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

METAL BRACKET-II

OBJECTIVE

The main importance of this project is to model a sheet metal bracket with some advanced features of sheet metal operation like advance flange, gussets to provide the bracket with stiffenning features.

INTRODUCTION

In this project we are going to learn about the different manufacturing processes that can be performed on a sheet metal. There is a factor known as the "K" factor which aids us in giving appropriate bend radius to the available sheet metal thickness. The K-factor comes from the ratio of the neutral radius divided by the thickness of the material on prepared charts and has a value between 0.3 and 0.5.

Sheet metal is metal formed by an industrial process into thin, flat pieces. Sheet metal is one of the fundamental forms used in metalworking, and it can be cut and bent into a variety of shapes. Countless everyday objects are fabricated from sheet metal. Thicknesses can vary significantly; extremely thin sheets are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate steel or "structural steel".

DESIGN METHODOLOGY

The sheet metal preferences are set before the creation of a 3D element. The most important method we follow for the design of any sheet metal component is that, if we want to create holes, dimples, beads and normal cutouts, we need to first unbent the whole sheet metal model and make it a flat sheet and then do the required features and after all features are created the model is rebented to get its final design. This is done for ease of designing and to get a properly positioned features.

DESCRIPTION

• Sketch

A sketch is first created on the YZ-plane and then on the XZ-plane so that a contour flange can be created and cut out the unwanted material.

• Contour Flange

It is created by extending the sketch on the XZ-plane with thickness as required from the base. Here the thickness given is 3 mm and width is 158 mm.

• Normal Cutout

It extracts material volume from sheet metal by using sheet metal production principles. Cutting faces will be perpendicular to the sheet metal surface.

• Unbend

One or more curved surface such as bends or curved walls to a flat configuration in a sheet metal part. For performing a unbent feature, it must define a fixed planar face or edge. We can select the curved surface of the bend as the input parameter.

• Break Corner

It is used to round the sharp edges with user specific radius. The input parameters are the faces which connects the edges.

• Rebend

This coommand is used to rebend the unbent sheet metal along with the features applied sfter the unbent. After addition sketches and features the sheet metal is to be rebented to its required shape. This operation is done by box selecting all the features and clicking the rebend command.

• Advanced Flange

This command is a very powerful tool because it can easily form flamges in a tangent curves or in complex shapes of the feature

• Hole

General holes are created with the sketched points with a diameter of 6 mm. This tool created a counter bored, counter sink and several hole options.

• Gusset

Sheet metal gusset tool can quickly add various size and shaped gussets to the bend parts which will provide additional strength to the model.

• Flat Pattern

Flat pattern is the representation of the entire sheet metal component in the 2D form with all the bends, cutouts, holes and additional features in the form of lines or edges. The flat pattern ensures the ability to cut the sheet metal out of the raw sheet metal plate. It removes the possibility errors such as interference or collision within the same component.

STANDARS VIEWS

• Front View

• Side View (Left)

• Top View

• Isometric View

DRAWING SHEET IMAGES

After designing 3D model for further process of manufacturing we have to convert the entire sheet metal component into 2D form for easy interpretation. For this project of add shaped enclosure design a drawing is created out of the flat pattern in 2:1 scale in A4 size sheet.

• Flat Pattern

• Standard Views

CONCLUSION

By using the proper design methodology and advanced sheet metal tools the sheet metal bracket design has been compleated using the Siemens NX software.