Advanced Sheet Metal Design Using NX Cad Challenge_1_Casing Design
Sheetmetal Casing Design
Part file:https://drive.google.com/file/d/1Hd1bTKQta1jBl1s4E47BGvO79xVibZBh/view?usp=sharing
Drawng file:https://drive.google.com/file/d/1YTKNB1vk-lVSzIt-s5bXYCW5t5NeDfOR/view?usp=sharing
Objective : The objective of this challenge is to create a Sheetmetal casing using the NX 11 Software. The tools within the software are used effectively to create the desired component within a minimum number of steps as possible. The sheetmetal is then folded out to create a flat pattern, whose image is placed in a drawing sheet to show the dimensions.
Introduction: Sheetmetal designing is one of the most versatile and important tools used when it comes to modern day production and manufacturing. Majority of the components used today are either partially or totally made up of sheetmetal, such as aircraft, car bodies, metal cabinets, Desktop CPUs and many more. The main advantage of using sheetmetal is that the resultant component is much lighter than a component made from other processes such as casting. Using sheetmetal also reduces material wastage and hence reduces the cost of a component.
Modern softwares such as NX 11 by Siemens is especially useful when it comes to optimising the workflow from designing to the manufacturing part. Softwares greately reduce the time and effort when designing new components by giving us the ability to modify and improve the design by trial and error, hence eliminating physical models. The component in this project is designed using NX to show the various steps in the process of sheetmetal design using datum tools.
Design Methodology : The flow chart below shows the design methodology.
Description:
First the new sheetmetal part file is opened and the global parameters within it is set (ex thickness of 1 mm). The part creation is started with the sketch of a rectangle (60 mm X 50 mm) in the XY plane. The tab is created using the tab feature. Since the thickness was specified in the global parameters, the tab thickness is automatically set to 1 mm. A rectangular cutout is made on one of the shorter edges using the normal cutout feature. Two lines are sketched, each 10 mm away from the longer edges and inwards. These lines specify the location for the next bending operation. The bend operation is applied to both the lines, with the bend angle of 90 degrees towards the positive Z direction. Then the flange operation is used to create flanges on the newly created bends. Two flanges are created on the side of the bend with the cutout, both 5 mm and 90 degrees to the bend surface (both flanges moving towards each other).The other two flanges are made on the opposite side of the bend without cutouts, both 5mm and 90 degrees to the bend, but moving away from each other. Break Corner operation is used to round the sharp corners present in the sheet metal. Now the pattern is flattened using the unbend feature, which is done by first fixing the base surface and unbending the remaining surfaces such that they lie in the same plane as the fixed surface. It is necessary to unbend so that other features such as holes and dimples can be made. After the unbending, sketches are made to specify the centres of the four holes that go in each corner. The holes are made using the Hole feature. The holes are given the specifications of depth (throughout), screw size (M2) and fit (H13). Next, a sketch is made in the middle of the base surface using sketch tools and spline feature. The resultant sketch is converted to a dimple using the dimple feature. This feature is used to create a raised or depressed surface on a flat surface. Bead feature is used to create a beaded surface using a sketch (5 mm circle) at four places. The component is folded back using rebend operation to show the final position of the bends. This completes the modelling part. The drafting process is started by first creating a flat pattern of the component using flat pattern feature. This is available in the part navigator list on the left. A new drawing file is opened in NX. The flat pattern is placed within the drawing sheet, showing the various dimensions and bend angles. The different views of the model are also placed by opening another drawing sheet within the same file.
Images:
Top View
Front View
Side View
Isometric View
Drawing sheets:
Flat pattern Drawing Sheet
Part Views Drawing Sheet
Conclusion: The sheetmetal component was designed using NX CAD software. The flat pattern was created and used to depict the various dimensions and bend angles used for the construction of the model. The various modelling features were used effectively to create the required part with minimal effort.