Wear reduction measures for engine piston rings

There are many factors that affect the wear of piston rings, and these factors are often intertwined. In addition, the type of the engine and the conditions of use are different, and the wear of the piston ring is also very different. Therefore, the problem cannot be solved by improving the structure and material of the piston ring itself, we can mainly start from the following aspects: the materials and good matching of piston ring and cylinder liner; Surface treatment; Structural State; Selection of lubricating oil and additives; Deformation of cylinder liner and piston caused by heating during assembly and operation, etc. The following mainly discusses the measures of material, structure and surface treatment. 1. Select materials with good matching performance. In terms of reducing wear, as the material of piston ring, it must first have good wear resistance and oil storage. Generally speaking, it is inevitable that the first air ring wears more than other rings. Therefore, it is especially necessary to use materials that are good at keeping oil film without being damaged. One of the reasons why cast iron with graphite structure is valued is that it has good oil storage and wear resistance. In order to further improve the wear resistance of piston rings, different kinds and contents of alloying elements can be added to cast iron, such as chromium-molybdenum-copper alloy cast iron rings commonly used in engines, it has obvious advantages in wear resistance and oil storage. In a word, the material used for the piston ring is preferably a wear-resistant structure that can form a reasonable soft matrix and a hard phase, so that the piston ring is easy to wear during initial running-in and difficult to wear after running-in. In addition, the material of the cylinder matched with the piston ring also has a great influence on the wear of the piston ring. Generally speaking, when the hardness difference of the grinding material is zero, the wear is the smallest. As the hardness difference increases, the wear also increases. However, at the same time of material selection, it is best to make the piston ring reach the wear limit earlier than the cylinder on the premise that both parts have the longest life, because it is more economical and easy to replace the piston ring than the cylinder liner. For abrasive wear, in addition to hardness, the elastic influence of piston ring material must also be considered. Materials with strong toughness are difficult to wear and have high wear resistance. 2. Structural shape improvement. Over the past few decades, many improvements have been made to the structure of piston rings at home and abroad, and the most remarkable effect has been achieved by changing the first air ring into a barrel surface ring. Because the barrel surface ring has a series of advantages, in terms of wear, the barrel surface ring can float the ring by the oil wedge effect regardless of whether it moves upward or downward to ensure good lubrication. In addition, the barrel surface ring can also avoid the edge load. At present, barrel surface ring has been widely used as the first ring in enhanced diesel engines, and barrel surface ring is also widely used in other types of diesel engines. As for the oil ring, the cast iron oil ring with internal support coil spring, which is widely used at home and abroad, has great advantages. This kind of oil ring itself has good flexibility and excellent adaptability to deformed cylinder liners, thereby maintaining good lubrication and reducing wear. In order to reduce the wear of the piston ring, the cross-section structure of the piston ring group should be reasonably matched to maintain good sealing and lubricating oil film. In addition, in order to reduce the wear of piston rings, the cylinder liner and the structure of the piston should be reasonably designed. For example, the cylinder liner of Steyr WD615 engine adopts a platform mesh structure. During the running-in process, the contact area between cylinder liner and piston ring is reduced, liquid lubrication can be maintained, and wear loss is extremely small; Furthermore, the netting acts as an oil storage tank and improves the cylinder liner's ability to maintain lubricating oil. Therefore, it is very beneficial to reduce the wear of piston rings and cylinder liners. Now the engine generally adopts this cylinder liner structure shape. In order to reduce the wear of the upper and lower end faces of the piston ring, the end faces of the piston ring and the ring groove should maintain appropriate clearance to avoid excessive impact load. In addition, the wear-resistant austenitic cast iron lining embedded in the upper ring groove of the piston can also reduce the wear of the upper and lower end faces, but this method does not need to be fully promoted except for special circumstances. Because its process is difficult to master, the cost is also high.

In an age when custom piston rings is increasingly important, the researchers believe manufacturers should pay close attention to their results.

GUANGZHOU HEARTEN AUTO PARTS CO,LTD. would like to provide our customers with as near perfect protection, as near perfect service as is humanly possible and to do so at the lowest possible cost.'

Regularly improving custom piston rings in accordance with customer feedback is a great way to show your brand listens and cares.