Advanced Sheet Metal Design Using NX Cad Challenge_1_Casing Design

OBJECTIVE

Create a Sheet Metal Casing design using Siemens NX cad software and there by learn the Sheet Metal design process

INTRODUCTION

In manufacturing industry Sheet Metal is one of the most versatile one. The main compositions are steel, aluminum, brass, copper, tin, nickel, titanium and other precious metals .It ranges in thickness from wispy leaf through light foil to heavy plate. Sheet metal consists of variety of forms; plain flat sheets, embossed, etched, ribbed, corrugated and perforated. The usage of sheet metal expands across many different industries including Transportation, Aerospace, Appliance manufacturing, Consumer electronics, industrial furniture, Machinery and more

Sheet Metal components can have deceptively complex manufacturing processes and the design process itself can be similarly NX cad, Solid works etc. are used to design the complex the sheet metal components

Sheet metal design software considers the fabrication methods needed for manufacturing .As we create flanges and add bends, the sheet metal design software will accurately represent the flat pattern required. The flat pattern can be used to document and manufacture associatively as the design changes

DESIGN METHODOLOGY

The casing designed for this project consists of features like Normal Cut-outs, bens, flanges, holes, dimple and beads. Every feature is designed in an order following the industrial procedure to keep the design intent .The design methodology used for this project can be summarized as depicted in the flow chart below

COMMANDS USED

SKETCH

TAB

NORMAL CUT OUT

BEND

FLANGE

BREAKE CORNER

UNBEND

HOLE

DIMPLE

BEAD

REBEND

FLAT PATTERN

DRAFT

All the commands are explained with pictures in description

DESCRIPTION

• SKETCH

are the basic foundation of a design model .A base sketch is needed ton perform most of the operations in sheet metal designing including Tab , Dimple, Bead , Hole , Contour flange etc can be created using the various sketch tools provided top left corner of the interface

Rectangle of length 60mm and 50mm width

• TAB

Tabs are the basic feature in NX Sheet metal designing process. Tab command in NX extrude a sketch along a vector by a thickness value or by adding material to existing face and bend regions of a sheet metal part

Base feature of casing design (1mm)

3) Normal cut-out

This command extracts volumes from sheet metal by using sheet metal production principles. Cutting faces should be perpendicular to the sheet metal surface

Using cutout command a cutout is performed at one side of the Tab using a rectangle sketch of 40mm length and 5mm width

• BEND

Bend feature is added whenever a bend the design is required .It may be in any position position or at any angle .A sketch is required to create a bend , it can be either a straight line or a curve for this project of casing design , two symmetric straight lines with respect to x axis are drawn for the bending curve

Both sides of the tab are bended at a length of 10mm and 1mm of bend radius

• FLANGE

This command consists of a face and a bend connected to an existing face along a straight edge. To add a flange feature, we select one more edges, and specify the size and position of the material added

Four flanges are added, two towards the inside and the others towards outside with a length of 5mm

• Break the corner

Break corner command is used to round the sharp edges with user specified radius

• UNBEND

UNBEND Tool to unbend one or more curved surfaces as bends or curved walls to a flat configuration in as Sheet metal part. For performing a unbend feature its must to define a fixed planar face or edge .W e can either select bend geometry individually or automatically select all bend geometry

Unbend command by Box selecting all the bend geometry

• HOLE

Hole feature in sheet metal design workbench is just like in the model workbench. It can create either simple or counter bore or countersink or tapped holes. For this casing first the four points are sketched symmetric to the x axis in position and the hole feature is applied.

Screw clearance of M2 is created as shown in the diagram

• DIMPLE

To create a raised dimple feature in a sheet metal part .The dimples can be placed on any flat surface including flanges and will extend in the direction of the face .The dimple feature will be governed by the settings defined in the options form. Dimple also helps in the sheet metal part to increase the stiffness

• BEADS

These are the features added in the sheet metal components in order to increase the stiffness of the material .Beads require sketches to perform. It can be either a opened or closed profile .For this casing design project, four small beads are applied in the symmetric position as shown in the below figure

Two Beads are created using circled of Diameter 5mm and mirrored it to the opposite corners as in the figure

• REBEND :-This command is used to bend the un-bended parts along with the feature applied after the unbend .After addition sketches and features the sheet metal is to be re bended to its required shape. This operation is done by box selecting all the features and clicking the Re Bend command

Re bend feature is performed

• FLAT PATTERN

Flat pattern is the representation of the entire sheet metal component of the entire metal component in the 2 D form with all the bends ,cut-outs , 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 possible errors such as interference or collision within the same component

• DRAFT

After the modeling, the manufacturing of the component a technical 2 D drawing of the component with accurate dimensions or scales denoted. For achieving this we are using the command draft. Here a draft is created with a scale 2:1 and using A4 size

DIFFERENT VIEWS OF CASING DESIGN MODEL

CONCLUSION

Sheet metal casing design is done with accurate scaling and following the industrial work flow