Why you need Design for Manufacturing and Assembly (DFMA) and how to get it done
Design for Manufacturing and Assembly is a critical step in making your product cost-effective to produce
The process of product manufacturing and assembly is expensive. It costs manufacturers millions and, at times, billions of dollars. If the process is streamlined, it can save manufacturers significant cost and contribute to an efficient assembly line and reduced manufacturing period. So, applying a single methodology can make multiple manufacturing domains economic and efficient at the same time. The process is called DFMA.
What is DFMA?
Disclaimer: This is only going to get a bit complex. Proceed with attention to detail.
DFMA stands for Design for Manufacturing and Assembly. The terminology encompasses the separate domains of:
- Design for Manufacturing (DFM).
- Design for Assembly (DFA).
The purpose of DFMA
DFMA is the use of standard concurrent engineering studies or a set of defined guidelines aimed to ensure that a part, assembly or process is designed in such a way that it makes the whole process economical, and reduces development and manufacturing cost. It also decreases the number of steps and time involved for the development and assembly of the product, and optimizes the whole manufacturing cycle.
The process of DFMA greatly helps in identifying and quantifying improvements and assessment of cost. It can help eliminate inefficient steps or procedures in the product design, and contribute towards lean manufacturing. DFMA serves as a reference tool to study competitors' products, and also serves as a cost analysis tool to assist in negotiating with the suppliers.
Components of DFMA
As stated above, the process of DFMA is an amalgamation of two separate industrial domains. We will be discussing each individually:
Design for Manufacturing (DFM) is a process that focuses on the designing of manufacturing components, or producing parts of a product efficiently. The process emphasizes reducing the complexity of a part to improve the quality and reduce the cost of production of the component itself. We can summarize it all as the optimization of the process of manufacturing.
It's a tool used for the selection of the most cost-effective materials and products to be used in the early stages of product development and design.
Design for Assembly (DFA) is the process of designing products for ease of assembly. The process isn’t about just the design of the product, but also about the development of its subcomponents and subassemblies, the tooling involved and the assembly method. The emphasis is on the reduction of the number of steps involved in the assembly process.
It's a tool that helps engineers and design teams design optimized products, or ones that can further be optimized at a minimum cost. The emphasis is on the number of parts/components involved along with handling and ease of assembly.
What are the differences and similarities between DFM and DFA?
Seemingly similar, the processes of DFM and DFA are rather different as they each focus on a separate industrial domain. One has to be aware of industrial intricacies that separate the two domains in order to understand how they differ from each other.
- DFM is exclusively concerned with reducing overall part production costs. It is used to decrease the complexity involved in manufacturing operations.
- DFA is exclusively concerned with reducing product assembly costs. This includes minimizing the number of assembly operations.
On the other hand, the similarities between both procedures can cause some confusion as to how different the two domains are in the first place. Similarities include:
- Both the processes (DFA and DFM) are used to reduce material, labor and overhead costs involved in manufacturing a product.
- Both methods contribute to a reduced product development cycle.
- Both the procedures make use of defined industrial standards to contribute towards economical and efficient development of products and assembly.
Why is DFMA used?
The primary purpose of DFMA is to reduce the cost by making changes during the design phase of a product. This is to design a part, assembly or an entire process in such a way that makes the quality, delivery time and cost optimal for manufacturers.
DFMA ensures that the process between designing and production progresses smoothly. Another advantage is that in the early stages of product design, manufacturability is also taken into account.
How does DFMA work?
The first step is the design of a product, which is nowadays done with the help of CAD software. It makes more sense to pay detailed attention to the design phase as it's easier to change a CAD design than to change an entire assembly or a manufacturing plant that's all tooled up. After a concept is developed, the application of DFMA methodology starts right away.
The first step is the implementation of DFA methodology. The configuration of a component will be analyzed from the top-level in order to simplify the overall architecture of the component. Experimentation is performed in this step by combining different parts or leaving them out and experiment with them interchangeably.
Then, only after the successful completion of the previous step, the materials to be used for the manufacturing of the part/component/product are selected. The process is designed accordingly, and after all the necessary iterations have been taken, the final and most optimized concept can be selected. The next step is detailing and optimization of DFM for the components involved.
The general guidelines of DFMA
The use of DFMA varies from industry to industry, product to product, and application to application. Still, there's a defined set of guidelines that are common to all applications and provide the most optimized results. These are:
- One of the primary purposes of DFMA is to reduce the number of individual and different parts involved in the manufacturing of a product.
- To try to make use of standard available components instead of designing a new one every time when a new product is to be developed.
- To design parts and components that can be used for multiple applications and in multiple product lines.
- To design components that are easy and simple to produce.
- To reduce the number of flexible components involved in the manufacturing of a final product.
- To design components for a product that are multifunctional in nature.
- To design parts in a fashion that makes them unable to be assembled incorrectly.
- To maximize the symmetry of parts manufactured or to deliberately make them asymmetrical as per the requirement of the process.
- To minimize the use of fasteners (as they tend to come loose often and require constant checking).
- To ensure that all the parts involved can be assembled linearly (from a single direction). Preferably from top to bottom, vertically.
- To design parts in such a fashion that they align themselves for easy assembly.
- To design products that don’t require specialized packaging and fit in standard packaging available.
- To design a modular product for the feasibility of both the manufacturer and customer.
Benefits of DFMA
Using DFMA, a product can easily be developed with a minimum number of components and reduced overall cost (labor, manufacturing, etc.). Here are some of DFMA's major advantages:
- Using DFMA, manufacturers have reduced the number of parts to design, revise or document.
- Reduced BOM (Bill of Material) cost along with parts to receive, inspect, store or handle.
- Reduced energy consumption (contributes to cost reduction and making the process economical) and the amount of labor to build products.
- Enables a part to be manufactured fast and reduces time to market, thus the product gets into the hand of the customer quickly.
- Reduces the overall complexity involved in the process while raising the quality of the product simultaneously.
- Improves the product profit margin and helps in competing in the already saturated market.
DFMA serves as a quantitative method to assess the design of a product. It also serves as a communication tool between the design engineer and other departments, with a chance for other departments to offer their insights before the product is developed. Finally, since almost 70–75% of the product cost can be determined in the designing/engineering phase, it provides leverage to the manufacturers to cut their losses before committing to a design.