Why does the lubricating oil always foam during gear processing?
December 24, 2021
With the continuous development of various industries, the application of gears is very wide, and the automobile industry uses a lot of gears. However, it is not so easy for gear factories to produce gears. There are many large and small problems that plague gear factories. Among them, the problem of foam produced by lubricating oil in gear production is the most troublesome. So how should gear factories solve the bubble problem?
Why does lubricating oil foam during gear production? The setting of the fuel tank is unreasonable, and the oil pollution and the quality of the oil drop into the air-during the operation cycle of the mechanical equipment, the air is brought into the middle of the oil to produce foam. Incoming air is the smallest amount of air distributed in the entire fuel tank with very small bubbles. Incoming air and foam are handled differently and are usually a complete separation problem. It is more serious than foam and can cause pump cavitation, oil oxidation, etc. Air entering is different from dissolved air. Usually the oil contains 8%-12% of dissolved air. In various oils such as industrial Gear Oil, engine lubricating oil, hydraulic oil and rail oil, it contains various additives of different properties. Most of these additives are polarized compounds and have Surface activity promotes foaming of oil products. During the use of lubricating oil, some gums, asphaltenes and sludge residues generated by oxidation and decomposition can promote the increase of foaming. Due to the deterioration of the oil during use, the surface tension of the oil decreases, which also promotes the generation of foam. What is the hazard of lubricating oil foaming? The compressibility of the lubricating oil is large, and the efficiency of the oil pump is reduced, which makes the oil supply abnormal or the oil supply system has air resistance. As a result, the friction part is cut off, causing wear or sintering. Foam will cause the lubricating oil to overflow from the breathing hole and the oil filling pipe or display a false liquid level in the oil level indicator, resulting in insufficient oil supply. The contact area between lubricating oil and air becomes larger, which promotes the accelerated oxidation and deterioration of oil products and shortens the service life. The lubricating oil filled into the container is reduced, so that the time for the foam to disappear is prolonged. If used in a hydraulic machine, the pressure of the hydraulic system will be unstable, the cooling capacity will be reduced, the power and speed foam will be affected, the surface tension of the lubricating oil will drop, the extreme pressure contact surface of the equipment will not form an oil film, the gear surface will be pitted, and serious poor lubrication may be possible. Cause breakage. Is there any way for gear factories to control foam? Methods to eliminate foam are generally divided into physical and mechanical anti-foaming and chemical anti-foaming. Physical and mechanical anti-foam method: (1) Eliminate impurities Dust and powder are the main culprits that cause gear lubricating oil to foam out of control. Not only the dust itself, but calcium also adsorbs anti-foaming agents. Check the filter and respirator for particles. Install the filter in a dusty place. The exhaust port is downward to avoid dust collection, especially in dusty conditions. Remove or reduce the substances that cause lubricating oil to foam. The entire lubrication system should be carefully cleaned before loading or changing the oil, especially to remove the residues of the metal cleaning agent used for cleaning.
(2) Control the amount of air entering the fuel tank Avoid a large amount of air entering the fuel tank. The air that enters is released to the fuel tank. The gears in the system rotate and squeeze to produce bubbles. If the fuel tank is poorly ventilated, the bubbles generated by the gear agitation cannot be eliminated.
(3) The oil level is too high or too low. The correct oil level is critical. If the oil level is high, moving parts will bring in air. Low oil level will bring bubbles to the liquid surface. The measures to be taken are to observe the oil gauge regularly to ensure the oil level and prevent sudden temperature changes.
(4) Fuel tank design and maintenance A clogged filter is a cause of air ingress. The filter should be installed correctly, and the filter or respirator should be checked regularly for damage, blockage and insufficient filtration, and regular replacement should be carried out. Basically ensure that the bubbles have enough time on the surface to facilitate release.
(5) Oil temperature change The environment and the operation mode of the equipment are the main reasons for the rapid changes in the temperature of the lubricating oil. The system can increase the cooling device according to the actual situation to control the oil temperature, and prevent the sudden temperature change from causing the oil quality to drop and foam. Chemical defoaming method: Use defoaming agent and Anti-foaming Agent to carry out a chemical reaction to burst the foam and achieve the purpose of defoaming. Chemical defoaming is currently a faster and more effective method. At present, most gear factories use gear oil defoamers. Gear oil defoamers can deal with foam problems. Gear oil defoamer has fast defoaming speed and lasting foam suppression, which can solve your foam problem.
