How to determine whether the quality of lubricating oil in the gearbox is qualified

To determine whether the lubricating oil quality in the gearbox is qualified, the following aspects can be considered:

Appearance inspection: Observe the color and transparency of the lubricating oil. New lubricating oil usually has a specific color, such as clear light yellow or light brown, and has high transparency. If the color of the oil becomes very dark, black, or cloudy with suspended solids or sediment, it may indicate that the oil quality has deteriorated. For example, after prolonged use, lubricating oil may turn black due to oxidation and contamination, and become turbid when mixed with impurities.

Odor assessment: Normal lubricating oil has its own unique odor. If you smell a pungent, sour, or other abnormal odor from the lubricating oil, it may indicate a change in oil quality. For example, lubricating oil may produce an acidic odor after oxidation or contamination.

Viscosity detection: The viscosity of lubricating oil can be roughly determined through simple methods. Dip your fingers into a small amount of oil, then separate your fingers and observe the oil streaks formed by the oil. If the oil thread is pulled for a long time and not easily broken, it indicates that the viscosity may be high; If the oil filament is short and prone to breakage, the viscosity may decrease. However, this method is relatively rough, and accurate viscosity detection requires the use of a professional viscometer. A significant change in viscosity beyond the specified range of this type of lubricating oil usually indicates a problem with the oil quality, which may be caused by oil aging, dilution, or mixing with other substances.

Moisture detection: Specialized moisture detection test strips or instruments can be used to detect the moisture content in lubricating oil. If the test paper changes color or the instrument displays excessive moisture content, it indicates that too much moisture has been mixed into the oil. Moisture can cause a decrease in the lubrication performance of lubricating oil, accelerate component corrosion, and may also cause oil emulsification, resulting in the oil appearing milky white.

Impurity detection: Take a small amount of oil and place it on clean filter paper to allow the oil to naturally penetrate. If there are more black particles, metal shavings or other impurities left on the filter paper, it indicates that the impurity content in the oil is high. These impurities may be generated by the wear of components such as gears and bearings, or they may be dust mixed in from the outside. Impurities can exacerbate component wear and affect the normal operation of the gearbox.

Acid value and alkali value detection: Acid value and alkali value are important indicators reflecting the chemical properties of lubricating oil, and require the use of professional chemical analysis methods or instruments for detection. An increase in acid value indicates a deeper degree of oxidation of the lubricating oil, which can cause corrosion to metal components; A decrease in alkalinity may mean that the additives in the lubricating oil have been depleted, losing their ability to protect and regulate the oil.

Regular oil quality testing of the gearbox lubricating oil is very important, as it can detect oil quality problems in a timely manner and take corresponding measures, such as replacing lubricating oil or maintaining the gearbox, to extend its service life and ensure its normal operation.