Reasons for the wear of internal combustion counterbalance forklift truck engine cylinder liner
The working environment of cylinder liner is very bad, and there are many reasons for wear. Normal wear and tear is usually allowed due to structural reasons, but improper use and maintenance can cause abrasion wear, abrasion wear and corrosion wear and other abnormal wear.
Wear caused by structural causes
1) The upper part of the cylinder is badly worn by poor lubrication conditions
The upper part of the cylinder sleeve is closed to the combustion chamber.Fresh air and evaporation of fuel dilution and scouring, exacerbating the upper condition deteriorated, in the period just is in dry friction or half dry friction condition, this is the cause of the upper cylinder wear.
2) The acid working environment causes chemical corrosion and the surface corrosion of cylinder liner
The mixture combustion burned in cylinder, it will produce water vapor and acidic oxides, they generate mineral acid soluble in water, combined with the organic acids generated in combustion, the cylinder liner is always working in acidic environment, the corrosion effect on the surface of a cylinder, the piston ring friction gradually be scraped with the corrosion, cause deformation of cylinder liner.
3) Enter the mechanical impurities in the cylinder is the objective reason, which aggravate the wear of the cylinder liner
Because of the principle and working environment of the engine, the dust in the air and the impurities in the oil enter into the cylinder, causing abrasive wear between the piston and the cylinder wall.Dust or impurities reciprocating motion with the piston in the cylinder, as part of the middle cylinder speed of movement is the largest, therefore, intensified the wear of central cylinder.
Misoperation caused the wear
The sealing ring on the piston if failed can lead to engine oil burning.
1) The air cleaner filters efficiency is low.
The function of air filter is to clear the dust and sand in the combustible mixture in the cylinder, in order to reduce the wear of the cylinder, piston and piston ring. If the air filter will not be cleaned for a long time, and the filter effect will be reduced, which will accelerate the wear of cylinder liner.Experiments show that if the engine does not install air filter, the abrasion of cylinder will increase by 6-8 times.
2) Engine operate at a low temperature for a long time
It will cause the combustion badness and produce carbon, the carbon is spread from the upper part of the cylinder liner, and in the reciprocating movement of the piston, the upper part of the cylinder sleeve is caused by severe abrasive wear.
It will cause corrosion wear.Because of the engine temperature is lower, the combustible mixture in the cylinder is not fully mixed burning, and there will have a part of fuel and combustion exhaust gas adhere on the inner wall of the cylinder liner, the formation of acid corrosion will corrode the inner wall of the cylinder liner.
Maintenance of engine lubricants after a certain period of time.Oil usually blackened and lost its due lubrication.Therefore engine lubricants must be replaced after using the specified time and mileage.The long-term use of lubricating oil filter and air filter causes failure, which will not filter the oil and air heavy impurities, dust and grit, etc., causing the cylinder liner to wear seriously.
Improper maintenance caused the wear
If the cylinder liner is not installed in the cylinder liner, if the installation error is present, the center line of the cylinder and the crankshaft are not perpendicular, which can cause abnormal wear of the cylinder liner.
When repairing connecting rod copper sleeve hole deflect, ream connecting rod small copper sleeve, reamer tilt caused by copper connecting rod set of hole deviation, and the center line of the piston pin do not parallel with the center line of the connecting rod little head, forcing the piston tilt to one side of the cylinder liner, can also cause abnormal wear cylinder.
Measures to reduce the wear and tear of cylinders
Due to the low temperature, the oil viscosity is large, the liquidity is poor, and the fuel oil pump is insufficient. At the same time, the oil of original cylinder low down along the cylinder wall after parking, so when starting moment is not working as good lubrication, starting when the cylinder wall wear is greatly increased.Therefore, first start, the engine should be made a few turns, the friction surface will be lubricated before starting. It should be idle running after heat up, it is forbidden to fierce boom oil mouth, start again when the oil temperature up to 40 ℃.The starting point should stick to the low-speed gear and drive a range of miles until the oil temperature is normal before turning to normal driving.
The proper chose and use lubricating oil according to season and engine performance should be chose the best viscosity oil
Do not purchase inferior lube oil freely, and check and maintain the quantity and quality of lube frequently.
Enhance the maintenance of filter and make air filter
The oil filter and fuel filter are in good working condition, which is very important to reduce the wear of cylinder liner.To strengthen the maintenance of ” three filter”, it is an important measure to prevent the mechanical impurities into the cylinder, lighten the cylinder wear, prolonging the service life of the engine. and especially important in the countryside and area which has more sand .Some drivers are absolutely wrong to avoid air filters in order to save fuel.
Keep the engine working temperature
The normal engine working temperature should be at 80-90 ℃.
If the temperature is too low, the engine can’t keep good lubrication, it will increase the wear of cylinder wall, the water vapor inside the cylinder of condenses into water droplets , which dissolve the acidic gas molecules in the exhaust, and generate the acid, which corrode and wear the cylinder wall.Tests show that when the cylinder wall temperature from 90 ℃ drop to 50 ℃, the cylinder wear volume when it 50℃is 4 times as large as 90℃.
Too high temperature can reduce the strength of the cylinder and aggravate the wear, and may even cause the piston over expansion and cause the “bulge cylinder” accident.
Post time: Jul-19-2017