CAD/CAE application in centering EDM machine design
The centering EDM machine can be completed online centering hole processing. Traveling by the high speed line feed mechanism, low speed line feed mechanism, rotating body, lifting body, auto body for baseball, Swing components, such as buffer baffle. The advantage of this approach is: a small device, processing consistency, and efficient processing, process automation, and effective in the elimination round billet rolling wear puncher into a capillary formed by the iron handle. In order to design the machine, the CAD/CAE technology, basing on the conception of global structure, dwelling on selecting motor, 3D modeling with solidworks, dynamic simulation with cosmosmotion, and analysis the key parts using finite element method were presented.
Development of new material and heat treatment for tools ensuring high performance in hot seamless tube rolling
Abstract A new technology has been developed to improve the life of tools used for high temperature steel rolling in seamless tube manufacturing. It is a joint technology combining a new chemical composition and a special heat treatment. The new steel tool material has high Cr, C, and Ni contents compared with those of the conventional tools in order to increase the volume fraction of carbide which increases wear resistance. Through the new heat treatment, the macroscopic distribution pattern of eutectic carbide changes from meshlike to granular form increasing resistance against crack propagation. The validity of the results in the laboratory has been verified on the production line.
A model for predicting heat transfer through gypsum‐board/wood‐stud walls exposed to fire
To facilitate the development of cost-effective and flexible design options there is a need to develop models to predict the fire resistance of wood-frame building assemblies. Such assemblies often derive much of their fire resistance from a protective membrane composed of gypsum board. A simple two-dimensional computer model is presented to predict heat transfer through gypsum-board/wood-stud walls exposed to fire. Input data for the thermophysical properties of gypsum board were measured exploying standard bench-scale tests. Input data for wood were selected from the literature. Small-and full-scale fire resistance tests were conducted on gypsum-board/wood-stud wall assemblies to provide data for the validation of the model. The model is shown to predict heat transfer through these walls rather well.