Advanced Sheet Metal Design Using NX Cad Challenge_7_ Metal bracket-II

PROJECT REPORT

TITLE: DESIGN OF SHEET METAL BRACKET II IN NX CAD

OBJECTIVE: To design and model the sheet metal bracket II from a 2D Sketch in sheet metal workbench of NX CAD version 11.

INTRODUCTION: NX is a 3D CAD CAM software developed by Siemens. The Casing will be designed and modelled in the sheet metal workbench of the NX.

Sheet Metal is a metal formed by an industrial process into thin, flat pieces. It is one of the fundamental forms used in metal working and it can be bent into variety of shapes. Countless everyday objects are fabricated from sheet metal. The thickness can vary significantly, extremely thin sheets are called foils and sheets having thickness greater than 6mm are called plates.

DESIGN METHODOLOGY:

DESCRIPTION:

The tools and features used in the design and modelling of the enclosure are:

Sketching:

A profile of the required shape of the metal bracket in the YZ plane is created.

Fig 1. Sketching

Contour Flange:

A profile for the contour flange is created. Using the command contour flange the 2D Sketch can be converted into a 3D flange.

Fig 2. Contour Flange

Normal Cut Out:

It is the type of cut out which is mainly preferred in sheet metal design. The advantage this type of cut out has over the extrude cut out is that normal cut out removes the material perpendicular to the surface of our model rather than plane.

First the sketch is generated. The Sketch has already been created in the YZ plane and using the normal cut out the material is removed from the part.

Fig 3. Normal Cut Out

Fig 4. Normal Cut Out

Fig 5. Normal Cut Out

Fig 6. Normal Cut Out

Break Corners:

It is to give smooth finish to the sharp corners. The radius parameters are given in the break corners command and the corners will be smoothened.

Fig 7. Break Corners

Fig 8. Break Corners

Fig 9. Break Corners

Fig 10. Break Corners

Fig 11. Break Corners

Unbend:

The part is unbend to create additional features such as hole, dimple, beads which otherwise cannot be created if it not unbend. Moreover it also helps to check whether the part is a sheet metal or not. If the part is unbending then it is a sheet metal otherwise it is still a solid body or dumb body.

Fig 12. Unbend

Normal Cut Out:

A profile for the normal cut out is created. Using the command normal cut out command the material is removed.

Fig 13. Normal Cut Out

Rebend:

After creation of additional features the part is rebend back to get our required product.

Fig 14. Rebend

Advanced Flange:

Advanced Flanges are the flanges which can be created on the non linear or tangent curves. The advanced Flange command is available in the sheet metal workbench of NX. The tangent curves option is selected and the flanges are created on these edges.

Fig 15. Advanced Flange

Unbend:

The model is unbend again to create additional feature of holes.

Fig 16. Unbend

Holes:

The additional features holes are also created. Hole command is available in the sheet metal workbench of the NX CAD. The points where the holes are required are specified.

Fig 17. Holes

Normal Cut Out:

The profile for the normal cut out is generated and by using the command the material is removed to get the desired product.

Fig 18. Normal Cut Out

Fig 19. Normal Cut Out

Advanced Flange:

The newly created hole is given flange by using the advanced Flange command.

Fig 20. Advanced Flange

Rebend:

After the creation of the additional features the model is rebend back to the original shape.

Fig 21. Rebend

Gussets:

Gussets are the strength stiffening features. They add strength and stiffness to the sheet metal parts. The face and the plane is selected for the gussets to be created and the profile is generated. The profile can be automatically generated or the sketch can be created.

Fig 22. Gussets

Fig 23. Gussets

Fig 24. Gussets

Fig 25. Gussets

Flat Pattern View :

It is the last step of the sheet metal design. The created model is flattened out to know the exact length of the blank required for its manufacturability. By selecting the flat pattern the view of flat pattern is created and this view is added in the drawing sheet.

Fig 26. Flat Pattern

THE MODEL VIEWS:

Fig 27. Top View

Fig 28. Right Side View

Fig 29. Left Side View

Fig 30. Bottom View

Fig 31. Front View

Fig 32. Isometric View

DETAILED DRAWING SHEET:

Fig 33. Detailed Drawing Sheet

CONCLUSION:

1. This project helped me to understand how to convert a 2d Sketch into a 3D sketch.
2. Got a good understanding of features like gussets, holes, and advanced flanges.
3. The creation of flat pattern view, bend table and the addition of flat pattern view in drawing sheet.

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