How can planetary gearboxes ensure high torque output capability through material selection and heat treatment?

(1) Material selection: Laying the foundation for high strength and reliability
Material is a key factor affecting the load-bearing capacity of gears. We usually select the following materials for gears and structural parts:
Gear part:
Alloy structural steel (such as 20CrMnTi, 18CrNiMo7-6):
These materials have hardenability and can form high hardness on the gear surface while retaining good toughness in the core, suitable for high-load conditions.
Medium carbon steel (such as 42CrMo):
This material is often used for gears that require higher toughness and impact resistance, suitable for more demanding working environments.

Bearings and shafts:
High-strength alloy steel (such as GCr15 or 40Cr) is usually used to ensure its stability and life under high load and continuous rotation.

Casing material:
Use high-strength cast iron (such as HT250) or low-alloy steel plate welding to improve rigidity and fatigue resistance and avoid deformation of the casing due to high torque output.

(2) Heat treatment: The core process for strengthening the load-bearing capacity of gears
The heat treatment process determines the performance of the material, which is especially important for high-load running parts such as gears.
Carburizing and quenching: improving surface hardness and wear resistance
The surface of the gear is treated with carburizing and quenching to form a hardened layer with a hardness of up to HRC58-62, which has extremely strong wear resistance and fatigue resistance.
The depth of the hardened layer is generally between 0.8-2mm, which is adjusted according to the gear modulus and load requirements to ensure that it can resist surface wear and withstand impact under high load.

Nitriding treatment: improving fatigue resistance
For some gears that require corrosion resistance or higher fatigue life, nitriding treatment technology is used, and the hardness can reach HV700-1000, while reducing heat treatment deformation and ensuring gear accuracy.

Tempering treatment: improving toughness and stability
The core of the gear is tempered to reduce the internal stress of the material and improve toughness, thereby preventing the gear from cracking due to excessive brittleness under high torque.

(3) Technical optimization: further improving material performance

In addition to basic material selection and heat treatment processes, we also further optimize through the following methods:
Material composition control
Add trace alloying elements (such as molybdenum and vanadium) to improve the gear's anti-tempering stability and wear resistance, while reducing the risk of quenching distortion.

Surface treatment process
After the heat treatment is completed, the surface is shot peened to enhance the fatigue resistance by introducing surface compressive stress, which is particularly suitable for scenarios that require long-term high-load operation.

Box rigidity optimization
Perform finite element analysis (FEA) on the box and design a reasonable reinforcement rib layout when subjected to high torque to avoid box deformation affecting the gear meshing accuracy.

(4) Matching materials and processes: achieving a balance between performance and cost
When manufacturing high-performance planetary gearboxes, it is necessary to strike a balance between performance and cost.
For heavy equipment that requires extremely high loads, we will give priority to high-performance alloy steel and multi-stage heat treatment processes.
For ordinary industrial equipment, we use more cost-effective medium-carbon steel materials and standardized processes to ensure that performance requirements are met while controlling costs.

(5) Practical application case: Excellent performance of high-torque gearbox
Wind power industry: The wind power gearbox adopts 18CrNiMo7-6 gears that have been carburized and quenched, which has high hardness and strong wear resistance, and can stably transmit hundreds of tons of torque.
Mining equipment: The planetary gearbox of the excavator uses 42CrMo forged gears with deep carburization treatment, and it can withstand impact loads and high torque conditions for a long time and still perform stably.

As a Chinese high-tech listed company, our company focuses on the research and development, production, sales and service of brushless DC motors and servo drives, micro AC and DC motors, high-precision cycloid gearboxes, harmonic gearboxes and planetary gearboxes. Our products are widely used in industrial robots, intelligent logistics, new energy, machine tools and other fields, and also serve special machinery and equipment in the food, packaging, textile, electronics, medical and other industries. With differentiated design and high cost-effectiveness, our planetary gearbox products excel in high torque output requirements, have extremely high reliability and application value, can meet the diverse needs of customers and help their equipment achieve high performance and high efficiency operation goals.