Challenge

Advanced Sheet Metal Design Using NX Cad Challenge_2_Box Assembly

AAkeel Shaikh14 Sept 2022

A Project Report

DESIGNING OF BOX ASSEMBLY USING SIEMENS NX SHEET METAL

Done by

R.PRAKASH

TABLE OF CONTENTS

S.NO	TITLE
1.	OBJECTIVE
2.	INTRODUCTION
3.	DESIGN METHODOLOGY
4.	DESCRIPTION
5.	PROCEDURE
6.	SCREENSHOTS
7.	DETAILED DRAWING SHEET IMAGE
8.	CONCLUSION

1. OBJECTIVE:

To design a Box Assembly using Siemens NX Sheet Metal.

2. INTRODUCTION:

NX™ software, the digital product development solution from Siemens, includes a set of state-of-the-art tools for designing sheet metal components. Using familiar terminology and workflows, NX Sheet Metal Design provides the design professional with a complete set of tools to efficiently create and manage sheet metal parts based on the knowledge of material properties and manufacturing processes. NX Sheet Metal Design tools incorporate material and bending information, enabling the model to represent both the formed component and flattened blank shapes.

The sheet metal design tools within NX allow companies to apply defaults – based on both industry and company best practices – to the values used in the creation of sheet metal parts. For example, bend radii and neutral factor values can be set to commonly used values to encourage re-use and save design time. Folded and unfolded views of sheet metal components can be used in both the 3D environment as well as downstream in 2D documentation and for manufacturing.

3. DESIGN METHODOLOGY:

4. DESCRIPTION:

SKETCH TOOLS:

Sketching is the process of creating a 2D drawing before developing it in 3D. In Siemens NX Sheet Metal, there are plenty of options and has various tools for creating a 2D sketch. In that, a few tools that are used for drawing the casing are discussed below.

STRAIGHT-LINE:

The straight line is one of the sketch tools which is used to draw a straight line. It creates lines with constraint inferencing.

ARC:

It creates an arc through three points or by specifying its centers and endpoints.

CIRCLE:

It creates a circle through three points or by specifying its centers and diameters.

RECTANGLE:

Creates a rectangle using any of three different methods.

POINT:

It is used to create sketch points in a 2D plane.

MIRROR CURVE:

This tool is used to create a mirror pattern of a chain of curves that lie on the sketch plane.

TAB:

It is used to create a base feature by extruding a sketch along a vector by a thickness value or adds material to a planar face. Additional planar selections can be added to generate bends as part of the base feature.

FLANGE:

It is used to add a flat flange at an angle to a planar face and adds a bend between the two.

BEND

It is used to modify a model by bending material on one side of a sketch line, adding a bend between the two sides.

BREAK CORNER:

It is used to create rounds or chamfers around sharp corners of a tab or flange

DIMPLE:

It is used to lift an area of the model inside a sketch that simulates a stamping tool.

BEADS:

It is used to lift the material along the contour of a sketch that simulates a stamping tool.

HEM FLANGE:

This is used to modify by folding the edge of a sheet metal flange over onto itself for the purpose of safe handling or to increase edge stiffness.

NORMAL CUTOUT:

It is used to create cut material by projecting a sketch onto the model and then cutting perpendicular to the faces intersected by the projection.

UNBEND:

It is used to flatten a bend and the material adjacent to the bend.

REBEND

It is used to restore an unbend feature to its previous bend state, along with any features added after the unbend feature.

5. PROCEDURE

5.1. DRAWING THE SKETCH IN SIEMENS NX SHEET METAL:

After opening Siemens NX 12 – Click on “New” Button - Select Sheet Metal – In the pop-up window select “Sheet Metal” – Click ok.
In the Sheet Metal Window – Click on “Sketch” and select XY Plane.
Click on “Rectangle Icon” located under “Direct Sketch Ribbon Bar” and draw a rectangle with the center at origin and having a length of 200mm in X direction and 150mm width along Y direction.
Exit the sketch mode.
Change the design parameters by going to Menu – Preferences – Sheet Metal and then in the “Sheet Metal Preferences” dialog box set all of the four Global Parameters to 1mm.

5.2. CREATING A TAB:

Click in “Tab” button to create a rectangular sheet metal of 1mm thickness.
By default, the section part will be highlighted and hence select the rectangular sketch which is drawn in the previous step – then click ok.
This will create a Tab of 1mm thickness.

5.3. CREATING MULTIPLE FLANGES:

Click on the “Flange” button – then select the inner edge of the two longest sides of the rectangle – give the ‘width option’ as Full – length as 70mm – Match face as ‘None’ – Angle as 90 degree – Length Reference as ‘Inside’ – Inset as ‘Material Inside’.
Under the “Bend Parameters” give the Bend Radius as ‘10mm’ and do not change the value of Neutral factor – Give ‘ok’ or else click on ‘apply’ and then give ‘cancel’.
Create another two flanges at 90 degrees along the shortest distance of the Tab but should be opposite to each other – give the length as 70mm – length reference as inside – Inset as Material outside – Give the bend radius as 10mm – click ok or else click apply and then click cancel.

5.4. CREATING CLOSED CORNERS:

Click on the “Closed Corner” located in the group titled “Corner” along the Ribbon Bar.
Select the type as “Close and Relief” – Under the bends to close select the edge of the tab which needs to be closed – select “Closed” for Treatment – Select ‘Closed’ for Overlap – Gap as ‘zero’.
Click ok or else click on Apply and then click Cancel.
Similarly, do it for the other side also.

5.5. CREATING MULTIPLE FLANGES:

Click on the ‘flange’ button – select the vertical inner edge of the flange previously created – give the Width option as Full – Length as 0.00199999mm – Match Face as ‘None’ – Angle as 90 degree – Length Reference as “Inside” and the Inset “Material Inside” – Bend Radius as “0” and leave the Neutral Factor as it is – Click on apply.
For the second flange – select the inner left edge of the newly created flange – width option as “Full” – Length as 6.5 – Match Face as None – Angle as 90 degree – Length Reference as Inside – Inset as Bend Outside – Bend Radius as 0.5mm and leave neutral Factor as it is – Click on apply
For the third flange – select the outer edge of the opposite flange – – width option as “Full” – Length as 0 – Match Face as None – Angle as 90 degree – Length Reference as ‘Web’ – Inset as ‘Material Inside’ – Bend Radius as 0mm and leave neutral Factor as it is – Click on apply
For the Fourth Flange – select the outer edge of the opposite flange – width option as “Full” – Length as 6.5 – Match Face as None – Angle as 90 degree – Length Reference as Web – Inset as Bend Outside – Bend Radius as 0.5mm and leave neutral Factor as it is – Click on apply and then click on cancel or else click on ok directly – this will close the command window.

5.6. CREATING MULTIPLE HEM FLANGES:

Create ‘Hem Flanges’ by clicking on the HEM Flange Icon located under the Group Titled “Bend”.
For the first HEM Flange - Select Type as ‘open’ – Select the edge of the previously created flange – Select Inset as “Bend Outside” – Bend Radius as 0.5 – Flange Length as 5 – Leave the Neutral Factor as it is – Click on apply.
For Second HEM Flange - Select Type as ‘open’ – Select the edge of the outside Flange – Select Inset as “Bend Outside” – Bend Radius as 0.5 – Flange Length as 5 – Leave the Neutral Factor as it is – Click ok or else click on apply and then click on cancel.
Adjust the Hem flanges so that it meets the requirement.

5.7. MIRRORING BODY:

Click on the “Mirror body” Button – select the entire body of the part – Under mirror plane – select the YZ plane – Activate all of the three settings available i.e., Select Associative, Fit at Current Timestamp, and copy threads – Click ok.

5.8. UNITING BODY:

Click on ‘Unite’ Command available under the Group titled “Features - Combine”.
Select the entire body part as Target – For Tool select the YZ plane – Click ok.

5.9. ADDING A DIMPLE & MIRRORING IT:

Click on the Dimple command available under the Group titled “Punch” – click on the sketch button available in the command window.
For the face or plane – select the front side of the part which is wider – sketch the 2D drawing of a cross as per the dimension – Mention all the constraints thus required to fully define the sketch – Click on ‘Finish’ in order to finish the sketch.
Now under the dimple command window – give the depth as 2mm – Side angle as zero degree – Depth Reference as Inside – Side Walls as Material Outside – Minimum Clearance as 5.0000mm – the dimple preview should create a dimple towards outer direction – if not then click on the button mentioned against “Reverse Direction” in the Dimple Command Window – then click ok.
Click on the Mirror Feature – Select the Dimple Cross thus created for Features to Mirror – Select the XZ plane for a Mirror Plane – Click ok.
Create another Rectangular Dimple of depth 2mm which is directed inward and is placed at the bottom rectangular plate of the part.

5.10. UNBEND & REBEND:

Click on the Unbend Button – For a stationary Face or Edge – Select the bottom rectangular plate of the Assembly box – then click, drag and select the entire model thus designed so far – This will unbend all the bends thus creating the flat sheet metal with bending lines visible.
Now click on the Rebend button – Click and select the entire box assembly – and then click ok.

5.11. CREATING A BEAD AND MIRRORING IT:

Now click on the bottom outer plate of the box assembly – Click on the Bead button available under the Group Titled “Punch” which could be seen on the Ribbon Bar.
Create the required Circular sketch of a given size – select the circular sketch for Stationary Face or Edge – Click on o

5.12. CREATING ANOTHER HEM FLANGES:

Create another set of HEM Flanges along the outer edges on the top side of the box assembly – Select the type as Closed – Select the Inset as Bend Outside – Give the flange length as 2mm.
Create similar types of HEM Flanges of the same size along all the remaining outer edges.

5.13. CREATING A DATUM PLANE:

Create a Datum plane by clicking on the “Datum Plane” located in the drop-down list box of the “Datum” Button at the beginning of the Ribbon Bar.
Select the type as ‘Inferred’ – Select the XY Plane for Objects to Define Plane – Enter the distance as 203mm – Make sure that the plane is created in an upward direction – if not then click on the ‘Reverse Direction’ Button available inside the ‘Datum Plane’ Command Window – Select the Number of Planes as ‘1’ – Click ok.

5.14. DESIGNING THE LID:

Create a new sketch on the newly created plane by clicking on the sketch button and then selecting the new plane thus created.
Click on the straight-line button available under the group titled “Direct Sketch” along the Ribbon Bar.
Draw lines along the border of the flanges thus created so far.
Create a Tab of thickness 2mm after closing all the gaps in the sketch.
Click ok.

5.15. CREATING MULTIPLE FLANGES FOR THE LID:

Create Multiple Flanges at 90 degrees along the outer edges of the lid by clicking on the ‘Flange’ button located under the group titled “Bend”.
For Base Edge – Select all the outer bottom edges of the lid – Select the width option as ‘Full’ – Length as 3mm – Direction should be downward if not click on ‘Reverse Direction button in the command window – Match Face as None – Angle as 90 degree- Length Reference as ‘Web’ – Inset as ‘Material Outside’ – offset as 0mm – and Bend radius as 3mm – Leave the default value of Neutral Factor as it is – click ok or else click on apply and then click on cancel.

5.16. CREATING HINGES

Create a sketch on the left side face of the box assembly by clicking on the sketch button and selecting the left side face.
Draw a Rectangle of approximate size whose right top corner is located at a vertical distance of 17mm from the top surface of the assembly box and having a horizontal distance of 3mm from the right side.
Create a Tab of thickness 1mm which is projected upward.
Create a fillet in the part by selecting ‘Break Corners” located under the group titled “Corners” along the Ribbon Bar.
For Edge to Break – Select the top left and right edges of the Tab thus created in previous sessions – Select Blend under Method and give the radius as 10mm – click ok or else click on apply and then click on cancel.
Create another flange created at the inner edge of the flange thus created – Width option as Full – Length as 4mm – Match Face as None – Angle as 40 degree – Length reference as Web – Inset as Material outside – Bend Radius as 0.5mm and leave the Neutral Factor as it is – Click on ok.
Create a hem flange – Type as open type – select the outer edge of the flange created in the previous step – inset as bend outside – bend radius as 5mm – sweep angle as 325degree – leave Neutral Factor as it is – click ok.
Unbend the entire flanges and hem flanges thus created so far.
Create a sketch on the unbend section – Draw four Rectangles located at a similar distance from each other – Exit the sketch – click on normal cutout – select the type as Sketch – Cut method as thickness – Limits as value – Depth as 5mm – click on ok.
Rebend again all the flanges and hem flanges.
Create a mirror body for the part thus created.
Create a Tab of thickness 1mm on the top of the lid.
Create break corners on the top two corners of the tab thus created in the previous step.
Create a flange of length 13mm – of bend radius 1mm – length reference as Web – Inset as material outside – Angle as 39 degree – Width option as full – click ok.
Create a hem flange of bend radius 5mm – sweep angle 325 degree – bend relief as square – depth as 3mm – width as 3mm – inset as bend outside & loop as open-loop – click ok.
Unbend all the flanges and hem flanges thus created.
Create four rectangles located at equal spaces on this unbend sheet plate.
Click on normal cut and remove the material inside of these rectangles.
Rebend again all the flanges and hem flanges.

5.17. ADDING COLORS:

Right-click on each side of the assembly box – select “Assign Feature Color” – and then click on the required color – click ok.
Repeat the same procedure to change the color of the different parts of the box assembly.

Multiple Views -

Top View -