Advanced Sheet Metal Design Using NX Cad Challenge_2_Box Assembly

               Title (‘Designing a Sheet metal Box Assembly by using Siemens NX-Sheet Metal Application’)

Click to view Project                                                                     Shaik_Thasleem_Ansari

Objective:

The main objective of this project is to design a Sheet metal Box Assembly by using Siemens NX-CAD  3D software.

Introduction:

NX, formerly known as "Unigraphics", is an advanced high-end CAD/CAM/CAE, which has been owned since 2007 by Siemens PLM Software.[1][2] In 2000, Unigraphics purchased SDRC I-DEAS and began an effort to integrate aspects of both software packages into a single product which became Unigraphics NX or NX.

It is used, among other tasks, for:

Design (parametric and direct solid/surface modelling)

Engineering analysis (static; dynamic; electro-magnetic; thermal, using the finite element method; and fluid, using the finite volume method).

Manufacturing finished design by using included machining modules.

Design methodology:

The above shown flow chart explains about the design methodology of designed sheet metal casing. First we need to create a tab of required dimensions later we have to use some features like Flange, Break Corner, dimple, etc. to design a sheet metal casing.

Features used:

Sketch: This feature is used to draw line, circle, rectangle, etc.

Tab: it is to create sheet metal block of required thickness.

Flange: this feature is used to create extended edges with adjustable K-factor and bend radius.

Break corner: this feature is used to fillet the sheet metal edges.

Normal cutout: it is used to cut the sheet metal in required sketch.

Dimple: this feature is used to lift an area of model inside a sketch which simulates a stamping tool.

Unbend: this feature is used to unbend the sheet metal.

Rebend: this feature is used to reminds original form of the sheet metal.

Bead: lifts the material along the contour of the model which simulates the stamping tool.

DESIGN PROCESS:

Units:

This project has been done using Millimeters as the base unit.

Processes:

(1) Creation of tab sketch:

The sketch was created on the XY plane. The rectangle tool was used to make the sketch and proper dimensions were added to fully constrain it. In this Siemens NX software, the drawn sketch is automatically constrained, it makes different than other software’s.  This provided the base for the tab feature which formed the next process in this project.

Flange:

Extended edges are formed by using Flange feature of NX-CAD. Where we can adjust the K-Factor and bend radius of the model. Using proper edges as a reference, the corners of the bent faces were modified to include flanges. This was done using the Flange feature.

Closed corner:

Used to close the corners where the two adjacent flanges meet by extending bends and flanges. This feature is exclusively available with siemens NX-CAD.

Hem flange:

This is a subgroup of type of flange. In this flange is created on form of open and closed loops. This feature is used mainly to strengthen the edges of sheet metal.

Mirror body:

This feature is used to mirror the body, not only that we can mirror the feature of the model. In this this feature is used to get the symmetrical body which acts like an container to the whole box.

Normal Cutout:

A rectangular cutout was then created on one edge of the base feature by using the Normal Cutout feature.

(6) Break Corners

The sharp corners which remained after the creation of solid features were smoothed using the Break Corners feature which rounded the sharp edges according toa proper radius value.

(7) Unbend

For the creation of additional features like holes, the bent portions were straightened using the Unbend

feature which was done by the systematic selection of the bent corners.

(9) Adding a Dimple

A depression was created using the Dimple feature which utilized the proper sketch to produce the result. The sketch consisted of a Studio Spline which was rotated about the center to create the required shape.

(10) Adding Beads

Using a similar algorithm to that of a dimple, the Bead feature creates a proper modification using a circle as the base sketch. Four beads are created in total, with the first one being mirrored about the proper plane to create the remaining. Both the dimple and the bead are features under the Punch category in Sheet Metal and signifies a stamping process.

(11) Rebending:

The final process consisted of reverting the model back to its original configuration by modifying the unbent edges using the Rebend feature. The path followed while unbending was repeated in a similar manner while rebending to ensure proper result.

Views of Sheet-Metal Casing:

Front View:

Top View:

Isometric view:

Side view;

Conclusion:

Being a sheet metal box assembly , it has been used every feature of Sheet metal, A Sheet Metal Box assembly has been designed by using simple sheet metal features of siemens NX-CAD software.