Internal Gears & Splines

Internal gears and splines have teeth on the inside diameter of a hollow cylinder. The teeth of internal gears are of involute form; however, the profile is concave rather than convex as is the case with the involute profile of external gear teeth. Internal gears must mate with one or more external gears and their primary application is as a component of an epicyclic (planetary) gear arrangement. Internal gear teeth may be of the spur or helical form and the mating gear must be of the same type and have the axis of rotation situated parallel to that of the internal gear.

Internal splines are generated using the same processes as internal gears and usually mate with shafts having external splines to transmit power and rotation in a single axis. The teeth of internal splines may be of various forms including involute, parallel and serrated.

Internal Gear & Spline Experience

Geartronics produces thousands of internal gears annually primarily for use in planetary gear sets many of which are assembled right at our facility in North Billerica, Massachusetts. A large percentage of the internal gears that we manufacture are also routed through our CNC milling and grinding centers for the addition of various machined features such as slots, thru holes, counterbores, threaded holes, engraving and tightly-toleranced diameters.

We have manufactured internal gears and splines for customers from a number of industries, including:

  • Aerospace
  • Appliance
  • Automotive
  • Consumer Product
  • Defense
  • Food Processing
  • Hand & Power Tools
  • Industrial Equipment
  • Machine Controls
  • Medical Device & Equipment
  • Motion Control
  • Oil & Gas

Internal Gear & Spline Materials

Geartronics has the capability of producing internal gears and splines from a wide range of materials, including:

Alloy Steel
Castings & Forgings
Carbon Steel
Ductile Iron
Pre-Heat Treated Steel
Stainless Steels
Tool Steel

contact us

Geartronics Incorporated
100 Chelmsford Road
North Billerica, MA 01862

Call Us: 978.663.6566

Fax: 978.667.3130