Planetary Ring Gear
Brand: Hansheng
Accuracy grade: ISO/DIN/GB level 5
Gear module: 0.1–5.0
Tip diameter: 3 mm–300 mm
Introduction
Product Overview
Our planetary ring gear is the outermost stationary component of a planetary gear system. Precision machining ensures tight tooth profile tolerances. The gear meshes seamlessly with planet gears to deliver high torque density. This compact design optimizes power transmission for automatic transmissions, robotics, and industrial reducers. Every planetary ring gear we manufacture undergoes full dimensional inspection and surface hardness verification before shipment.
Need a custom planetary ring gear?
We will reply to your message within 24 hours.
Key Specifications
Standard parameter range for our planetary ring gear series. Custom configurations available upon request.
| Parameter | Standard Range |
| Module | 0.1 – 5.0 |
| Number of Teeth | 24 – 400 |
| Pressure Angle | 20° |
| Helix Angle | 0° – 45° |
| Tip Diameter | 3 – 300mm |
| Tooth Profile Accuracy | ISO Grade 5 – 9 |
| Material | 20CrMnTi / 42CrMo4 / 8620 |
| Surface Hardness | 58 – 62HRC |
We have more products related to ring gear available here.
Why Choose Our Planetary Ring Gear
- High torque density
Multiple planet gears share load simultaneously, enabling compact designs with up to 10:1 ratio in a single stage.
- Coaxial output
The input and output shafts share a common axis to optimize space-constrained gearboxes and hub motor applications.
- Custom tooth profile
Full-depth, stub, and modified involute profiles available. Match existing sun gear geometry precisely.
- In-house strength verification
Root bending and contact stress calculated using standard gear engineering methods for each production batch. Full inspection reports available.
Custom planetary ring gear service
From single prototype to high-volume production, we engineer and manufacture custom planetary ring gears to your exact drawing or specification, with full dimensional reports included on every order.
Submit requirements
Provide your module, tooth count, and material via our web form. You can also email DXF or DWG drawings directly to our team.
Engineering review
Our engineers verify meshing geometry and perform gear strength calculations and meshing geometry verification. We confirm manufacturability within 24 hours.
Quotation & DFM
You receive a formal quotation and a free DFM report. This report suggests specific parameter optimizations for your design.
Production & QC
We execute precision hobbing, grinding, and heat treatment. Every order ships with a complete CMM dimensional and hardness report.
FAQ
What is the function of a planetary ring gear in a gearbox?
The planetary ring gear acts as the outer fixed housing that planet gears orbit inside. It transfers torque between the planet gears and the gearbox casing, enabling compact, high-ratio power transmission. Without it, the planetary gear system cannot achieve coaxial speed reduction or torque multiplication efficiently.
What materials are used for planetary ring gears?
Common materials include carburizing steels such as 20CrMnTi and 8620 for high-load applications, and through-hardened alloy steels like 42CrMo4 for moderate loads. Material selection depends on torque, speed, and operating temperature. Our engineering team recommends material grades based on your gearbox design parameters.
How is the ring gear tooth count calculated in a planetary set?
The fundamental equation is: Z_ring = Z_sun + 2 × Z_planet. This ensures all gears assemble correctly and planet gears mesh simultaneously. For example, a sun gear with 20 teeth and planet gears with 40 teeth requires a ring gear with exactly 100 teeth to maintain proper meshing geometry.
Can you manufacture a non-standard or custom planetary ring gear?
Yes. We manufacture custom planetary ring gears from Module 1 to Module 20, outer diameters up to 1200mm, and in various tooth profiles including helical and modified involute. Provide your tooth count, module, face width, and material requirement — our team will respond within 24 hours with a detailed quotation.
What is the difference between a ring gear and an annular gear?
They are the same component referred to by different names. “Ring gear” is common in automotive and industrial engineering, while “annular gear” is the formal ISO/AGMA terminology. Both describe an internal gear with teeth on its inner circumference that meshes with planet gears within a planetary gear system.
