How To Hydroform Sheet Metal

Fluid or oil is pumped into a chamber behind the rubber diaphragm causing the metal to draw until it reaches the shape of the mandrel.

How to hydroform sheet metal. Hydroforming is a process in which the sheet metal is forced to take the shape of only a single rigid die by the action of fluid pressure which acts through a rubber diaphragm. The metal is formed quickly and can be removed once it has taken shape. The hydraulic oil or fluid is pumped into the chamber behind a rubber diaphragm that is the counter pressure to the rising mandrel. The resulting near net shape parts have a smooth surface finish and require no secondary operations.

The press is closed bringing the chamber of oil down on top of the blank. The kicker with this build is that there is no fluid at least not until the 40 000 pound hydraulic press semi liquifies the thick neoprene rubber pad placed over the sheet metal blank and die. The hydroforming process begins by placing a metal blank on the ring. The forming chamber is pressurized with oil while the punch is raised through the ring and into the the forming chamber.

As part of this process a flat metal disc is placed on to a mechanically driven mandrel. Concave shapes can be created with this process but may require secondary finishing.