Here at Newmont we have years of experience in manufacturing internal gears and internal gear couplings.

Internal gears are a type of spur gear whereby the teeth are cut on the internal surface of the cylinder - usually used in applications involving planetary systems involving gear drives and gear couplings.

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External Gears have teeth cut on the outside surface of the mating wheel.  Depending on the type, pattern and arrangement of the gears and shafts in the system, you can create devices with different transmission ratios and velocity ratios using an internal gear and a combination of external gears.