Machine designing:- Part1

The basic procedure for the machine design is a simple and straightforward step to step approach from the functional requirement to the creation of drawings of the final product.

Following is the scenario in the designing.

·        Begin with the market survey.

·        Go with the in-detail market study and find out exact need.

·        Define the detail specification of the product. Here make the detail list of the product specifications. Define the cost of each one.

·        Find out the alternative mechanism for the product.

·        Select the mechanism which will suit the product. Here it can be crank and connecting rod or other which will give the best result. This mechanism should be fitted in the desired cost of the product.

·        Prepare the detail layout. Here define each component with its details.

·        Define the assembly methods of the components and the process.

·        Design all the individual components. Here total force required should be calculated. Also, material selection plays a vital role in this process. Along with it, the modes of failure should be determined in the detail and it should be discussed with the DFMEA.

·        Prepare assembly drawings. Here use the various design tools.

·        Modify the drawing and finalize them before the implementation of the product.

While designing any component the following points should be noted carefully.

·      Strength: - The machine or the product should not fail or stop due to accident or the external forces acting on it. It should have enough strength to withstand all the forces acting on it.

·       Rigidity: - The product or machine should be well rigid enough. It should not bend or deflect at any cost.

·      Wear Resistance: - It is the main reason for the machine breakdown. It reduces the life of the component.

·      Lesser dimension and the weight: - The machine should be strong, rigid and the same time, it should have minimum dimensions and the weight. This helps to reduce the cost of the machine.

·  Manufacturing ability: - Designed part of the component should be easy for manufacturing with the minimum cost.

·    Safety: - The shape and the dimensions of the part and component should provide the safety for the operator of the part or component.

·  Conformance to the standards: - The designed part should be according to international standards.

·        Reliability: - The machine should be reliable for an extended period of time.

Design of the machine elements is an important part of the complete designing procedure. Following are the steps in the machine designing.

·        Define the functions of the element.

·        Find out the forces acting on it.

·        Select a suitable material.

·        Find out the potential failure modes of the material.

·        Determine the dimensions of the component.

·        Check the dimensions for the assembly.

·        Prepare working drawing

Following are the functions of some of the machine elements

Bearing: - It supports the rotating shaft.

Key: -It transmits the torque between the shaft.

Spring: - It stores and releases energy.

Screw fastening: - It holds two-three machine parts together.

While determining the force, draw the free-body diagram to determine the forces acting.

To be continued….

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Kaushik