A successful manufacturing project requires an adequate planning and execution, and a key factor to achieve this is to ensure that the products that will be manufactured are designed having in mind the principles of DFM (Design For Manufacturing).
Design For Manufacturing is the method of design which has for purpose to reduce and ease the manufacture of the product and its assembly. It has for aim to reduce the amount of components, resulting into cost reduction and minimisation of the complexity in the manufacturing process.
DFM should be deeply embedded in the design process, as it will help to build the product at the lowest price possible, resulting in a higher revenue. This process must involve the selection of a diverse range of raw materials, manufacturing and surface finishing processes, even different packing options. In simple words it might be the “What if…..” game in the design scenario, this process creates critical questions to the designers and industrial engineers such as What to add? or What can we reduce or remove?
The 10 main rules for DFM according to Tien-Chien chang, Richard A Wysk, and Hsu-Pin Wang are:
1) The reduction of the total number of parts:
Less parts implies less purchases, inventory, handling, processing, development and times, equipment usability, assembly difficulty, service inspection, testing, etc.
2) The development a modular design:
The use of modules in a product reduces and simplifies the manufacturing activities including: inspections, tests, assembly, redesign, maintenance, service and so on.
3) Use of standard components:
Standard components are cheaper and easier to get than custom made components.
4) Design parts to be multi-functional:
By having some multi-functional parts the amount of items needed to assembly reduces, this is related to the rule number 1).
5) Design parts for multi use:
Designers should create several parts different parts to have multiple uses. These parts can have the same or different functions when used in different products.
6) Design for ease of fabrication:
Selection of the optimum combinations of materials and production processes to minimise manufacturing costs.
7) Avoid the use of separate fasteners:
The use of separate fasteners increase the manufacturing cost, these should be replaced by using using tabs or snap fits. If fasteners have to be used, then some guides should be followed for selecting them. Minimize the number, size, and variation used; also, utilize standard components whenever possible.
8) Minimise Assembly Directions:
All parts should be assembled from one direction. If possible, the best way to add parts is from above, in a vertical direction, parallel to the gravitational direction (downward). In this way, the effects of gravity help the assembly process, contrary to having to compensate for its effect when other directions are chosen.
9) Maximise compliance
Errors can occur during insertion operations due to variations in part dimensions or on the accuracy of the positioning device used. This faulty behaviour can cause damage to the part and/or to the equipment. For this reason, it is necessary to include compliance in the part design and in the assembly process.
10) Minimise Handling:
Handling consists of positioning, orienting, and fixing a part or component. To facilitate orientation, symmetrical parts should be used when ever possible. If it is not possible, then the asymmetry must be exaggerated to avoid failures.
In C2W we offer Product Design Services, we pride ourselves on the ability to take virtually any idea at any stage in its development, from concept to technical evaluation and providing the client a fully developed design regardless of its purpose while doing so at a fraction of the cost our western-based rivals can offer. All our Design services are critically focused in DFM, having in mind the aims to reduce manufacturing costs, remove complexity and create manufacturing to make sure that your Quality needs are met.
Within this stage, we typically produce prototypes to verify the design against an agreed test plan and regulatory standards, before commitment to major capital expenditure.