Isotropic superfinishing of large gears

In view of the ever growing durability demands on gears used in large gearboxes, Osro and REM have jointly developed machines and Isotropic Superfinishing (ISF®) Processes, specifically tailored to improve the surface finish of large gears.

The machines used in the ISF® Process are designed to cope with the extreme weight of these large gears. Various machines are available for super finishing gears weighing up to 1200 kgs. Pinions up to 1000 kgs and Inverse gears, (sometimes referred as the hollow wheels), up to 2000 kgs. Machines and processes for larger gears, (up to 5000 kg), are currently being developed.

The ISF Process uses an effective and proven method of surface refinement to increase the wear resistance of the gears. The surface improvement of the gear flanks results in a reduction in grey staining and micro pitting. The improved surface finish generated by the ISF process produces an improved load carrying capacity, lubrication regime,(EHL), and consequently greatly reduced wear.

Bearbeitung einer Ritzelwelle
Superfinishing von 2 MW Getriebeteilen
Superfinishing - Anlage für Stirnräder

The benefits are:

  • Reduction of surface roughness

  • Improved load carrying capacity

  • Improvement of grey staining resistance

  • Elimination of running in wear

  • Improvement of scuffing load capacity

  • Improvement of micro-pitting resistance

  • Reduction in lubricant filtration maintenance

  • Lower operating costs

  • Lower operating temperatures

The advantages of the Process can be applied to all gears whatever the application. However, specifically planetary gearboxes having Low Speed - High Load operating regimes gain tremendous benefit from the ISF® process, particularly when not only the planets and the sun wheel, but also the inverse gear is Superfinished.

The ISF® Process is also suitable for gearboxes which suffer from extreme wear and have to be rebuilt. Experience has shown that Superfinishing of the replacement new gears, prior to assembly, can produce an up to three-fold increase in life expectancy. (Please note that it is not recommended to super finish damaged or micro-pitted gears)