A major problem in production manufacturing is converting consumers’ needs into final designs. Due to this, advancement in the production process became a necessity, leading to what is now called design for assembly (DFA). Design for assembly is vital in ensuring that manufacturers are relevant and well-equipped to fulfill customers’ expectations. This article will explain design for assembly in detail, its principles, and its importance in product development. Let’s get right into it!
What is Design for Assembly?
Design for Assembly (DFA) is a process that centers on the ease of assembling a product by decreasing the number of parts. It aims to reduce production costs and minimize the number of assembly operations. Fewer parts in a product make it easy and fast to assemble, reducing the cost of assembly.
Therefore, DFA is a cost-saving tool that helps design teams to enhance product designs even before manufacture, as they focus more on its functionality and ease of assembly.
Why is DFA Important in Product Development?
Design for assembly is becoming an essential part of product development due to the following reasons:
Adherence to design for assembly principles aids in identifying potential design issues in the early stages of the production cycle, driving down production expenses. This is very important for example in sheet metal production where it helps reduce sheet metal count and the number of processes needed to produce the sheet metal parts. Consequently, there are lower production costs.
Faster Time to Market
Design for assembly optimizes design which eliminates multiple design changes and leads to quicker production. It ensures that new products are manufactured rapidly and get to the market faster.
DFA decreases the number of processes required to produce a part, minimizing the opportunities to fail in the entire assembly operation. This simplifies the product and leads to improvement in designs quality and reliability. It is also an important part of prototype manufacturing which requires speed and quality control.
DFA Principles in Product Design and Manufacturing
Applying DFA techniques ensures the optimum performance of parts, streamlines the assembly process and eliminates wastage during production. Here are some DFA principles in product design and manufacturing used by rapid prototyping companies:
Decrease Parts Amount
An essential rule in design for assembly is to combine parts whenever possible, as long as the viability of the part remains unaffected. This practice will simplify product design, reduce labor costs, and minimize errors.
Customers are interested in the functionality and quality of the product and not the internal structure or number of parts in the final design. So, try to create your product with the minimum number of parts possible.
Decreasing parts amount does not translate to eliminating features. Instead, parts are thoroughly inspected to see how they can be merged for a simplified final product. Combining adjacent, similar and symmetrical parts when possible will reduce complexity and decrease the number of parts.
Optimizing Tolerance Requirements
Most times, people think that strict parts tolerance improves product quality. However, such strict tolerance requirements will raise manufacturing costs, leading to a longer production cycle, incurring more costs, and increasing the risk of performance issues.
The higher the part tolerance requirement, the higher the part costs. Therefore, loosening tolerance requirements for assembly-oriented product design cuts costs and enhances the resilience of designs.
Using Same Fasteners Across Assembly
Fasteners do not have added function or quality to the part, and the development process is labor and cost-intensive. Therefore, the use of fasteners should be reduced in product design.
If there are various types of fasteners, consider using the same style across the assembly. This practice will reduce the hassle of controlling multiple types of fasteners, decrease the types of auxiliary tools on the assembly line, reduce cost and prevent assembly errors.
It is good practice to use one type of fastener, as using too many types can lead to operation errors with the wrong kind.
Build Fasteners into Part Design
Incorporating fasteners into parts in place of bolts, screws, and other components is another way to decrease part count and optimize product design. As screws require more time and effort to assemble, fasteners like snaps and tabs do not need special equipment to simplify the assembling process. Screw and nuts should be eliminated unless the assembly requirements are high for that part.
Reduce Parts Assembly Orientation, Easy to Orient
The assembly orientation of parts should be simplified and be as few as possible for product assembly. Having too many orientations can cause the parts to shift, rotate or flip during the assembly process, which will lead to the inefficiency of parts and make the operator fatigued. For example, rapid prototyping companies’ product design should be structured such that the assembly orientation of parts is from top to bottom, as this is the ideal direction. On the other hand, the bottom-up direction is labor-intensive and time-consuming, as the gravity of the product needs to be overcome, and it causes quality problems.
Always remember, the simpler the design, the easier it is to assemble. Therefore, consider the tools and equipment for the assembly and incorporate enough operating space for ease.
Simplify the design and design features that aid the easy assembly of parts and cause minimal errors. To do this, minimize steps, ensure there are no obstructions or interference in the assembly process. Also, incorporate simple movement patterns for a smooth, efficient, and fast assembly.
Avoid Harm to Operator/Consumers
The safety of operators and consumers must always be prioritized during product assembly. Error in product design can cause harm to both operators and users. Therefore, special attention has to be placed on sharp edges and corners, as they can cause personal injury.
For instance, the sharp edges and corners in sheet metal chassis can easily scratch the fingers. In this case, the flashing process has to be incorporated into the design to improve the safety of operators or consumers. Therefore, the sharp edges and corners have to be fillet when designing the products.
The practical application of design for assembly principles is pivotal in product design and production. Therefore, following these principles will improve the quality and reliability of products especially by rapid prototyping companies. This article provided you knowledge on DFA, its importance, and the principles to adhere to during product design and manufacturing.