1. Hydroforming uses High pressure fluid to form the part into the desired shape of the die. Two types of hydroforming process: 1.Tube Hydroforming 2.Sheet hydroforming Introduction

2. Tube hydroforming  Used for forming complex shapes  A circular tube is preformed and placed in a closed die  High pressure fluid is introduced into the ends of tube  Application feed thorough ends for uniform thickness  The tube if confied to the shape of the die cavity

3. Hydroforming History 1903: First patent for Hydroforming using molten lead to expand a tube to confirm to shape of the die. Die closing, fluid sealing, pressurization are observed in this patent. 1917: Pre-forming was introduced for improving bent brass tube process. 1932: Patent for making artificial limbs from aluminum tube 1950: Patent for producing hallow metal aircraft propeller using high pressure fluid. 1959: Patent for producing cam shafts by axially feeding material from the ends of tube. 1960: Nippon bulge industries,Japan developed liquid bulge forming process and high pressure sealing methods. Typical application were Bicycle frame joints. 1970:Patent for swaging(end diameter reduction),axial feeding for diameter expansion, Piercing a slot, and in-die end shearing using high pressure fluid.

4. Hydroforming History o 1986:Standard Tube Canada of Woodstock, Canada used Hydroforming technique to produce larger frame members in North America. o 1988-1989:Pressurizing the blank during the die-closing phase of the forming cycle was introduced by Standard Tube. o 1994-1996:Higher expansions through axial end feeding, localized cam forming, and in-die hydrobending Of large auto-frame members. o 1998:General Motors introduces the idea of using multiple, different diameter and thickness for complete – frame Hydroforming in a single die. o Production of more than a million engine cradles per year by hydroforming in the US. o In Europe hydroformed sub-frames are used for models such as Ford’s Mondeo and General Motors’s Vectra. o Chrysler is using 2.8 million hydroformed components per year.

5. Advantages of Hydroforming ULSAB 1995 concluded that a hydroformed intensive body structure(HIBS) would yield.. Reduction in weight of 11% Reduction in Part count of 15% Reduction in cost of 10% Compared with similar size conventional body structure.