Assembly Technology of Engine Linkage Components

Linkage components are one of the most important parts for automobiles and engines. The quality of the connection directly affects the quality of the whole machine and the whole vehicle. The following is mainly about the assembly of connecting rod components.

 

 

Significance of Linkage Components Assembly

The linkage components assembly is composed of linkage on transmission, linkage cover, linkage bolt and linkage bearing. One end of the linkage is a small head for installing a piston pin to connect the piston, and the other end is a large head to connect with the linkage journal of the crankshaft. The small end of the linkage is provided with a bronze bushing, which is sleeved on the piston pin. There is a certain gap on the side of the small head to prevent it from being stuck at the pin hole seat when working. An oil collecting hole is glued above the small end of the linkage and the bush, connects with the oil groove on the inner surface of the bush. When the diesel engine is working, the splashed oil falls into the hole to lubricate the piston pin and the bush. The linkage bolt is a special bolt used to connect the linkage cover and the linkage into one. The linkage bearing bush is installed in the big end hole seat of the linkage and the linkage journal on the crankshaft. It is one of the most important matching pairs in the engine. It is necessary to assemble the linkage assembly, which is of great significance to reduce the occurrence of engine failure.

 

 

Assembly of Linkage Bolt and Self-locking Nut

The connection of the big rods end to the crankshaft linkage journal is the most important combination of diesel engines. Linkage bolts often withstand alternating loads. It is often made of high-quality alloy steel or high-quality carbon steel. After tempering and heat treatment, it cannot be replaced with ordinary bolts to avoid fatigue fracture due to insufficient strength. During use, attention should be paid to check the fastening condition to prevent loosening. Regularly dismantle and check it for cracks, excessive elongation, etc. If necessary, replace it in time.

 

When installing the linkage bolts, a comprehensive inspection of the linkage bolts must be conducted to ensure that it has no necking phenomenon and the thread is qualified before use. It should be noted that the linkage bolt and linkage nut are inch threads. When installing, a thread of engine oil should be applied to the thread, and the nut should be smoothly screwed onto the bolt. During assembly, the linkage bolts should be alternately and evenly tightened to the specified torque to avoid accidents such as breakage of the linkage bolts. To prevent the bolt from loosening, use cotter pin, locking piece or locking wire at the linkage to lock it firmly.

 

At present, self-locking nuts are widely used in engines. When tightening the self-locking nut, the bolt gives the nut a pull force, and the support plane of the nut produces a reaction force. Because the bottom of the nut is concave and the average diameter of the support surface is larger than the average diameter of the thread, the bending moment is generated, which makes the upper end of the nut slot bend inward and tighten and self lock.

 

In addition, the slotting of the nut is biased to one end of the regular hexagon, making the thickness of the slotting at the rear end greater than the front end. The tightening amount of the front end is greater than that of the rear end, making the nut more resistant when turning in the loosening direction, resulting in the second self-locking effect. After repeated tightening and loosening, the self-locking ability of the self-locking nut will be reduced. Therefore, the self-locking nut of the linkage should be replaced during maintenance.

 

 

In short, the assembly process of the linkage components, the assembly process of the linkage bolt and the self-locking nut have a great influence on the assembly quality of the whole engine.