General guidlines for low quantity production - DFMA

Q-5. Mention the design guidelines to be followed in low quantity production.

Ans: In any product, manufacturing and assembly cost is a very important consideration. It affects the overall cost in a significant manner. However during the design phase, with some consideration in product design, production cost can be reduced. In case of low quantity production.

Design guidelines to be followed in low quantity production:

During the design phase, it is good to use standard components in design. Because of low quantity production, using non-standard components may significantly increase the cost.
For lower quantity production, worst case tolerance can be used. Providing loose tolerance may reduce part rejection in the inspection phase, hence maximum parts can be approved.
If too tight tolerance is not necessary, then try to provide more tolerance range. Hence, it also eliminates the use of a special finishing process and reduces post processing cost.
In case of low quantity production, selection of suitable manufacturing processes is limited. Hence, it’s better to decide the manufacturing process in the design phase and design component as per manufacturing process.
Based on design requirement and quantity of production, material is selected. Selection of material also plays an important role in manufacturing process sequence.
Based on design and material requirement, the manufacturing process chooses such a way that allows for low quality production at less cost.
If possible, modular design should be used. It reduces various costs like quality control cost, service and maintenance cost.
In the case of assembly, multi purpose parts should be designed. Hence, it reduces manufacturing cost and also, using the same parts and tools, tooling cost and time reduces.
Eliminate the use of automated systems (like automated welding, automated assembly) if possible. Because automation systems in low quantity production significantly increase cost, and also need to configure systems for production. For low quantity production, designers should consider manual or semi automated systems for manufacturing and designing products that are easily manufactured using manual machining.
Designers should avoid complex geometry in design. Part should design such that it can easily be manufactured by easily available standard machines and standard tools.

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