资源描述
附录The role of linkThe role of the piston rod to withstand the force passed to the crankshaft, and to the rec -iprocating piston motion into rotary crankshaft motion. Body by the connecting rod connec -ting rod, connecting rod cap, connecting rod bolts and connecting rod bearing and other parts, connecting rod connecting rod body and the connecting rod cap into a small head, sha -ft and connecting rod. Connecting rod small end is used to install the piston pin to connect the piston. Connecting rod is connected with the crankshaft rod journal. Generally made of separate type, and cut half of the known link shaft cover, both by the connecting rod bolts in -to one. Installed in the connecting rod connecting rod bearing hole in the seat, and crank mounted on the rod journal and together, the engine of the most important one with the vice. Used mainly by run whte gold alloy, copper-lead alloy and aluminum alloy. Linkage in both ends of the hinge with the active and driven components to transmit motion and power bars. For example, in power machinery and reciprocating piston compre -ssor with a piston and connecting rod to crank. Mostly steel rod, the main part of the multi -section-shaped or round, both ends of the hole, hole fitted with bronze bushings or needle bearings for the load axis constitute hinge pins. Automobile engine connecting rod is an imp -ortant part, which connects the piston and crank shaft, its role is to piston reciprocating movement into rotary crankshaft motion, and the force acting on the piston to the crankshaft output power to pass. Link at work, in addition withstand the pressure generated by gas com bustion, but also to withstand the vertical and horizontal inertia force. Therefore, the connec -ting rod in a complex state of stress at work. Both subject to alternating tension and compre -ssion stress, but also by the bending stress. The main damage to the rod form of fatigue frac -ture and excessive deformation. Usually the site of fatigue fracture in the connecting rod on the three high-stress areas. Working conditions require connecting rod connecting rod has higher strength and fatigue resistance; and requires a sufficient rigidity and toughness. con -necting rod in its traditional materials processing technology commonly used 45 steel, 40Cr or 40MnB other quenched and tempered steel. Automobile engine connecting rod is the important parts, it connects the piston and crankshaft, and its function is to change the reciprocating motion of the piston to the rotary motion of the crankshaft, and the role of the force on the piston to the crankshaft output po -wer. The connecting rod in work, except under pressure from the gas combustion chamber, and bear the lateral and longitudinal inertial force. Therefore, the connecting rod in a com -plex stress state work. It is influenced by both the alternating compressive stress, and again by bending stressThe main damage form is connecting rod fatigue fracture and excess deformation. Usually the fatigue fracture of the parts of the connecting rod is three high stress area. The connecting rod working conditions demand connecting rod with high strength and antifati -gue performance; And with adequate rigidity and toughness. The traditional processing technology of the material in connecting general use 45 steel, 40 Cr or 40 MnB etc, but now the tempering steel foreign widespread USES advanced connecting rod cracking (conrod fracture splitting) processing technology requirements brittleness is bigger, hardness higher, therefore, the German auto enterprise production of new materials for connecting rod C70S6 high carbon micro alloy steel, not the SPLITASCO series forging steel, frACTIM forging steel and S53CV-FS forging steel etc (above all on German din standards). Although have the high strength steel, but on the stress concentration is very sensitive. So, in the connect -ing rod appearance, transition round, etc, must strictly requirements should also pay atten -tion to the surface processing quality in order to improve the fatigue strength, otherwise the application of high strength steel alloy and cant achieve expected fruit. The connecting rod processing process is: two end-small head widening coarse grin -ding size head two end-pull the connecting rod size head side face positioning and pull the connecting rod cover two end face and stem two end corner-pull small head two CuLa bolt cant and seat surface, pull matching, to play literally heavy convex mesa and cover position -ing and thick boring side under stem semicircle and corner and small head, thick boring hole on pole, small head size hole and semicircle head hole corner-cleaning parts and parts inspection, demagnetism, fine milling bolt seat surface and R5 arc-milling broken rod, cover -small head hole two oblique end plane on the corner and fine grinding connecting rod rod body two end-processing bolt hole-bars, to cover the junction plane and corner-to mate stem and cleaning matching cover burr and matching stem rod cover cover face detection with precision and manual assembly tightening bolts and cover and print stem and thick boring, matching mark big hole on both sides and corner-half fine boring hole and fine boring big small head bushing apparatus-inspection big head and fine boring hole small head bushing precision apparatus and pressure into the small head hole bushings, weighing to heavy-fine boring hole big head, small head bushing hole-and eventually finished product inspection and cleaning rust. The connecting rod body and cover thickness different, improve the processing man -ufaturability. The connecting rod cover thickness for 31 mm, than the connecting rod rod thickness of 3.8 mm, cover unilateral small two end precision products demand is not high, but one processing and into. Due to the small processing, cooling conditions, make process -ing vibration and grinding burns not easy the creation. The connecting rod rod and cover the assembly to end does not exist, it is not the same problems connecting rod ends the fine grinding dont need to be in after the assembly, can be in the bolt hole before processing. Bolt hole, bearings to end of the position precision machining precision can be directly guarantee, and wont fertilization grinding the influence of accuracy. The connecting rod small head two end face and a narrow by cant plane composition. This kind of wedge design can increase its confined area, in order to improve the strength of the piston and rigidity. In the processing, and general connecting rod more than cant processing and small head hole two ramp Angle pouring process; By increasing the positioning and parts of the pressure head orientation accuracy to avoid bushing pressure partial happens, but actually increased the pressure bushing process the difficulty of the processing. Take the mouth with inclined surface. The connecting rod joint surface structure sort is more, there are flat and oblique incision incision, and the keyway form, jagged and take the mouth. The connecting rod for the mouth with inclined joint surface. Finishing the benchmark is adopted in the product orientation method and clearance design position datum. The connecting rod rod and assem -bly processing, the stem seal face, little head surface and side, big head lateral processing localization way; In the bolt hole to check the mouth with the connecting rod surface treat -ment working procedure of processing, using a cover for its end, bolts two seat surface, a bolt a side localization method of processing. This repetitive positioning precision and reliability of the localization, the clamping method, can make the part deformation small, easy to operate, can general from rough machining precision to the in each procedure. Because the locating datum unity, make each working procedure of the anchor point size and position and keep the same. All of these processes, ensure stable machining accuracy provided the good condition.
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