The failure of the chain drive is mainly manifested by the failure of the chain. The main failure forms of chains are:
1. Chain fatigue damage:
When the chain is driven, since the tension on the loose side and the tight side of the chain is different, the chain works in a state of alternating tensile stress. After a certain number of stress cycles, the chain elements will be damaged due to insufficient fatigue strength, the chain plate will undergo fatigue fracture, or fatigue pitting will occur on the surface of the sleeve and roller. In a well-lubricated chain drive, fatigue strength is the main factor that determines the chain drive capacity.
2. Magic damage of chain hinges:
When the chain is driven, the pressure on the pin and the sleeve is large, and they rotate relative to each other, which causes wear on the hinge and lengthens the actual pitch of the chain (the actual pitch of the inner and outer links refers to the two adjacent ones). The center distance between rollers, which changes with different wear conditions during use), as shown in the figure. After the hinge is worn, since the growth of the actual pitch mainly occurs in the outer link, the actual pitch of the inner link is almost unaffected by wear and remains unchanged, thus increasing the unevenness of the actual pitch of each link, making the transmission More unstable. When the actual pitch of the chain stretches to a certain level due to wear, the meshing between the chain and the gear teeth deteriorates, resulting in climbing and tooth skipping (if you have ridden an old bicycle with a severely worn chain, you may have had this experience) , Wear is the main failure form of poorly lubricated open chain drives. As a result, the life of the chain drive is greatly reduced.
3. Gluing of chain hinges:
Under high speed and heavy load, it is difficult to form a lubricating oil film between the contact surfaces of the pin and the sleeve, and direct metal contact leads to gluing. Gluing limits the ultimate speed of the chain drive.
4. Chain impact breakage:
For chain drives with large slack edges due to poor tensioning, the huge impact generated during repeated starting, braking or reversal will cause the pins, sleeves, rollers and other components to fail to fatigue. Impact breakage occurs. 5. The chain is broken due to overload:
When the low-speed and heavy-loaded chain drive is overloaded, it will be broken due to insufficient static strength.
Post time: Jan-03-2024