How to accurately select the key parameters of planetary gearboxes according to project requirements?

1. Load capacity
The load capacity of the planetary gearbox determines the reliability and life of the equipment under actual working conditions. Therefore, evaluating the load characteristics of the equipment is the first priority.
Maximum output torque: Determine whether the rated torque of the gearbox meets the project requirements. It is recommended that the rated torque of the selected gearbox should be at least 20%-30% greater than the working torque to cope with sudden overloads and long-term operation losses. For heavy-load scenarios (such as mining equipment and lifting machinery), special attention should be paid to the impact load bearing capacity and fatigue resistance of the gearbox.
Start and stop frequency: Equipment with high-frequency start and stop (such as packaging machinery and electronic equipment assembly lines) has high requirements for the dynamic response ability of the gearbox, and it is necessary to select models with good lubrication performance and low return clearance. If the equipment has a high load impact at the moment of starting (such as a press), it is necessary to calculate the peak torque at startup and ensure that the gearbox has sufficient bearing capacity.
Axial and radial loads: Under some working conditions, the input shaft or output shaft of the gearbox will be subject to axial or radial external loads (such as the axial pressure caused by the blades in a wind turbine). In this case, it is necessary to check whether the bearing design of the gearbox can meet the additional load requirements.

2. Transmission ratio
The transmission ratio of a planetary gearbox is one of its core technical indicators, which directly affects the output speed and accuracy.
Working speed requirements: When selecting the transmission ratio, it should be calculated based on the speed of the drive motor and the output speed of the target device. For example, if the motor speed is 3000 rpm and the target device requires 100 rpm output, the transmission ratio should be 3000 ÷ 100 = 30. It should be noted that a gearbox with a high transmission ratio may sacrifice some efficiency, so it is recommended to choose a lower transmission ratio while meeting the requirements.
Torque amplification effect: An increase in the transmission ratio is usually accompanied by an increase in the output torque. For example, a gearbox with a transmission ratio of 10 will amplify the input torque by 10 times to ensure sufficient output power. However, it is necessary to pay attention to the decrease in transmission efficiency.
Multi-stage design requirements: For ultra-high transmission ratio requirements (such as more than 1:100), a multi-stage planetary gear combination is usually required. Although the multi-stage design provides a higher transmission ratio, it may bring additional volume increase and efficiency loss.
Speed ​​range: If the equipment needs to adjust the speed during operation, consider using a gearbox that supports variable speed drive, or choose a solution that is compatible with a variable frequency motor.

3. Working environment
The selection of planetary gearboxes must also fully consider the working environment of the equipment, which directly affects its material, sealing and lubrication design.
Temperature range: In high temperature environments (such as metallurgical equipment), the gearbox needs to use high temperature resistant grease and design heat dissipation channels. In low temperature environments (such as outdoor mechanical equipment), the gearbox should use low temperature special lubricants and perform special material treatment to prevent embrittlement.
Humidity and corrosion resistance: In humid or chemical environments (such as water treatment equipment, chemical plants), it is recommended to choose a gearbox with a stainless steel housing or anti-corrosion coating. The equipment sealing system must effectively prevent the intrusion of water vapor or corrosive gases.
Dust and particle environment: In scenes with high dust concentration (such as mining equipment, wood processing equipment), the gearbox requires a high-level sealing design (IP65 or higher) to prevent particles from entering the gear mechanism.
Operation vibration and shock: For equipment that needs to withstand high vibration or shock loads (such as construction machinery or stamping machines), the gearbox should have an impact-resistant design and choose a model with a buffer device.

As China's leading intelligent transmission solution provider, Ningbo Zhongda Leader Intelligent Transmission Co., Ltd. provides global customers with a full range of products and services from brushless DC motors and servo motor drives to high-precision planetary gearboxes, cycloid gearboxes and wave-generating gearboxes with its deep technical accumulation and rich industry experience. Our planetary gearboxes have undergone rigorous research and development and testing, and have excellent performance of high precision, high efficiency and low noise. They can be widely used in industrial automation, robotics, medical equipment and new energy fields. You are welcome to contact us to customize professional solutions that suit your project needs!