A Helical-Planetary gearbox is a type of combination gearbox in which the first stage of reduction is achieved using a helical pinion-gear pair and the output of this stage is given as input to the Planetary Gear Box. The helical gears provide higher power handling capacity and smoother operation compared to straight-cut gears, while the planetary gear arrangement allows for compact design with high power density and the ability to handle higher torque loads.
These are typically beneficial when the input power is high and the output torque is also high. The first helical stage gives the advantage of enabling high power input with better thermal efficiency and the planetary stage gives advantage of High Power Density (compact size compared to any other type of gear box with same torque rating).
Helical Planetary gearboxes are commonly used for High Torque & High Input Power applications typically for Sugar Industry etc. These are also known as Helical Planetary Gear Drives.
Ratio - 5 Onwards
Input Power - Upto 500 kW
Maximum Torque Rating - 5,00,000 N.m