18CrNiMo7-6 High Hardness Planetary Gears For Machine Transmissions

18CrNiMo7-6 High Hardness Planetary Gears For Machine Transmissions

Planetary gears are high-precision coaxial transmission gear sets, mainly composed of sun gear, planet gears, inner ring gear and planet carrier. Made of high-strength alloy steel through precision machining, they feature coaxial drive, speed reduction, torque increase, uniform load distribution and compact structure. Widely used in automobile transmissions, new energy electric axles, industrial reducers, engineering machinery and automatic equipment, they realize large speed ratio, high torque and high-efficiency stable transmission in limited space, serving as core precision components of modern power transmission systems.

Product Features

• Integrated coaxial transmission with concentric input and output shafts, occupying very little space.
• Multiple planet gears share load jointly with uniform stress and greatly improved load capacity.
• Wide speed ratio range; single-stage and multi-stage combination achieves diversified reduction ratios.
• High transmission efficiency, stable operation, low vibration and low noise.
• Compact and lightweight structure, smaller size and lighter weight than ordinary fixed-axis gears.
• Hardened tooth surface by carburizing and quenching with high hardness, wear resistance, impact resistance and fatigue resistance.
• Adaptable to forward and reverse rotation, high-speed heavy load and long-time continuous operation.

 Technical Parameter Table

 Main Applications

• NEV electric drive reducers and hybrid DHT transmissions
• Internal planetary gear sets for automobile AT and DCT transmissions
• Industrial coaxial planetary reducers and servo precision reducers
• Transmission components for construction machinery and vehicle transfer cases
• Precision reduction parts for robot joints and mechanical arms
• Transmission mechanisms for wind power and photovoltaic equipment
• Auxiliary power transmission systems for rail transit and ships
• Drive parts for automatic equipment and AGV intelligent logistics vehicles

Product Advantages

• Multi-gear load sharing design, with much higher load capacity than ordinary gears in the same volume.
• Coaxial transmission with concentric shafts, occupying minimal installation space with compact layout.
• Wide speed ratio range, flexible single and multi-stage combination for various reduction demands.
• High transmission efficiency over 97% per single stage with low energy consumption.
• Stable operation, small backlash, low vibration and low noise, suitable for high-speed conditions.
• High structural rigidity, impact resistance, fatigue resistance and long service life.
• Outstanding lightweight advantage to greatly reduce overall equipment weight.
• Flexible transmission modes with combinable functions of speed changing, power splitting and clutching.

Production Process

• Raw Material Inspection → 2. Precision Forging of Blanks
• Pre-heat Treatment (Normalizing & Stress Relief) → 4. CNC Turning of Gear Blanks
• CNC Gear Hobbing → 6. Profile & Lead Modification
• Carburizing & Quenching Strengthening → 8. Low Temperature Tempering for Stress Relief
• Precision Grinding of Bore, End Face and Outer Circle
• CNC Gear Grinding for High Precision Finishing
• Deburring, Cleaning and Non-destructive Flaw Detection
• Comprehensive Inspection of Dimension, Backlash and Hardness
• Planetary Set Matching, Anti-rust Treatment, Cleaning and Packaging

 Cautions

• Planetary gears must be used in complete matched sets; mixed installation and random replacement are strictly prohibited.
• Over-speed and over-torque overload operation are forbidden to avoid gear fracture and planet carrier deformation.
• Dry running without lubricant is prohibited to prevent tooth scuffing, pitting and abnormal wear.
• Do not strike tooth surfaces during installation to avoid profile deformation and precision damage.
• Ensure uniform load on planet gears; uneven clearance will cause partial load and early failure.
• Keep housing sealed to prevent dust and impurities from causing abrasive wear.
• Operating temperature shall not exceed rated range to avoid high-temperature lubricant failure.
• Stop machine immediately for maintenance when abnormal noise, severe vibration or overheating occurs.
• The whole set shall be replaced integrally when gears suffer severe wear, chipping or pitting.
• Store in dry and ventilated environment with anti-rust treatment to avoid corrosion affecting precision.

Why Choose us?

• 7-axis CNC Grinding: We adopt high-precision 7-axis CNC grinding machines, holding tolerances as tight as ±5μm, ensuring gears run quietly, smoothly and with outstanding durability.
• Strong technical expertise: Our core R&D team includes doctoral and master’s professionals specializing in spiral bevel gear technology, providing strong technical support for complex projects.
• Rigorous testing & high precision: All gears undergo 100% inspection with Gleason metrology systems. We can achieve DIN 6 grade accuracy with strict control over tooth profile and direction errors, keeping our quality at the industry-leading level.
• High transmission efficiency: Our gear designs support a single-stage reduction ratio of up to 300:1, with actual transmission efficiency reaching over 95%, greatly improving energy utilization.
• Excellent durability & cost efficiency: Our gears deliver 40% lower lifecycle cost and a failure rate below 0.5%, ensuring stable long-term operation and reduced maintenance costs.
• Fast response & short lead time: Supported by our digitalized production process, we are able to shorten the delivery cycle to only 20 working days, helping you accelerate project development and launch.
• Professional custom design capability: We provide fully customized gear solutions for applications requiring high-reduction, high-speed, heavy-load, low-noise, and special small-tooth profiles, based on your actual working conditions.