Factors to be considered while Designing Machine
When the designer designs the elements of the machine or the complete machine, they have to consider several important parameters. Here are some of the important factors to be considered while doing machine design:
1) Cost: Cost has always been the major factor of consideration while designing the machine elements or machine and in this age of competition it has become more important. The best machine design is the one which helps get the finished product with all the major functionalities and highest possible quality at the lowest possible cost. Gone are the days when expensive and bulky materials were used for making the machine elements.
2) High output and efficiency: Earlier machines used to be very heavy and consume lots of power. Now the trend is of full functional machines consuming low power and giving high output in terms of the number of the of products manufactured. Some computer controlled machines can manufacture the components very fast and are highly efficient.
3) Strength: The machine elements or the machine should be strong enough to sustain all the forces it is designed for so that it is not damaged or permanently deformed during its life time. Right at the time of the designing the machine the designer should consider the force machine can be applied to and consider all the relevant factors that could affects its life.
4) Stiffness or rigidity: The machine should be rigid enough so that under the effect of applied forces for which it is designed there is no deformation of the machine or machine elements beyond the specified limits. If there is excessive deformation, there are chances of the failure of the machine elements and the whole machine.
5) Wear resistance: Wear is the removal of the material from the metallic surface when two surfaces rub with each other. If there is more removal of the material, the component will become weaker and eventually break. The wear of the contacting surfaces can be reduced by the lubrication of the surfaces, increasing the strength or the hardness of the working surfaces. The effect of wear can also be reduce by increasing the surface, so that during the lifetime of the mating machine elements they will not fail even if there is some wearing between them.
6) Lubrication: Lubrication between the two mating surfaces of the elements of the machine help reducing friction between them and wearing of the two surfaces, which results in the increase in life of the components of the machine.
7) Operational safety: For the safety of the operator of the machine, the hazard producing things from the machine should be eliminated and the design should confirm to the safety codes.
Book: Machine Design by Dr. P. C. Sharma and D. K. Aggarwal