Tech Mahindra Mechanical Engg. Design Interview Questions, Process, and Tips

Sheet metal fabrication processes involve various techniques to shape and form sheet metal into desired products.

• Cutting: Techniques like shearing, laser cutting, and waterjet cutting are used to cut sheet metal into desired shapes.

• Bending: Sheet metal is bent using techniques like press brake bending or roll forming to create angles and curves.

• Forming: Processes like deep drawing, hydroforming, and stamping are used t...read more

Draw shear and bending moment diagrams for a cantilever beam.

• Calculate reactions at the support

• Determine the equation of the shear force diagram

• Determine the equation of the bending moment diagram

• Plot the diagrams using the equations

• Check for accuracy and consistency

Bending allowances are given to compensate for material stretching during bending process.

• Bending allowances are added to the flat pattern of a sheet metal part before bending.

• The amount of bending allowance depends on the material type, thickness, bend radius, and angle.

• Bending allowances are typically specified in a table or chart provided by the manufacturer.

• The bending allowance formula is: BA = (π/180) x R x (180 ...read more

The thickness used to manufacture in the mechanical engineering design industry varies depending on the specific application and materials involved.

• The thickness of components can range from very thin, such as sheet metal with thicknesses measured in millimeters, to thick structures like heavy machinery components with thicknesses measured in centimeters or even meters.

• The choice of thickness is determined by factors s...read more

Geometric Dimensioning and Tolerancing (GD&T) diagram for a rectangular box.

• Use basic GD&T symbols such as perpendicularity, flatness, and parallelism to specify the dimensions and tolerances of the box.

• Include datum features to establish a reference frame for the measurements.

• Consider the functional requirements of the box, such as its ability to stack or fit with other components.

• Use profile tolerance to control the ...read more

There are 14 symbols in GD&T (Geometric Dimensioning and Tolerancing).

• GD&T uses symbols to communicate design requirements and tolerances.

• These symbols are used to specify the shape, size, and orientation of features on a part.

• Some common symbols in GD&T include concentricity, perpendicularity, flatness, and position.

• Each symbol has a specific meaning and is used to ensure proper functionality and interchangeability of...read more

Flat process is preferred in sheet metal fabrication for ease of manufacturing and cost-effectiveness.

• Flat process involves cutting and bending sheet metal in a single plane, reducing the need for complex tooling and machinery.

• It also allows for easier handling and transportation of the sheet metal.

• Flat process is more cost-effective than other processes like deep drawing or hydroforming.

• Examples of products made using...read more

Flanges are selected based on factors like pressure rating, material compatibility, and application requirements.

• Flanges are selected based on the pressure rating required for the specific application.

• Material compatibility is crucial in selecting flanges to ensure they can withstand the intended environment.

• Application requirements such as temperature, fluid type, and pipe size also influence flange selection.

• Common t...read more

Tolerances are used in CAD drawings to ensure that the manufactured part meets the required specifications.

• Tolerances help to control the variation in dimensions and ensure that the parts fit together properly.

• They also help to reduce manufacturing costs by allowing for a range of acceptable dimensions rather than requiring every part to be made to exact specifications.

• Tolerances can be specified for various dimensions...read more

I am proficient in AutoCAD, SolidWorks, and CATIA with over 3 years of experience in each software.

• Proficient in AutoCAD, SolidWorks, and CATIA

• Over 3 years of experience in each software

• Able to create 2D and 3D models, assemblies, and drawings

• Familiar with GD&T and ANSI standards

• Experience in designing mechanical components and systems

• Ability to work with large assemblies and complex geometries