Hydroform

From Free net encyclopedia

'Hydroforming or hydramolding is a specialized type of die forming that uses a high pressure hydraulic fluid to press room temperature working material into a die. The working material, usually metal, might be in the form of a tube, with the high pressure fluid inside the tube and the die outside the tube, or a sheet, with the fluid on one side and the die on the other. Hydroforming allows complex shapes with concavities to be formed, which would be difficult or impossible with standard solid die stamping. Hydroformed parts can often be made with a higher stiffness to weight ratio and at a lower per unit cost than traditional stamped or stamped and welded parts. One of the largest applications of hydroforming is the automotive industry, which makes use of the complex shapes possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for vehicles.

This process is based on the 1950s patent by Milton Garvin of the Schaible Company. It was originally used in producing kitchen spouts. This was done because in addition to the strengthening of the metal as detailed above, Hydramolding also produced less "grainy" parts, allowing for easier metal finishing.

Industrial hydroforming machines use a piston to generate pressure in the hydraulic fluid used in hydroforming, but an experimental alternative is the use of explosives to generate the pressure. Called explosive hydroforming, this method places an explosive charge, with or without an additional working fluid, on the high pressure side of the material. When the explosive is detonated, the pressure forces the working material into the die, at pressures of up to millions of pounds per square inch. See also explosive welding, which allows metals of different types to be bonded at an atomic level. Since both explosive hydroforming and explosive welding use similar techniques, it is possible to combine the two methods to both shape and weld metals simultaneously.