Design for Manufacture
Design for Manufacture (DfM)is focused on optimizing the manufacture of the design to meet a certain criteria. This optimization takes the form of reducing waste, costs, labor, and production time, as well as reducing product development time.
By understanding and identify these criteria earlier on in the design process, the cost of making changes during production can be eliminated or reduced.
DfM
Design for Materials
Designing in relation to the materials used to manufacture the design. A designer might consider:
The availability of certain materials locally. Locally available materials might be cheaper, have a lower carbon footprint, or more directly benefit local suppliers.
The environmental impact of using sustainable materials.
The physical and mechanical properties of a material might be integral to the performance of the product. As such, the form or manufacture of the product would be dictated by the material's properties.
The property of glass being non-reactive makes it ideal for food and drink containers. The concave base and rounded edges increase the resistance to impact. Thus, most glass bottles have a concave base
In New Mexico, USA, adobe is used as a building material. Available locally, its unique properties make it ideal for hot dry climates. The material dictates the type of architectural forms that can be made with it.
The recycled PET plastic used to make this Patagonia fleece jacket was selected as part of the company's sustainability initiatives. Design and manufacturing techniques needed to be matched with the material.
DfP
Design for Process
Designing to enable the product to be manufactured using a specific manufacturing process, for example, injection moulding.
A designer might consider:
The type of production systems and equipment available.
The type of materials that a particular production equipment would require.
The types of fasteners and joints that would be used.
Ways the design can be optimized to reduce manufacturing time and errors
Designing spoons for injection moulded plastic would require a different process than metal cast spoons.
DfA
Design for Assembly
Designing taking account of assembly at various levels, for example, component to component, components into sub-assemblies and sub-assemblies into complete products.
DfA is primarily focused on reducing the cost of assembly. These costs would include costs related to parts and labor.
A designer might consider:
Ways to simplify the design so that it requires fewer parts and processes
How to make parts easier to grasp and assemble in order to assemble quickly and accurately
Selecting fasteners that don't require special tools
Limiting the number of unique parts and fasteners
Snap-fit fasteners can reduce assembly time and associated costs.
In the example, notice how the complexity of the design is reduced from (a) to (d). The overall form of the product is the same, but the number of parts and steps required to assemble them has been reduced.
DfD
Design for Disassembly
Designing a product so that when it becomes obsolete it can easily and economically be taken apart, the components reused or repaired, and the materials repurposed or recycled.
A designer might consider:
How parts are assembled and disassembled
Designing modules that can be replaced easily when repair is needed
Including information on the product about the materials to aid recycling
How the parts can be refurbished, reused, and resold
Adapting designs for Design for Manufacturing (DfM)
Reduce the total number of parts: Adapting a design so that it uses a fewer number of parts will reduce costs in a number of areas:
reduced inventory
handling
Reduced development and engineering time
Develop a modular design: Modular designs allow for easier repair and replacement, as well as fewer overall parts.
testing and quality control can be simplified
repair, servicing, and replacement is simpler
Use of standard components: Standardized components reduce the complexity of the design and save engineering and development
lower inventory costs
no need to develop, engineer, and prototype the part.
Design parts to be multi-functional: Developing parts that can serve multiple functions will simplify the design and reduce the number of parts and associated production costs.
Design parts to have multiple functions where practical. For example, a motor housing that also serves as a base for the product
Design parts for multi-use: Designing parts that can be used across a range of products will reduce product development costs and simplify inventory, repair, and replacement.
Design for ease of fabrication: Designing products that can be assembled in minimal steps, using minimal machines or tools, and in a logical order
Designing to be assembled from bottom up
Avoid separate fasteners: Separate fasteners add to the production time, machine needs, and inventory costs
Replace screws and nuts and bolts with snap-fit or adhesives where practical
Minimize assembly directions: Simplified and logical assembly procedures will reduce human error and increase productivity.
Minimize handling: Reducing the number and length of time a product or part needs to be handled, transported, or moved can reduce production time and costs