Case: Piston for hydraulic systems
A customer contacted us, as he wanted us to design and produce of at piston for a hydraulic system in a truck engine.
The idea behind the mechanisem, was that piston should move inside a cylinder, that was interconnected with two tanks. The pistons movement through the cylinder, should act as the open and close mechanism for respectively tank 1 and tank 2.
How we manufacture the piston
The piston consists of two steel cups and a tube that connect the cups. As the piston is a part of an environment with temperature fluctuations, it is made from stainless steel to prevent corrosion.
Instead of manufacturing the piston by using a turning operation, the piston is made as a sheet metal solution. Using a sheet metal solution, significantly reduces the material waste, compared to a turned solution, as no chips are being produced.
The two cups on the piston are formed through a deep drawing-operation, with subsequent assembly. The steel cups are assembled in a simple but clever solution, with a join that locks together the two cups to the steel tube that connects them. In that way, we avoid adding tensions to the material, deriving from a welding operation.
To ensure a tight fit between the piston and the cylinder, and to prevent wear, it is of great importance that the two cups on the piston has exactly the same diameter, and is assembled in a way that comply with tight position tolerances. Therefore, the assembled construction of the two cups and the tube, is collectively turned in a CNC machine to ensure concentricity.