Papers by Author: Yao Bing Wei

Abstract: Mechanical model of crankshaft and connecting rod mechanism of reciprocating compressor was built. Then the order of stress was obtained every ten degrees while crankshaft turning. The larger stress of crankshaft initial turnings was utilized to calculate the whole model and the unreliable region and destructive working condition then was determined. The situation was simulated with ANALYS and the static characteristics, i.e. stress and strain, of the crankshaft was also obtained. The simulated results testify the analysis and the results of the paper have great value for reference when designing crankshafts.

Abstract: A group of geometrically similar elements is automatically generated layer by layer around the tip of crack. By taking advantage of the same stiffness and similar mass of similarly shaped elements, the combined stiffness matrix and combined inertia matrix in area
can be expressed by the displacement row matrix of outer polygon. The global stiffness matrix will be obtained if the combined stiffness matrix and combined inertia matrix of area
are assembled to those of another elements according to corresponding nodes. The small set of generalized coordinates can be obtained through solving the equation, and then the dynamic stress intensity factor of crack will be obtained. The three points bending with single crack and shearing model with double cracks in explosive loading were calculated with finite geometrically similar element method.

Abstract: The application of regular blanking for brass under extra-low cycle rotating bending fatigue was studied. The experiments of rotating bending fatigue have been made in special equipment designed by us. Several problems, the relations of the cycle times of fracture, the strain amplitude near the tip of notch and fracture toughness of fatigue to the presetting deflection, the effects of depth and tip radius of notch to the cycle times of fracture, were discussed through the experiments. The formulae of stress amplitude at the tip of notch and fracture toughness of brass to presetting deflection were obtained. The suitable parameters of fracture in rotating bending fatigue for blanking of brass under extra-low cycle times have been proposed.

Abstract: The rotating bending and the inverse rotating bending are the two different forms of fatigue fracture. Some fracture problems for middle carbon steel in extra-low rotating bending fatigue loading are studied in this paper. The experiments of inverse rotating bending fatigue have been made in special equipment designed by us. Several problems, the relations of the cycle times of fracture and the strain amplitude near notch tip to the deflection, the relations of the depth of crack propagation to the cycle times of fracture, are discussed through the experiments. The effects of depth and tip radius of notch to the cycle times of fracture are studied also in this paper. The suitable parameters of inverse rotating bending fatigue fracture model for middle-carbon steel in extra-low cycle times has been proposed.