How to choose low-temperature lubricating oil? Winter gearbox oil selection tips, copy the operation directly in one article

The difficulty in starting the gearbox in winter is usually due to the rapid increase in viscosity or even freezing of ordinary lubricating oil caused by low temperatures, which greatly increases the starting resistance of the equipment. To solve this problem and make the correct selection, you can master the following core tips:

1、 Three core tips for selecting lubricating oil

1. The preferred base oil is "fully synthetic PAO"

In extremely cold environments, it is necessary to choose synthetic gear oil with excellent low-temperature fluidity (such as using fully synthetic PAO base oil). The low temperature resistance limit of ordinary national standard mineral closed gear oil is usually around -15 ℃, while fully synthetic oil can ensure smooth fluidity even in extreme cold conditions of -30 ℃ or even -40 ℃, avoiding equipment jamming.

2. Beware of the trap of "pour point depressants" and pay attention to the viscosity of sports

Don't blindly believe in oil products that have added "pour point depressants". Although pour point depressants can make oil flow reluctantly at extremely low temperatures, their actual viscosity (kinematic viscosity) is still very high, which can cause a significant increase in resistance during the operation of the gearbox. True low-temperature resistant oil requires maintaining a low kinematic viscosity while maintaining a low pour point.

3. Accurately match the brand based on local temperature and rotational speed

Winter temperature should not be lower than -20 ℃: conventional low-temperature gear oils such as SH220/SH320 or VG220 can be used.

Winter temperature should not be lower than -35 ℃: it is recommended to downgrade and use SH150/SH220; If the output shaft speed is above 100 revolutions per minute, 68 gear oil can be used, and below 100 revolutions per minute, 100 gear oil can be used.

Extreme cold environment (-40 ℃ and below): Customized synthetic gear oil that can start at -40 ℃ is required, and the oil must have good resistance to micro pitting corrosion.

2、 Auxiliary measures to address difficulties in starting at low temperatures

In addition to changing the oil product, the following operations and equipment modifications can also be carried out to ensure operation:

1. No load preheating start: Before formal loading, let the gearbox run without load for 10-15 minutes to allow the lubricating oil to flow fully and slowly heat up, reducing the impact of cold start.

2. Installation of external heating device: For cold storage or equipment that has been in extremely cold environments for a long time, an electric heater can be installed near the oil tank to raise the oil temperature to 0-10 ℃, or a heating belt can be configured for the motor to prevent condensation from freezing.

3. Manual turning inspection: Before each start-up, manually turn the input shaft or coupling to check in advance for freezing or jamming caused by poor lubrication.

4. Sealing insulation protection: Low temperatures can cause rubber seals to become hard and brittle. Regular inspections and replacements should be carried out, and canvas or plastic protective covers should be added externally to block the intrusion of ice, snow, and cold air.