Process Research And Design Of Aluminum Alloy Connecting Rod For Small Gasoline Engine

The connecting rod is one of the key parts in the engine and compressor,and the stability and reliability of the connecting rod play an important role for the engine.Due to advantages of the light weight and the high strength of the aluminum alloy material,the application of aluminum alloy connecting rod has been widely used in the small gasoline engine.However,nowadays the design and manufacturing technology of aluminum alloy connecting rod in our country still stay in a low stage,the production efficiency and the product quality needs to be improved and enhanced urgently.Based on the research on aluminum alloy connecting rod in past years,this thesis tries to solve the problems associated to assembling,eccentric wear and aluminum chips which appear in the process of connecting rod assembly to the engine.Consequently,the structure of CAP-1 aluminum alloy connecting rod is optimized,and a kind of processing technology leading to high quality connecting rod is proposed.1.The characteristics of structure and process for aluminum alloy connecting rod of small gasoline engine are analyzed.Then,innovation design of oil tank,rod cover and the hole of elastic pin for the rod is suggested too effectively solve the problems of assembly,eccentric wearing and aluminum chip.As a result,the process of aluminum alloy connecting rod can be arranged more effective.Meanwhile,quality of the aluminum alloy connecting rod is improved remarkably.2.Study on casting process of aluminum alloy connecting rod is focused on.The casting process is improved by controlling the hydrogen content of aluminum water solving the problem of the porosity of aluminum alloy.Through the reasonable arrangement of heat treatment furnace,the waiting time of solid solution treatment furnace to the cooling water furnace is shortened,and the heat treatment is optimized.The design suggested improves the mechanical properties of the aluminum alloy connecting rod.3.Research and improvement of machining process and tooling is also realized in this thesis.The processing technology meeting with the principles of datum uniform,rough and fine finishing machining separation are proposed.The design of adding fixed position and multi-direction movable clamping head realizes the clamping position matching with the main position respectively.4.The gauge is developed to rapidly online detect the parallelism and center distance of aluminum alloy connecting rod in high efficiency.Because the measurement relies on three-coordinate measuring instrument,it consumes much time.The proposed design can improve the production efficiency distinctively,so inspection on the connecting rod can be more frequent and reliable.The thought of this thesis derives from the exact production line.What this research achieved can provide great reference for the design of similar aluminum alloy connecting rod and the process of mass-production.