The Oil filter element is the core protective component of the engine lubrication system,which is divided into two types:rotary shell type and built-in paper core type.When the engine is running,the oil circulates through the filter,intercepting metal debris,carbon deposits,sludge,and gum impurities in the oil,and delivering clean lubricating oil to the crankshaft,connecting rod,bearing shell,piston,and valve mechanism,playing a role in lubrication,cooling,cleaning,and buffering.

　　There are two key valves inside the machine filter:**check valve(one-way valve)**,which is closed after shutdown to retain the oil in the filter element and oil passage.At the moment of starting the refrigeration unit,the oil pressure is immediately established to prevent dry grinding and damage to the bearing shell;**The bypass safety valve**automatically opens when the filter element is severely clogged or the oil resistance is too high.The oil flows directly without passing through the filter paper,ensuring that the engine will not shut down due to oil loss.However,impurities are no longer filtered at this time,which belongs to the emergency protection mode.

　　The engine oil enters through the peripheral holes of the base,passes through filter paper,and flows back to the engine oil passage through the central hole.Heavy load and high dust conditions in mines result in rapid oil pollution and increased filter load.Filter failure will not trigger a separate pop-up alarm.Typical phenomena include:the oil pressure warning light is on,the cold start engine makes abnormal metal noises,the oil consumption increases,the oil quickly turns black and sludge increases in a short period of time,causing severe damage to the bearing and holding the shaft.The engine is directly overhauled,and the maintenance cost is tens or hundreds of times higher than that of the filter element.

　　The machine filter is a disposable maintenance part,and it is prohibited to clean and reuse it.Rinsing it will damage the filter paper fibers and completely lose its filtering ability.Many construction sites use inferior machine filters to save money,which ultimately leads to significant engine damage.Valuing the quality of the filter and replacing it on time is the most cost-effective way to protect the engine.