What are the most important mechanical design considerations for easy assembly and disassembly?

Minimizing parts is a significant consideration for easy assembly and disassembly. This reduces errors and simplifies the process. Additionally, Design for Manufacturing (DFM) is crucial even with fewer parts, ensuring better manufacturability. In summary, keeping the number of parts to a minimum while optimizing their manufacturability is key for easy assembly and disassembly.

An example of designing assemblies to reduce assembly time is by reducing the number of fasteners or different tools needed to assemble the components. Reducing the number of fasteners or eliminating hardware by using alternatives like rivets and clips can reduce assembly time while maintaining strong connections. Using the same hardware in multiple spots can eliminate tool changes.

Mechanical Design consists of 3 phases: 1. Conceptual Design 2. Embodiment Design 3. Detail Design Once you have finalized a concept for your design, you need to decide as an engineer how to bring this concept to life in the most convenient and efficient way possible. In my opinion, the following steps are crucial 1. Planning the product architecture is crucial. Modular Architecture with standard components provides the maximum ease in Assembly. 2. Consider the manufacturing processes involved, the geometric dimensions and tolerances and Assembly components required 3. Develop drawings with appropriate GD&T for the type of fit. Incorporate DFM and DFA. Calculate and select the assembly components. 4. Consider Ergonomics in Assembly

Every assemblies are made for the purpose of performance. Design can not compromise them for ease in assembly or disassembly. Tolerance and fits are the best parameters to be considered for ease. Balancing efficiency, performance, life, ease in repairs, repairability, reliability after reassemblies are the factors to be considered first. Reducing components is a good idea but should not cost the performance and reliability. With best tolerances and fits if you achieve 95% efficiency and with little open tolerance if you achieve 92% efficiency and life, why should you spend more. One can use equation, Eff 1 * LCC (Life cycle cost) 1 = Eff 2 * LCC (Life cycle cost) 2. Above equation answers all aspects of a good design.

When it comes to design, there are two primary considerations: functional requirements and assembly requirements. While many argue in favor of beginning with functional requirements, my approach prioritizes assembly requirements slightly ahead of functional ones. The rationale behind this is that if we cannot efficiently assemble a product, its functionality becomes irrelevant. Since the design will ultimately be produced on an assembly line, the time and effort needed for assembly have a direct impact on cost. Therefore, it is crucial to streamline the assembly process to minimize both time and effort.

The other school of thought is to design your parts so they only fit together correctly. This way it is not possible to incorrectly assemble parts. An example is using different bore sizes for a flexible and rigid side of a shaft coupling.

In my point of view as a construction lead, make it simple and efficient. This way will allow disassemble / modification if necessary.

Modular design and Integral design are the two strategies for design . When the functional elements of an assembly dont require to assembled and disassembled in service then integral design can be used considering the design for manufacturing and assembly aspects. But when flexibility and replacement is required modular design is better. There is always a trade off and reasoning for each unique situation on which approach to use.

If you work for a comp/corp its important to use parts within corp because the hard work of numerical analysis and DFM is done. You can save costs throughout the project.

Yeah the one mentioned would eliminate most of the assembly and disassembly problems. But, what if the design is made in such a way that the assembly requires less human interference and more of a already assembled part and the disassembly would be easy and less of a human error. so when assembled correctly the component is joined and can be disassembled only at certain specific design areas.

Snapfits and press fits are great for low duty applications when the operating forces and moments are much lower than the forces required for separation of joint . High loads require bonding and fastening . Before deciding on fastening methods its important to do a simple static force analysis to know the range of forces and moments generated.

Make it so the assembly or the disassembly is used by few tools. Design it so the nuts and bolts or screws use the same size or few sizes for minimal need for different tool sizes.

Nothing's more frustrating than equipment with a mix of fastener types and a mix of SAE and metric standards. Thoughtful designs minimize the variety of fasteners and tools required. Special tools should absolutely be avoided, but if not possible then including them with the equipment should be considered (i.e. the fuse removal tool included in the fuse box of a car).

Single sided fasteners, where access is restricted. Commonality of fasteners. For example if using M6 socket head cap screws, try to minimise the number of lengths to avoid confusion. Rather than using M6x10, M6x12, M6x20, etc. I disagree that screws are complex! Snap fits and press fit parts can be prone to damage when disassembling.

Before considering fastening, know the forces and moments acting on the joint, and what is required to install and maintain the product. Vacuum is usually forgotten, as it can also be used for connecting airtight materials temporarily, such as in glass suction mounts, or in material handling.

DFA works on simplifying the manufacturing and maintenance processes by reducing the number of parts, optimising component shapes, and decrease the need for custom tools.

Design for Assembly (DFA) can be used to overcoming the challenges associated with mating intricate and inadequately complex parts. However, it is important to acknowledge that this design methodology requires additional effort in tolerance design. For instance, opting for fit tolerance instead of interference tolerance can prove effective, particularly in applications that are not subjected to high levels of vibration or dynamic loads. Incorporating geometrical tolerance based on the standards outlined in the ASME code becomes imperative when preparing shop drawings for such designs. By adhering to these guidelines, manufacturers can ensure accurate and precise assembly, facilitating the successful realization of the intended design.

One very useful principle which I have found impactful in design is Exact constraint design . Making the design in such a way that the degrees of freedom of the joining components get constrained automatically through the process of assembly just enough for function but not more making it redundant . Using 10 bolts to joining one plate to another when only 3 can suffice is one way of thinking about it.

Error proofing. For sure symmetric parts are great for ease of design but if a part can only be installed in one orientation then it makes assembly/re-assembly far less prone to error.

Incorporating Design for Assembly (DFA) principles is key for easy assembly and disassembly. DFA focuses on simplifying the manufacturing and maintenance processes by minimizing the number of parts, optimizing component shapes, and reducing the need for custom tools. By adhering to DFA principles, you streamline assembly and disassembly, decrease production costs, and enhance overall efficiency and user-friendliness.

Incorporating Design for Disassembly (DFD) principles has a significant impact on mechanical design considerations for easy assembly and disassembly. DFD focuses on designing products with end-of-life recycling or reuse in mind. This reduces waste and environmental impact. By considering DFD, products become more sustainable, and disassembly becomes more straightforward, facilitating the recycling process and contributing to a more eco-friendly approach to design and manufacturing.

Generic Requirement: Question the requirements along the PLC development: still designing in the right direction? Meaning, is the current design status still verifiable and valid with respect to the requirements? Is there any advantage to gain through modification of one or more requirements? Specific Requirement: Manual Handling/Tooling Required space/volume, a technical derived requirement, in order to satisfy the necessity of accessibility for assemblage and installation, and vis versa.

when assembling a product it is important to be mindful the client might need to disassemble for x reason (s). So you should make it logical process of disassembly, not easy mind you! That might take a few versions after the prototype phase. Try not to use welds and rivets but this is not possible all the time.

DFD is great. One big one here would be to avoid adhesives if you can but should really be dependent on how often that component should even be serviced. More and more manufacturers are aiming to reduce cost by making things less able to be serviced. In some cases, those items simply shouldn't be serviced and so putting effort into that may not be beneficial to the end user or the manufacturer. The use of sealing gasket, o-rings, seals in most cases is preferred but adhesives definitely have a time and place where many reusable sealing materials cannot perform the same way.

DFD principles not only improves OEE but also an important principle in designing products from cradle to grave. The designer must consider how the product will be disposed at the end of it's life.

Design assembly procedure to be foolproof so that even if the assembler didn't read the instructions carefully the assembly will not be achieved without exposing either the assembler, operator, or the machine to danger.

Utilize “poke yoke” or mistake proofing in your design. This means design your assembly so that parts cannot be assembled wrong. A common poke yoke is designing the part to fit only one way by mechanically blocking the other orientations. A good part only goes on one way: the right way.

Like we know, making a prototype a much easier to proceed the mass production manufacturing. It also means you need to consider all the human factors inside your product design, tooling design, and process design. The best mechanical engineer is to design a product which can let anyone to produce every product with same quality level through your drawings and procedures.

The design must be flexible enough to include human errors. Also, human safety must be considered while assembling or disassembling either on the machine or by hand. It should be accessible, intuitive, and yes not too convoluted.

Proper fixturing of assembly parts or designing the parts not to need a fixture for assembly aids the assembly operator by providing a solid base to work off. Additionally, assembly parts should be easily accessible from a seated or standing location for as many assembly operators as possible.

Key Design Techniques for Optimal Assembly Efficiency Poka-yoke: Prevent Misalignment Poka-yoke techniques ensure accurate assembly orientation, averting potential operational mishaps. It's about saving time, costs, and ensuring safety during product use. Location Duplication: A Silent Culprit Overlooking duplicated feature locations can lead to functionality failures. This often unnoticed issue can impact assembly integrity significantly. Harnessing Circular Features: Design Control Powerhouse Circular shapes offer simplified design control, limiting movement and enhancing precision. They're a mechanical design boon, reducing complexities in assembly.

Use Appropriate GD & T During Part Design make easy manufacturing and easy assembly if you don't do this so many problems occur in the process that's why in the design field use experience guys.

Usage of error-proofing, incorporating Poka Yoka principles to make sure it is impossible to assemble the part in the wrong way is must and also creates a good environment for the worker.

Tolerance stack-up and jigs! Proper understanding of your tolerances in each individual component, and how they stack up when going to assembly is crucial so you don't find yourself with misaligned holes for example:) Further, the use/design of jigs for the assembly process is a great ally! How to make sure your components are properly aligned? How can you help the operator do the job efficiently?

Access for commonly available commercial tooling. Assume the maintenance engineer will need to use a standard combination spanner and allen key/torx bit. Model them up in 3D and make sure you have access to get them into the area and can turn one fastener whilst holding the nut or vice versa!