Threaded interference fitting method and threaded interference fitting structure for turbine impeller and rotary shaft

Abstract

The invention relates to a threaded interference fitting method and a threaded interference fitting structure for a turbine impeller and a rotary shaft. Through reasonable design of a threaded connecting structure and process diameters of a titanium aluminum turbine impeller and a 42CrMo rotary shaft, machining of titanium aluminum turbine impeller inner threads and a titanium aluminum turbine impeller matching end face and 42CrMo rotary shaft outer threads and a 42CrMo rotary shaft matching end face, threaded assembling of the titanium aluminum turbine impeller and the 42CrMo rotary shaft is achieved by heating a threaded connecting part of the titanium aluminum turbine impeller or cooling a threaded connecting part of the 42CrMo rotary shaft, blind holes of connected turbine rotary shafts are machined, elastic cylindrical pins are fitted in the blind holes, and other parts of the connected turbine rotary shafts are machined according to structural parameters of turbine rotary shafts. The advantages of threaded connection and interference fitting are combined, durable and reliable connection of the titanium aluminum alloy turbine impeller and 42CrMo alloy rotary shaft, and the connection strength requirements of the booster turbine impeller and the rotary shaft are satisfied.

Description

technical field [0001] The invention belongs to the technical field of mechanical design and manufacture, and in particular relates to a thread interference connection method between a titanium-aluminum supercharger turbine impeller and a rotating shaft. Background technique [0002] The turbine shaft is one of the core parts of the turbocharger, usually connected by the turbine wheel and the shaft. At present, the turbine impeller of diesel engine turbocharger for vehicles is generally made of cast nickel-based superalloy K418 material (the material density is 8.0×10 3 kg / m 3 ), the shaft is made of 42CrMo alloy steel. For the turbocharger turbine impeller made of K418 material and the shaft made of 42CrMo alloy steel, the friction welding process can be used to realize the reliable connection between the turbine impeller and the shaft to form the turbine shaft. However, due to the high density of K418 material, the moment of inertia of the turbine impeller made of K418 ...

AI Technical Summary

Problems solved by technology

However, due to the high working temperature of the connection between the turbine impeller and the shaft, the strength of the interference connection between the titanium-aluminum alloy turbine wheel and the 42CrMo alloy shaft will decrease with the increase of the use time of the supercharger. It is difficult to ensure the long-term stability of the connection strength between the titanium-aluminum alloy turbine impeller and the 42CrMo alloy shaft

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