Imported engine cylinder liner components 'Longevity Method'

Tips to extend the service life of imported engine cylinder liner components:Haixing generator set manufacturerShare it with everyone.

We understand that the service life of the lower cylinder liner assembly depends on the following factors:
First, the quality of the cylinder liner assembly itself;
Second, the installation accuracy of the cylinder liner assembly.Especially when the cylinder liner is a thin-walled semi-finished product, the boring processing accuracy of the cylinder liner and the dimensional and positional accuracy of the body hole are critical;
Third, the quality of related accessories air filters and fuel injectors;
Fourth, daily care and maintenance, especially the control of oil cleanliness and engine temperature, are very important!
Therefore, choosing a good cylinder liner component is only a prerequisite to ensure the normal use of the engine.But its installation, related supporting equipment and maintenance are also extremely critical.

Secondly, we need to know the correctness of the cylinder linerGenerator setWhat are the impacts:
1. Influence of the original body: If the original engine body has metal fatigue damage due to long-term use, resulting in insufficient stiffness or changes in position accuracy, the outer surface of the cylinder liner of the newly replaced cylinder liner assembly will not be in good contact with the inner surface of the cylinder liner hole of the engine body. It will affect the heat transfer of the cylinder liner, causing the thermal load of the cylinder liner, piston and piston rings to be too high (in this case, measuring the temperature with a water thermometer cannot reflect the true temperature of the cylinder liner), and accelerate the carbon deposition of the engine oil in the piston ring groove. and snap ring.Under working conditions, it will be impossible to ensure good sealing performance between the piston, piston ring, and cylinder liner, and early oil leakage will inevitably occur.
2. Influence of boring accuracy: If the processing accuracy of thin-walled semi-finished cylinder liner boring cannot be guaranteed, the clearance between the cylinder liner and the piston will be too large or too small, and the piston ring, cylinder liner and piston will not cooperate well, which will also affect the piston. The sealing and lubrication between rings, cylinder liners and pistons accelerates the wear of cylinder liners and piston rings.
3. Impact of air filter: If an inferior air filter is installed, the engine will inhale a large amount of dust, rapidly wear the cylinder liner and piston ring surface, reduce the piston ring tension, deteriorate the sealing performance, and cause a sharp decline in engine power performance; in particular, If even very small grains of sand are allowed to enter the gap between the engine piston and cylinder liner, it will be enough to strain the cylinder liner and piston rings in microseconds, and even cause the engine running at high speed to have devastating consequences such as broken connecting rods and destroyed body. !
4. Impact of fuel injector quality: Using inferior fuel injectors or not replacing damaged fuel injectors will lead to poor fuel atomization quality, which will affect the normal combustion of the engine and will seriously affect the engine combustion efficiency and the uniformity of each cylinder's work.In particular, the secondary injection will cause the temperature of the engine piston to rise sharply, accelerate the carbon deposition in the piston ring groove, cause snap rings, and affect the service life of the cylinder liner assembly.
5. The impact of oil cleanliness: Using inferior oil filters or not replacing contaminated oil will accelerate the wear of piston rings and cylinder liners.It will also cause the oil nozzle to be blocked by oil impurities and lose its effectiveness in cooling the piston (often there are black and blue marks on the top of the piston), causing the temperature of the piston cylinder liner and piston rings to be too high, causing the cylinder liner assembly to fail.
6. Impact of the cooling system: If there is a problem with the cooling system, the thermal load of the cylinder liner assembly will be too high, especially if the temperature at the top of the piston is too high, it will cause fatal related damage, which will cause the metal on the piston head to be burned and strained. Cylinder liner; it will also cause the engine oil to quickly accumulate carbon on the upper wall surface of the cylinder liner and the piston ring groove, blocking the piston ring, causing the outer corners of the piston ring to scratch the cylinder liner, destroying the lubricating oil film on the inner wall of the cylinder, and easily causing the cylinder liner to slip on the first piston. There are step-like severe wear marks at the top dead center of the ring.
Long-term tests have proven that the stable production of brand original cylinder liner components will not cause excessive engine thermal load.Excessive thermal load is not caused by the quality of the cylinder liner assembly itself, but by other reasons.Excessive thermal load is the reason why the carbon deposits in the piston ring grooves are accelerated and the snap ring causes abnormal wear of the cylinder liner and piston rings and the passage of engine oil.Damage to the cylinder liner assembly is simply the result of excessive thermal load.Excessive thermal load is a common and fatal killer of cylinder liner components.Cause and effect cannot be reversed.Therefore, when replacing a new cylinder liner component, you should check the cause of damage to the original cylinder liner component being replaced.If the replaced cylinder liner component is originally a part and is not a normal replacement due to long-term use, the cause of the damage to the cylinder liner component should be found from the assembly and other systems.If there are problems with other systems and are not eliminated, problems will occur soon after replacing the new cylinder liner assembly.

We need to understand some points to pay attention to when replacing the cylinder liner components of the generator set:
After ruling out that the replaced cylinder liner component is damaged due to other system problems, when it is determined to replace and assemble a new cylinder liner component, special attention should be paid to the following points:
(1) After disassembling the replaced cylinder liner, clean the original body and strictly check its stiffness and position accuracy, especially the concentricity of the cylinder liner hole in the body.If the stiffness and positional accuracy of the original body cannot be repaired, the body can only be updated.The engines of imported excavators are highly reinforced. Most of them use thin-walled cylinder liners, which are easily deformed during installation. The contact area between the cylinder liner hole in the body and the outer surface of the cylinder liner is large. If the concentricity of the cylinder installation hole cannot be obtained, It is guaranteed that it will not take long for major faults such as the breakage of the upper convex ring band of the cylinder liner or the deformation of the cylinder liner to affect the contact and sealing between the cylinder liner and the piston ring, causing abnormal wear and leakage of air and oil.

(2) Ensure the installation quality of thin-walled cylinder liners.In imported excavator engines, such as S6KT, 6D31T, and 6D34T engines, in order to solve the problem of easy deformation of thin-walled cylinder liner press-fit installation, the cylinder liner is often supplied as a semi-finished product with a machining allowance in the inner hole (there is no convex ring belt on the upper part) Positioned straight cylindrical thin-walled cylinder liner, the manufacturer supplies semi-finished products), so that the user can press-fit the cylinder liner and then honing the inner hole of the cylinder liner to eliminate deformation.This requires that the honing of the cylinder liner hole must ensure the accuracy of the inner surface and the concentricity of the cylinder liner hole during maintenance.Otherwise, problems may occur during use.In order to guide users to correctly install thin-walled cylinder liners, IZUMI Company provides the installation and honing process specifications for semi-finished thin-walled cylinder liners (attached).When users assemble semi-finished cylinder liners and do not have qualified boring equipment and skilled maintenance technicians, they must send the boring cylinder to a professional factory with well-equipped boring equipment and skilled boring technicians.The quality of the semi-finished cylinder liner itself is mainly reflected by the cylinder liner material and the shape and position tolerance of the cylinder liner's outer cylinder, while the quality of the cylinder liner hole mainly depends on the technical accuracy of the boring equipment and the boring technician's shape and position tolerance of the cylinder liner hole. , surface accuracy and piston cylinder liner clearance control.By the way, I would like to point out that there are many counterfeit brands of semi-finished thin-walled cylinder liners on the market because the materials do not meet the requirements.In order to ensure the firmness of the cylinder liner installed on the engine body, counterfeit manufacturers adopt methods of increasing the outer tolerance of the cylinder liner.However, this method has no impact on the life of the cylinder liner itself. The result is that it reduces the number of repairs available for the body and greatly shortens the life of the body. The gain outweighs the loss!

(3) Install the piston rings correctly. Do not install the first and second gas rings in a misaligned position or install the first gas ring with the upper and lower sides opposite to each other.Otherwise, serious accidents in which the piston ring is broken and the cylinder liner is scratched will occur soon after the engine is reinstalled and started.

(4) Strictly check and clean the engine cooling system, especially check the working efficiency of the water pump and the tension of the water pump belt.Prevent cooling system failure causing engine overheating.

(5) Replace the contaminated engine oil, clean the oil passage, oil nozzle and air intake passage, and replace the third filter.

(6) Replace the fuel injector, oil pump plunger and oil outlet valve in time.

(7) After starting the engine, the load must be gradually increased from small to large for several hours of running-in.

(8) Before allowing the engine to operate normally after the running-in process, replace the oil filter element again, and loosen the oil pan drain plug to remove the metal chips in the oil after running-in, or replace it with new oil.
In short, the cylinder liner component is a key component in the engine. When selecting it, you must first ensure quality and purchase products with reasonable prices.IZUMI cylinder liner components supplied by the OEM are your best choice for both price and quality.There are many counterfeit IZUMI cylinder liner components on the market. Please choose IZUMI products, because if you choose counterfeit IZUMI products, in addition to short service life, frequent replacement will cause associated damage to the cylinder liner mounting holes in the engine body, and may even cause irreparable consequences.When replacing the cylinder liner component, it is necessary to ask a technician with real experience in repairing imported construction machinery engines to find out the cause of damage to the replaced cylinder liner component. In particular, check the technical condition of the body and the position accuracy of the cylinder liner hole to eliminate the cause of the cylinder liner component. If there are other reasons for damage, carefully replace the cylinder liner assembly.For the supplied semi-finished thin-walled cylinder liners, the inner hole must be installed and honed strictly in accordance with the process specifications to ensure the quality and concentricity of the inner surface of the cylinder liner.After replacing the cylinder liner assembly, the contaminated engine oil must be replaced, the impurities in the oil passages, oil injectors and oil pans must be cleaned, the air filter, diesel filter and oil filter must be replaced, the cooling system must be checked and adjusted, and the replacement must be processed with high precision and The fuel injector with good thermal stability ensures the quality of fuel atomization.Be sure to control diesel engine overheating!After the engine is reassembled, allow the diesel engine to run in for several hours from small to large loads.By ensuring the quality of the cylinder liner components from the purchasing process to the repair, assembly, use and maintenance processes, the engine will be able to work healthily and long-term and perform efficiently.