Gear Hobbing

What is Gear Hobbing?

Gear hobbing is a quick and accurate manufacturing process for producing gears or cogwheels, such as those found in horizontal and vertical pumps used in the oil and gas industry. Hobbing is the most widely used gear cutting method for creating spur and helical gears.

Gear hobbing machines utilize a special cylindrical hob that features helical cutting teeth. These teeth have grooves that run the length of the hob and aid in cutting and chip removal. The cross-sectional shape of the hob teeth is almost the same as the teeth of a rack gear that would be used with the finished product. There are slight changes to the shape for generating purposes, such as extending the hob’s tooth length to create a clearance in the gear’s roots. The teeth generate a tooth profile on gear blanks as they are fed through the machine. Both the hob and the gear blank rotate as the hob is fed axially across the workpiece. This process is repeated until the required depth is obtained.

For even faster production, multiple gear blanks can be stacked on the spindle together, allowing the hob to cut all material at once. This manufacturing technique is one of the fundamental processes of gear manufacturing and is both accurate and affordable.