Precision Servo Planetary Gear Sets
Low-backlash (< 3 arcmin) helical and spur epicyclic gear kits with CNC profile-ground teeth and matched planet sorting for robotics and automation servo gearheads.
Planetary Gear Sets Manufacturer
Planetary Gear Sets
High-torque, compact planetary gear sets—including precision ground sun gears, matched planet pinions, CNC-bored planet carriers, and internal ring gears—engineered for servo reducers and mobile drivetrains.
Source Factory
China Direct (2,800m² Plant)
Precision Grade
DIN 4-7 / AGMA 11-13
Engineering DFM
< 24 Hours Turnaround
Quality System
ISO 9001:2015
Featured Product Model & RFQ Specifications
Custom Planetary Gear Sets
China direct OEM factory for custom planetary gear sets—manufacturing precision ground sun gears, matched planet pinions, CNC-bored planet carriers, and internal ring gears strictly to your 2D/3D drawings or samples.
Kit components
Central sun gear/shaft, 3 to 6 matched planet pinions, planetary carrier, and internal ring gear (annulus)
Manufacturing basis
Customer 2D/3D CAD prints (STEP/IGES/PDF), gear data sheets, or physical gearbox samples
Module & Pitch range
Metric Module M0.5 to M12 (Diametral Pitch DP 48 to DP 2); Spur or Helical (helix angle up to 30°)
Tooth accuracy grades
DIN 5 to DIN 7 (ISO 1328 Grade 5–7 / AGMA 11–13) via CNC tooth flank profile grinding
Manufacturing capability
Technical Overview & Engineering Capability for Planetary Gear Sets Manufacturer.
As an ISO 9001-certified planetary gear sets manufacturer and direct OEM factory in Wenling, Zhejiang (2,800+ m² plant, supplying industry leaders such as Newstart Planetary Reducers and Weichai Power), ZhongYi produces custom epicyclic gearing strictly from buyer CAD drawings or samples. Planetary gear systems split transmitted torque across 3 to 6 planet pinions simultaneously, delivering exceptional power density, coaxial shaft alignment, high torsional stiffness, and low backlash (< 3 to 10 arcmin). Because epicyclic gear performance relies on synchronized multi-mesh tolerances, our complete in-house scope covers central sun gears (integral with input shafts or splined bores), matched planet pinions with precision-honed needle roller bearing bores, 5-axis CNC machined planet carriers, and low-distortion nitrided or carburized internal ring gears.
Tooth AccuracyDIN 4-7 / AGMA 11-13
Tooth FinishingCNC Ground (Ra ≤0.4µm)
Heat TreatmentCarburized 58-62 HRC
Product types & variants
Planetary Gear Sets types and manufacturing paths.
The final product form is confirmed from the buyer drawing, mating component, assembly layout, operating conditions, and inspection requirements.
Heavy-Duty Construction & Final Drive Sets
Multi-stage high-torque 18CrNiMo7-6 / 20CrMnTi carburized planet gears and forged 42CrMo carriers engineered for excavator track drives, wheel loaders, and hydraulic winches.
Sun Gears & Integral Input Sun Shafts
High-speed central pinions and integral motor-input sun shafts featuring DIN 5480 involute splines, precision bearing journals (TIR ≤ 0.005 mm), and lead crowning.
Internal Ring Gears (Annulus) &Planet Carriers
CNC gear-shaped or broached ring gears with plasma nitriding for zero-distortion roundness, paired with CMM-verified 5-axis machined single- or double-wall planet carriers.
Selection & Metallurgy guidance
How to specify the correct planetary gear sets configuration.
When specifying a planetary gear set, first verify the three kinematic assembly conditions: (1) Concentricity: Z_ring = Z_sun + 2·Z_planet (or balanced via profile shift x for non-standard center distances); (2) Symmetric Planet Spacing: (Z_sun + Z_ring) / N_planets must equal an integer so all planets space equally at 360°/N; and (3) Adjacency: adjacent planet tip diameters must not collide. Because carrier torsional windup and pin position tolerances cause uneven load sharing (Kγ) across multiple planets, specify whether micro-geometry lead crowning (Cβ), floating sun gears, or grouped span-measurement matching are required. Include 2D/3D drawings, module/DP, helix and pressure angles, backlash target, needle bearing bore specs, and duty cycle in your RFQ.
Material & Heat Treatment Options
- Case-carburizing alloy steels (18CrNiMo7-6 / DIN 1.6587, 20CrMnTi, AISI 8620, 20CrMo) for high Hertzian contact fatigue resistance on sun and planet gears
- Nitriding alloy steels (42CrMo / AISI 4140, 38CrMoAlA) for minimal thermal distortion on thin-walled internal ring gears (annulus)
- Quenched & tempered high-tensile forged steels (42CrMo, 40Cr at 28–34 HRC) and ductile iron (QT600-3 / GGG60) for rigid single- and double-wall planet carriers
- Specialty copper-bronze alloys and engineering polymers (PEEK, POM) for low-noise instrument or lubrication-restricted planetary drives
Engineering Selection Factors
- Three kinematic assembly equations: Concentricity (Z_ring = Z_sun + 2·Z_planet), Symmetric Spacing ((Z_sun + Z_ring) / N_planets = integer), and Adjacency clearance
- Stage reduction ratio, input RPM, rated continuous output torque, and peak emergency shock torque
- Target torsional backlash class: Ultra-Precision (< 3 arcmin), Precision (< 5 arcmin), or Standard (< 8–10 arcmin)
- Load-sharing architecture: floating sun gear, flexible planet pins, and grouped planet span measurement sorting (ΔMk ≤ 0.004 mm)
- Planet pinion inner bore design (direct needle roller raceway vs. pressed bronze bushing) and carrier pin hole true position (≤ 0.012 mm)
Quality Control & Inspection Matrix
Engineering Evidence & 100% Inspection for Planetary Gear Sets.
Overseas procurement teams require verifiable technical data, not unsupported claims. Every production batch at ZhongYi is inspected against approved CAD blueprints and international standards (DIN, AGMA, ISO).
Component-Specific Quality Focus:
Planetary gear sets are manufactured and inspected as synchronized kinematic kits under our 9-step ISO 9001:2015 metrology protocol. Using Zeiss 3D coordinate measuring machines (CMM) and Klingelnberg CNC gear measuring centers, we verify planet carrier pin-hole true position (≤ 0.012 mm) and parallelism, sun and planet tooth profile/lead crowning charts (Fα, Fβ, Fp to DIN 5–7), internal ring gear pitch roundness, needle bearing bore cylindricity, and effective carburized case depth. Planet pinions are serialized and grouped in matched sets by over-pins diameter (span measurement ΔMk ≤ 0.004 mm), with full EN 10204 Type 3.1 Material Test Reports (MTR) supplied before shipment.
Coordinate Metrology
Zeiss / Hexagon 3D CMM
Validates 3D spatial GD&T, bore concentricity, center distance, and geometric tolerances down to ±0.002 mm.
Tooth Geometry Analysis
Klingelnberg CNC Gear Analyzer
Inspects involute tooth profile error (fα), lead crowning (fβ), pitch cumulative error (Fp), and radial runout (Fr).
Hardness & Case Depth
Digital Micro-Vickers & Rockwell Testers
Verifies surface hardness (58–62 HRC), core toughness, and effective carburized / nitrided case depth gradient.
Chemical Metallurgy
Direct-Reading Optical Spectrometer
100% chemical composition verification of alloy steel forgings (20CrMnTi, 42CrMo, 18CrNiMo7-6, Stainless, POM).
Inspection Deliverables with Every Shipment
Complete Batch Traceability & Certified Test Reports
- EN 10204 Type 3.1 Mill Test Certificate (Chemical & Mechanical Properties)
- Zeiss 3D CMM Full Dimensional Inspection Sheet
- Klingelnberg Tooth Profile & Lead Crowning Graph Report
- Effective Carburized Case Depth & Hardness Curve Data
- 100% Pre-Shipment Visual, Thread & Anti-Rust Quality Verification
Our Factory Quality Commitment:
We maintain strict incoming material spectroscopy, in-process CNC tooth coordinate monitoring, and 100% final pre-shipment dimensional inspection. All custom gear batches are backed by our full manufacturing warranty.
ISO 9001:2015 Certified
DIN 4-7 / AGMA 11-13 Standards
Application fit
Planetary Gear Sets operating environments.
Match the gear type with real machinery conditions, operating environment, load, speed, and replacement requirements.
- Precision low-backlash servo planetary gearboxes for industrial robotics, AGV wheel drives, and CNC machine tool axes
- Heavy-duty hydrostatic wheel drives, track final drives, and winch reducers for excavators and construction machinery
- Slew drive gearboxes, rotary drilling heads, and mobile crane swing transmissions
- Wind turbine pitch and yaw drive reducers, solar tracking slewing drives, and agricultural tractor final drives
Application Markets
View All 5 Industry Hubs →Where Planetary Gear Sets Are Engineered & Deployed
Discover how this gear category meets extreme torque, low backlash, quiet operation, and weather-resistance demands in primary industry sectors:
🏗️Heavy-Duty & High-Impact Transmission
Construction & Mining Machinery
High-torque, impact-resistant gears, girth rings, and planetary drive sets engineered for excavators, cranes, drilling rigs, and heavy mining crushers.
🌬️20-Year Outdoor Longevity & High Wind Torque
Renewable Energy
Heavy-torque yaw/pitch gears, slewing ring drives, and precision worm drives engineered for 20-year service life in wind turbines and solar tracking fields.
Technical FAQ
Common technical and purchasing questions for Planetary Gear Sets.
These answers support early engineering and procurement review. Final dimensions, materials, tolerances, and process requirements are confirmed against the approved drawing file.
Why source planetary gear sets from a China manufacturer like ZhongYi?▼
ZhongYi manufactures all four epicyclic components (sun gear, matched planet pinions, planet carrier, and internal ring gear) under one roof in our 2,800+ m² Zhejiang factory. Proven by long-term OEM supply to leading reducer brands like Newstart Planetary Reducers and Weichai Power, we eliminate multi-vendor tolerance stacking while providing DIN 5–7 CNC gear grinding and direct factory export pricing.
What are the three kinematic assembly conditions for planetary gears?▼
First, Concentricity requires Z_ring = Z_sun + 2·Z_planet (for standard non-shifted gears). Second, Symmetric Spacing requires (Z_sun + Z_ring) / N_planets = integer so N planets can be spaced at equal angles. Third, Adjacency requires (Z_sun + Z_planet) · sin(180° / N_planets) > Z_planet + 2 to prevent adjacent planet teeth from colliding.
How does ZhongYi ensure equal load sharing (Kγ) across all planet gears?▼
We combine three manufacturing controls: (1) 5-axis CNC boring of planet carrier pin holes held within ≤ 0.012 mm true position; (2) CNC tooth flank grinding with parabolic lead crowning (3–15 µm) to compensate for carrier torsional deflection; and (3) sorting planet pinions into matched sets with span measurement variance ≤ 0.004 mm.
Should the internal ring gear be carburized or nitrided?▼
For thin-walled ring gears or integrated housing rings, plasma or gas nitriding using 42CrMo or 38CrMoAlA steel is ideal because it achieves 650–750 HV surface hardness with near-zero thermal distortion—maintaining DIN 6–7 accuracy without expensive internal grinding. For extreme shock-load mining or wind drives requiring deep case hardening (> 1.5 mm), we use 20CrMnTi or 18CrNiMo7-6 carburizing followed by CNC internal gear grinding.
How do you machine planet gear bores for needle roller bearings?▼
Because the planet pinion bore frequently acts directly as the outer raceway for needle rollers, we case-carburize the bore to 58–62 HRC and finish it via precision internal cylindrical grinding or honing, holding size tolerance to ISO H6/G6, cylindricity ≤ 0.005 mm, and surface roughness Ra ≤ 0.2–0.4 µm.
Can ZhongYi reverse-engineer replacement planetary gear sets from worn samples?▼
Yes. By measuring your worn sun, planet, carrier, and ring gear samples on our Zeiss CMM and gear analyzer, we back-calculate the exact module, helix angle, and profile shift coefficients (x), delivering a complete matched replacement set that restores original backlash and acoustic performance.
24-Hour Engineering Quote & DFM Review
Upload Your Drawings for Planetary Gear Sets Manufacturing
Send your 2D blueprints or 3D CAD models. Our senior gear engineering team will review tooth geometry, module/pitch, materials, heat treatment feasibility, and provide transparent factory pricing within 24 hours.
Supported CAD Blueprint & Drawing Formats:
STEP (.step / .stp)AutoCAD (.dwg / .dxf)IGES (.igs)SolidWorks / 3D CADPDF Technical BlueprintsWorn Physical Samples
Mutual NDA Protection
We sign strict Non-Disclosure Agreements to safeguard proprietary designs.
< 24h DFM Feedback
Rapid manufacturability review, tolerance checks, and unit quotation.
Direct Factory Engineering
Direct technical communication with senior master gear artisans.
Engineering Knowledge Cluster
Technical Design, Metallurgy & Sourcing Guides for Planetary Gear Sets
Explore in-depth kinematic calculations, load-sharing tooth crowning methods, heat-treatment comparisons, and OEM specification checklists written by our gear engineers.
Kinematics & Design9 min read
Planetary Gear Ratio & Assembly Condition Calculation Guide (With Examples)
Before releasing a planetary gear set drawing for CNC machining, engineers must verify three mandatory geometric constraints—concentricity, symmetric planet spacing, and adjacency clearance—alongside the Willis kinematic speed ratio.
Engineering GuideRead Article →
Kinematics & Design10 min read
Planetary Gear Load Sharing (Kγ) and Tooth Lead Crowning Explained
Adding more planet pinions does not automatically multiply torque capacity in a linear 1:1 ratio. Without micro-geometry tooth lead crowning and tight carrier pin position control, a single overloaded planet can carry over 50% of the total load.
Engineering GuideRead Article →
Reducer Comparison8 min read
Planetary Gear vs. Harmonic Drive vs. Cycloidal Drive: Engineering Selection Guide
Choosing the wrong speed reducer architecture for a robotic joint, AGV drivetrain, or CNC axis either starves the system of mechanical efficiency or drives BOM costs up by 300%. Here is a quantitative engineering comparison.
Engineering GuideRead Article →
Reducer Comparison8 min read
Helical vs. Spur Planetary Gears: Noise, Axial Thrust, and Torque Capacity
Upgrading a planetary stage from straight spur teeth to angled helical teeth can drop gearbox noise by 4 to 8 dB(A) and boost torque ratings by 20%–30%—but it introduces overturning moments on the planet needle bearings that must be engineered properly.
Engineering GuideRead Article →
Manufacturing & Metallurgy9 min read
Materials & Heat Treatment for Planetary Gears: Carburizing vs. Nitriding
Applying the same heat-treatment specification to all four components of a planetary gear set is a costly mistake. Here is why sun and planet pinions demand deep case carburizing while internal ring gears thrive on plasma nitriding.
Engineering GuideRead Article →
Troubleshooting & MRO9 min read
Planetary Gear Failure Modes: Diagnosing Pitting, Tooth Breakage, and Backlash
In 70% of catastrophic planetary gearbox breakdowns, the broken gear teeth found in the sump are the final symptom—not the root cause. Use this metallurgical and kinematic diagnostic guide to pinpoint failure origins.
Engineering GuideRead Article →
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