BimScaler Blog – DFA, or Design for Assembly, is a set of principles that aim to streamline manufacturing processes by making assembly easier and more efficient. Implementing DFA principles can help manufacturers reduce costs, improve quality, and increase productivity.
Simplifying part designs, minimising the number of parts needed, and ensuring ease of assembly are the key principles of the DFA process. Implementing DFA involves careful planning and consideration of how components will come together during the manufacturing process.
Let’s keep reading to learn more about the DFA method, including its definition, principle, and how it differs from design for manufacturing.
Design for Assembly, abbreviated “DFA,” is a process of designing products and assemblies to make them easy and efficient to assemble. The goal of DFA is to minimize the number of parts, reduce the time required for assembly, and lower the cost of assembly.
This approach is essential for manufacturability and helps decrease production time, production cost, material usage, and waste. It also increases product reliability and ease of assembly and disassembly, which are essential for repair and maintenance.
In the Design for Assembly process, three questions are asked to determine which part will be put into the assembly:
- Does the part have to move relative to other parts in the assembly?
- Is the part made of a different material for aesthetic or functional reasons?
- Does the part have to be separate to guarantee access to other parts or to be able to carry out repair and maintenance?
Answering these questions can help designers optimize the assembly process by ensuring that parts are designed in a way that minimises complexity and maximises efficiency. This ultimately leads to a more cost-effective and reliable final product.
Before we go deeper about DFA, you might want to explore another design discipline, civil engineering design.
Before we get into DFA, you might want to check out another design discipline, civil engineering design.This design discipline is the process of creating plans and specifications for the construction of infrastructure projects, such as buildings, roads, bridges, and other structures.
Find out more about it in our post, ‘Civil Engineering Design: Definitions, Process, and Types‘.
Principles of Design for Assembly
There are 7 main principles of DFA, which are: minimising part count, modularity, built-in fasteners, part symmetry, mistake-proofing, use of standard parts, and use of reasonable tolerances.
The Fractory blog explains in detail how each principle can improve the customer experience and create an efficient assembly design.
- Minimising part count: Higher design quality is indicated by fewer parts, which facilitates assembly, repair, and manufacturing. For implementation to be as economical as possible, designers and other departments must communicate effectively.
- Modular design: Incorporating modular assemblies saves time, especially for similar products, while also improving repairability and customisation, thereby extending product utility and lifespan.
- Built-in fasteners: Consider eliminating or minimising traditional fasteners like screws and bolts in favour of built-in options such as snap fits and adhesive fasteners, which simplify assembly without requiring special equipment. Strive for common parts and tools across the product line to streamline assembly processes.
- **Part Symmetry:**Symmetrical designs streamline assembly by reducing reorientation time. Components should fit interchangeably to eliminate confusion among assembly workers, while deliberate asymmetry helps prevent orientation errors.
- Mistake-proofing (Poka-Yoke): Physical obstructions should be used to prevent incorrect assembly, with simple notches or features assisting in identification and ensuring correct assembly.
- Use commercially available standardised parts: Opt for commercial off-the-shelf (COTS) products to minimise custom machining and fabrication, including items such as motors, gears, springs, and enclosures. This approach accelerates both the manufacturing and product design processes.
- Keep tolerances realistic: Avoid excessively tight tolerances to mitigate production costs and potential assembly issues, recognising that precision machining can significantly increase time and expenses.
Tools and Software for DFA
DFA can be facilitated using a variety of software tools and design guidelines. Some common ones are listed below.
Computer-Aided Design (CAD) software
CAD software is essential for creating and modifying the geometry of parts.
It allows designers to check for interferences, clearances, and tolerances and can also be integrated with finite element analysis (FEA) and computational fluid dynamics (CFD) modules for structural, thermal, fluid, and dynamic behaviour evaluation.
Examples of CAD software include SolidWorks, Autodesk Inventor, Fusion 360, and Creo.
Design for Manufacturing and Assembly (DFM/DFA) software
DFM/DFA software is a specialised tool that analyses CAD models and provides feedback on how to reduce the number of parts, standardise parts, minimise assembly time and cost, simplify assembly sequence and orientation, eliminate or reduce fasteners, and improve ergonomics and safety.
Examples of DFM/DFA software include Boothroyd Dewhurst DFA, Geometric DFMPro, and Siemens NX DFM.
Assembly simulation software
Assembly simulation software creates realistic and interactive animations of the assembly process, verifying the assembly operations, tools, fixtures, and human or robotic actions involved.
It can also check for errors, collisions, and the feasibility of the assembly process, as well as estimate assembly time, cost, and quality. Examples of assembly simulation software include Delmia, Process Simulate, Robcad, and Visual Components.
Virtual reality (VR) software
VR software allows users to immerse themselves in a simulated environment and interact with product designs and assembly processes.
It can help evaluate ergonomics, usability, functionality, and aesthetics and test different scenarios, variations, and alternatives. Examples of VR software include Unity, Unreal Engine, Vuforia, and Sketchfab.
Optimisation software
Optimisation software uses mathematical models and algorithms to analyse data and parameters, generating optimal or near-optimal results that meet objectives and constraints.
It can help optimize the shape, size, weight, material, cost, performance, reliability, and quality of product components and assemblies. Examples of optimisation software include MATLAB, OptiStruct, ModeFrontier, and Lingo.
Design guidelines and checklists
Design guidelines and checklists can help optimize manufacturing and assembly by considering factors such as tolerances, dimensions, surface finish, machining requirements, assembly sequence, assembly tools, and assembly time for each component. These tools can help identify and eliminate potential problems or inefficiencies in the design.
What is the Difference Between DFM and DFMA?
Design for Manufacturing (DFM) and Design for Manufacturing and Assembly (DFMA) are related concepts, but they differ in scope and focus.
DFM primarily focuses on optimising the manufacturing process by simplifying part designs, selecting appropriate materials, and minimising manufacturing costs.
On the other hand, DFMA extends the scope to include assembly considerations, emphasising the integration of both manufacturing and assembly optimisations into the product design.
While DFM aims to reduce manufacturing costs, DFMA aims to optimize both manufacturing and assembly processes to achieve overall cost-effectiveness.
This is all you need to know about DFA. Aside from DFA, you might want to look into mechanical design.
Mechanical design is the process of generating detailed plans and drawings for mechanical systems or components. Read our post, ‘Mechanical Design: Definition, Process, and Types of It‘, to learn more.
Conclusion
Design for Assembly is a powerful methodology that is essential to lowering production costs and improving manufacturing efficiency. Adopting DFA is becoming more and more essential for manufacturing companies to remain competitive in the global market as they continue to change.
In the context of construction projects, combining DFA principles with BIM technology can help construction companies achieve greater efficiency, reduce waste, and improve collaboration among different stakeholders. That is why, in addition to the DFA principle, incorporating the BIM process is an important component of a company’s efficient construction project.
So, are you ready to implement the BIM process for your construction project?
BIMscaler’s consulting and management services will provide you with end-to-end BIM usage for your project, starting with BIM/model management, content management, project start-up, project meetings, and end-user support, including as-built documentation creation.
As a leading Australian provider of BIM services, BIM Scaler assures you of a professional and effective BIM implementation for your building project.
