Case: Gear wheel for mobile hydraulics
This case concerns a gear used in a mobile hydraulic system. It is essential for hydraulic systems that the material is strong and durable. For this reason, the gear is made of black steel, with a special alloy that makes the material stronger.
How we manufacture the gear wheel
The gear is manufactures through a cold forging process.
Forming the geometric shape of the gear happens in only one operation, on a press that provides 1800 beats per hour. The production process is thus well suited to to handle up to very large production series.
Cold forging is a process in which the metal is formed without heating up the material. Instead, a cut off steel rod is pressed out cold to the finished shape, in a press that can provide a pressure of up to 1000 ton. Cold forging provides stronger items than e.g. casted items, as casted items always contain small gas pockets due to the heating process. This makes casted items more porous and brittle, than cold forged items. As cold forged items preserve more material strength after machining this process is ideal for hydraulic systems.
Another advantage of using a cold forging process for hydraulic systems, is that the process allows designs, with very narrow tolerances, which is often required when manufacturing transmission units such as this gear unit. The manufacture of this gear meets the requirements of a tolerance class ISO 1328 and the item also meets a class 8 toothing specification inside the gear.