How to choose a planetary gear reducer suitable for low-temperature environments
To select a planetary gear reducer suitable for low-temperature environments, it is necessary to focus on five core dimensions: material toughness, lubrication adaptability, sealing reliability, structural cold resistance design, and temperature control capability, combined with specific low-temperature operating conditions (temperature range, load type, operating time) for comprehensive selection. The specific details are as follows:
1. Prioritize selecting models with core components made of low-temperature resistant alloy materials
The toughness of metal materials will significantly decrease in low-temperature environments, which can easily lead to brittle fracture. Therefore, the material of core transmission components is the primary indicator for selection. The gears of conventional planetary reducers are mostly made of 20CrMnTi carburizing steel, which is only suitable for environments above -10 ℃. Low temperature working conditions require upgrading to low-temperature resistant alloy steels such as 20CrNiMoA and 40CrNiMoA. These materials can maintain high impact toughness and fatigue resistance even at -40 ℃ or even lower temperatures after carburizing and quenching+low-temperature tempering treatment. The box should be made of ductile iron QT450-10 instead of ordinary gray cast iron. Ductile iron has better low-temperature crack resistance and toughness, which can avoid box explosion caused by stress concentration at low temperatures. In addition, key structural components such as planetary carriers and output shafts need to undergo low-temperature stress relief treatment. Fasteners should be made of stainless steel or high-strength bolts that have undergone low-temperature tempering to prevent connection failure caused by brittle fracture of bolts at low temperatures.
2. Match with low-temperature specialized lubrication system to ensure oil fluidity and lubrication performance
The viscosity change of lubricating oil under low temperature environment directly affects the starting and operating reliability of the gearbox, and the adaptability of the lubrication system should be given special attention when selecting. Firstly, it is necessary to choose a model equipped with fully synthetic low-temperature gear oil, and it is recommended to use poly (alpha olefin) (PAO) or ester synthetic oil. The pour point of these oils can be as low as -40 ℃ or below, and they can still maintain good fluidity in extremely low temperature environments, avoiding problems such as oil solidification and lubrication failure. It is recommended to choose ISO VG 68 or VG 100 viscosity grade to balance low-temperature fluidity and load-bearing capacity. Secondly, it is preferred to choose models with oil circuit constant temperature heating devices, which can maintain the oil temperature at 10 ℃ -20 ℃ through a thermostat, ensuring that the oil quickly forms an effective oil film during startup. In addition, it is necessary to check the insulation design of the lubricating oil tank. Some high-end models will install insulation layers on the outside of the oil tank to reduce heat loss in low-temperature environments.
