英语翻译The complete design of a machine is a complex process.Th

英语翻译
The complete design of a machine is a complex process.The designer must have a good background in such fields as static,kinematics,dynamics,and strength of materials,and in addition,be familiar with the fabricating materials and processes.The designer must be able to assemble all the relevant facts,and make calculations,sketches ,and drawing to convey manufacturing information to the shop.
One of the first steps in the design of any product is to select the material from which each part is to be made.Numerous materials are available to today’s designers.The function of the product,its appearance,the cost of the material,and the cost of fabrication are important in making a selection,a careful evaluation of the properties of a material must be made prior to any calculations.
Careful calculations are necessary to ensure the validity of a design.Calculations never appear on drawings,but are filed away for several reasons.In case of any part failures,it is desirable to know what was done in originally designing the defective components.Also,an experience file can result from having calculations from past projects.When a similar design is needed,past records are of great help.