机械设计外文文献翻译、中英文翻译、外文翻译

外文原文：

Mechanical design

According to user requirements of special mechanical working principle, structure, movement, power and energy transmission, various parts of the material and shape size, lubrication methods for design, analysis and calculation and mechanical design

Translate them into a specific description to be made based on the workingprocess. Mechanical design is an important part of mechanical engineering, machinery is produced in the first step, is to determine the mechanical properties of the main factors. Mechanical design goal is: in various limited conditions (such as materials, processing ability, theory and calculation method of design of the best machinery ), i.e. to make optimization design. Optimization design to consider the many requirements, generally : the best performance, the minimum cost, the minimum size and weight, use the reliability, minimum consumption and the minimum environmental pollution. These requirements are often contradictory, but their relative importance for the mechanical type and use vary. The designer's task is to weigh up one thing against another according to the specific circumstance, take all factors into consideration, make the design of the mechanical optimal comprehensive technical and economic effect. In the past, optimization design depends on the designer's knowledge, experience and vision. As the base of mechanical engineering theory and the value engineering, systems analysis and other new disciplines in the development, manufacture and use of technical economy the accumulation of data, as well as computer application, optimize gradually abandon the subjective judgment and rely on scientific computing. In the service of different industry different machinery, application of different working principle, requires a different function and characteristic. Industrial machinery design, especially the whole and the entire system of mechanical design, must be attached to the relevant industrial technology to form an independent discipline. So the design of agricultural machinery, mining machinery, textile machinery, automobile design design design, ship design, design of pump, compressor, turbine design, engine design, machine design, professional mechanical design branch. However, many of these professional design and many common technologies, such as the analysis and synthesis of mechanisms, and can analysis and calculation, engineering materials, strength of materials, transmission, lubrication, sealing, and standardization, reliability, process optimization. In addition, there are research design work of the inherent law and the rationality of the design methods and steps of the new design methodology. The mechanical design of the general technology and rational design methodology brings together into an independent, comprehensive mechanical design is mechanical engineering practice and education workers are working hard.

A machine quality basically depends on the quality of design. Manufacturing process on the quality of the machine the role, essence is to realize the design required