How to avoid impurities from entering the gearbox when changing oil

To avoid impurities from entering the gearbox during oil change, the following measures can be taken:

Preparation before oil change

Cleaning the exterior of the gearbox: Use a clean cloth or brush to remove dust, oil stains, and other impurities from the gearbox housing, to prevent these impurities from falling into the interior of the gearbox when opening oil and oil holes.

Prepare cleaning tools and containers: Ensure that the tools used, such as wrenches, oil drums, funnels, etc., have been cleaned and free of oil stains, rust, and other impurities. The container used to hold new and waste oil should be dedicated and cleaned and dried in advance to avoid residual impurities contaminating the new oil inside the container.

Oil release process

Choose the appropriate oil discharge time: The oil should be discharged after the gearbox has stopped running for a period of time, so that impurities in the oil can fully settle into the oil pan. It is generally recommended to drain the oil after the gearbox has been shut down for 30 minutes to 1 hour.

Slowly drain oil: When opening the drain hole bolt, do not completely unscrew the bolt, let the oil flow out slowly, and avoid stirring up impurities that have settled at the bottom due to excessive oil flow speed. If the gearbox has multiple oil drain holes, they can be opened one by one to ensure that the oil can be completely drained.

Check the oil drain port: During the oil drain process, pay attention to observing whether there are impurities such as metal shavings and foreign objects in the flowing oil. If any, further inspection and cleaning of the interior of the gearbox is required.

Clean the inside of the gearbox

Use flushing oil: After draining the oil, an appropriate amount of flushing oil can be added to the reducer, and the reducer can be started to run at low speed for a period of time to fully circulate the flushing oil and flush out residual oil and impurities inside. Then drain the flushing oil completely, and this process can be repeated 2 to 3 times.

Wipe internal components: If conditions permit, open the inspection hole or end cover of the gearbox and use a clean cloth or specialized wiping tool to wipe the gears, shafts, bearings, and other components inside the gearbox, removing any oil and impurities attached to them. But be careful not to let the fibers of the wiping tool remain in the gearbox.

Refueling process

Filtering new oil: When adding new oil to the gearbox, a filtering device must be used to filter the new oil. Suitable precision filters or oil filters can be used to filter out small impurities in the new oil, ensuring that the oil entering the gearbox is clean and pure.

Use funnel and protective device: Install the funnel on the refueling hole and set up protective devices around the funnel, such as sealing rings or protective pads, to prevent oil splashing or impurities from falling in during refueling. When refueling, pour it slowly to avoid foam caused by oil flow impact, and observe the oil level to prevent excessive refueling.

Sealed refueling hole: After refueling is completed, tighten the refueling hole bolt in a timely manner to ensure good sealing and prevent external impurities from entering the reducer.

Check after oil change

Check the oil level and quality: After starting the gearbox and running it for a period of time, stop the machine to check if the oil level is normal and if there are any abnormal changes in the oil quality, such as color, odor, etc. If there is any abnormality, the cause should be promptly identified and dealt with.

Check the sealing parts: Check the various sealing parts of the reducer, such as the shaft seal, end cover seal, etc., to ensure that there is no oil leakage. If there is any leakage, it should be repaired in a timely manner to prevent impurities from entering the reducer due to oil leakage.