Internal Ring Gear

CNC Gear Shaping of a Forged Steel Alloy Ring Gear for the Large Mining Vehicle Industry

Internal Ring Gear Example









Internal Ring Gear Capabilities
Product Description Used on large mining trucks

Capabilities Applied/Processes

CAM Programming
In-House Fixture Development - Tooling
CNC Vertical Turning
CNC Gear Shaping


Equipment Used to Manufacture Part

1 Meter Vertical Turning Center
1.2 Meter Gear Shaper

Overall Part Dimensions

1000mm (39.4 in) Outside Diameter
874 mm (34.4 in) Inside Diameter
72 Teeth
12.1 Module (2.0992 D.P.)
270 mm (10.6 in) Face Width

Tightest Tolerances

Gear Measurement
• ± 0.064mm (.0025” inch) Measurement Between balls
• Gear Tooth Modification Needing Identified at 23.28° of Roll, via CMM Gear    Inspection
• Gear Quality: AGMA A8 / Q9

Material Used

Steel Alloy Forging

Material Finish

Surface Finish Gear Tooth Profile .047 (μin.)

In process testing/inspection performed

On-machine inspection with gages or Faro Arm.

CMM Inspection

Industry for Use



100 Pieces per Month in Production

Delivery/Turnaround Time

20 Day Lead Time

Standards Met

Customer Specifications
2D CAD Drawing
Customer Required Control Plan (SPC)
Geometric Dimensioning Tolerance

Project Challenges

This part highlights RMC's capability for precision course pitch internal gear shaping.