And it promises to get even bigger. General Motors' bet on hydroformed, laser-cut rails for the Chevy Silverado and GMC Sierra pickups has paid off smartly. According to Frank Brennan, every major automotive frame supplier is working on hydroforming projects and he indicates that programs in the works are likely to result in orders of some 200 lasers by the fourth quarter of 1999. The benefits of hydroforming, especially as compared with traditional fabricating methods, are multiple. Not only are part counts slashed, but time, material, and operators are all reduced, as well, as welding individual pieces gives way to forming tubes.
Hydroformed rails require an assortment of holes, slots, and other openings.
Fundamentally, there are two ways that these can be produced. One is via hydropiecercing. It requires fixed tooling. The other method is to use a laser. Because of the nature of the hydroformed rail cutting operation, which necessitates moving up and down along the curved tube, a robot-laser combination is the norm.