Specific Advantages of Hydroforming

Inexpensive Tooling: A male die (punch) and a draw ring (blank holder) are generally the only tools required. The rubber diaphragm in the Hydroform machine acts as a universal female die. Hydroform tools normally cost at least 50% less than conventional press tooling.
Versatility in Forming Complex Shapes and Contours: Irregularly contoured shapes are easily formed using the Hydroform process because matching dies are not required.
Minimal Material Thinout: Hydroforming flows the metal rather than stretching it. Therefore, material thinout is minimal -- usually less than 10%. Wall thickness at the open end of the part is typically nominal or greater (a big advantage for trimming, welding and assembly). This often results in material savings because thinner blanks can be used -- a particularly important factor when expensive alloys or a large number of parts are ordered.
Fewer Operations Required: Many parts requiring two or three operations on conventional presses can be formed in one Hydroform operation. First draw operations are frequently Hydroformed with reductions of 60% to 70% -- compared to only 35% to 45% using conventional dies.
Savings in Tool Materials: Hardened tool steels are rarely required. Most punches and draw rings are made of meehanite (cast iron) -- an inexpensive, easily machined material that provides an exceptionally long tool life. Kirksite and cast plastics may be used for very short runs.
Fast Tool Changes: Tools are quickly mounted and are self-centering and self-aligning. Setups are quick and simple.
Savings in Finishing Costs: Matched die methods of forming can cause scuff marks, shock and stretch lines. In the Hydroform method, the wrapping action of the flexible diaphragm virtually eliminates these faults. Savings of up to 90% in finishing costs have been realized.
Materials Versatility: Practically all sheet metals capable of being cold formed -- carbon steel, aluminum, stainless steel, copper, brass, precious metals, high strength alloys, and others -- can be Hydroformed. Thickness of materials can vary within the limits of the machine without need for tool revisions.
Precision: The Hydroform method forms parts with extremely difficult configurations while at the same time working to precise tolerances.
Ease of Design Change: Development cost can be a large part of tooling cost with conventional deep draw techniques. With Hydroforming, material or metal thickness can be altered usually without any tooling change being necessary. Hydroforming can also eliminate or minimize the number of multiple draw operations required, with a corresponding reduction in tryout costs.
Low Work-Hardening: Hydroforming does not cause work-hardening of material at the same rate as conventional drawing operations. Consequently, annealing between draw operations is rarely required. The need for multiple draw operations can often be eliminated, too.