creating the desired shape

Stretch forming aluminum is the process of shaping aluminum sheets into contoured curves with the ability to stretch and bend. In order to produce the desired shape, the aluminum material is wrapped around a form while being held under constant tension. This forms precise dimensions and specific contours while limiting wrinkling and gaps.

Stretch forming allows for aluminum to be shaped into curves and arches of different sizes and shapes, with arc lengths varying to fit the window opening. The aluminum frame can be finished in paint or anodized.

Improving thermal performance

The frame can also be thermally improved in order to reduce the amount of heat transfer through the window and frame. By finishing the frame and installing the thermal barrier after the aluminum has been stretch formed and shaped, the amount of stress on the barrier is reduced and performance is improved.