Week 4 -Wire Bending Challenge
Week 4 Challenge: Wire Bending Challenge
Course: Structural Analysis Using Ansys Workbench
Submitted by: Amanpreet Singh Whan
Supervisor: Vineet G
March 11, 2022
List of Figures
Figure 1- Wire Bending Process.
Figure 2-Static Structural Analysis workflow for case 1.
Figure 3-Static Structural Analysis workflow for case 2.
Figure 4-Static Structural Analysis workflow for case 3.
Figure 5-Imported given CAD Model.
Figure 6-Face Sizing selected for the highlighted faces of the given Model.
Figure 7-Face Sizing selected for the highlighted faces of the given Model.
Figure 8-Meshed given CAD Model.
Figure 9- Fixed Support defined for the face of the wheel model.
Figure 10- Fixed Support defined for the face of the wire model.
Figure 11- Joint Rotation Load defined for the Lever model.
Figure 12-Frictional Contact defined between faces of the given model.
Figure 13-Modified Structural Analysis Settings.
Figure 14- Procedure to be followed to calculate results.
Table of Contents
3.1 Importing and Meshing of CAD Model
1 Introduction
ANSYS is a general-purpose, finite-element modeling package for numerically solving a wide variety of mechanical problems. These problems include static/dynamic, structural analysis, heat transfer, and fluid problems, as well as acoustic and electromagnetic problems. There are two methods to use ANSYS. One method is to use the graphical user interface (GUI). This method follows the conventions of popular Windows and X-Windows-based programs. Another method is to use command files. The command-file approach has a steeper learning curve for many, but it has the advantage that the entire analysis can be described in a small text file, typically in less than 50 lines of commands. This approach enables easy model modifications and minimal file-space requirements. The ANSYS environment contains the main window and an output window. A large number of files are created when ANSYS simulation is run.
Theory
Wire forming is a method for applying force to change the contour of wire by bending, swaging, piercing, chamfering, shearing, or other techniques. The various techniques for wire forming can produce any type of shape, form, or configuration. The process starts with a coiled wire that is straightened before being formed.
Methods Used for Wire Forming:
Though several types of equipment are used to perform wire forming, in most cases, wire forming machines are manually or automatically operated. Manual machines include ones that are operated by manual force and ones that are electronic but manually loaded. Automatic machines have advanced computer numerically controlled (CNC) programming and complete production without manual involvement.
Manual Wire Forming: The oldest method for wire forming is manually operated machines, which involves a hand lever and spindle. Manual machines can be drawn or rotary die and have gears that increase the applied bending force.
Coil Wire Forming: Coil, or spring wire forming, involves winding wire around a metal blank. It is also used for the manufacture of electrical coils where a conductive wire is evenly wound around a ferromagnetic core. Coil winding takes different forms depending on the final product. Electrical coils have to be more precisely wound than springs and can require more than one winding.
Roll Wire Forming: Roll forming is a cost-efficient method for the production of flat, round, and other shapes of wire parts. The process can manufacture undercuts, knurls, pointing, chamfers, grooves, surface finishes, collars, and threads. Roll-formed wire parts have extra strength after being hardened, having rounded edges, and being pre-finishing.
Bend Wire Forming: In the wire bending process, the wire can be shaped into unlimited configurations to fit any application. Diameters of 0.4 mm to 16 mm, or 0.016 into 0.625 in, can be easily formed. Since the bend in the wire is made before the wire is cut, the process has no scrap or waste and does not need secondary finishing.
Fourslide Wire Forming: Fourslide forming or stamping uses the same process as a horizontal stamping press with the addition of cams. Along with the cams, the machine has shafts, an electric motor, a die, a press, and sliding tools. The process has four sliding tools that form the wire from four sides. The cam regulates the movement of the four tools, which allows the process to have vertical movement, such as punching, with a horizontal movement in several directions.
Hydraulic Wire Forming: A hydraulic motor is used to drive the shaping rollers in a hydraulic wire forming machine. A servo motor and CNC programming program the machine to the required configuration. Wire shapes are automatically discharged from the machine after the completion of the operation.
Pneumatic Wire Forming: In the pneumatic process, wire is fed into the straightening machine, formed to the required shape, and pneumatically cut to the proper length.
CNC Wire Bending: CNC wire bending machines can be pneumatic or hydraulic for efficient and rapid production. They can bend and shape rebar to 180o using single or double wire. The machine straightens the bar before the bending process. CNC machines have exceptional accuracy and cut wire to the exact required dimensions. The types of wire a CNC machine can be programmed to shape include music, hard drawn, basic or coated metals, 300 series stainless steel, brass, and beryllium copper. Wire diameters vary between 0.008 into 0.250 in or 0.0203 mm to 6.35 mm.
2 Aims
- Simulate Wire Bending using three different materials for the given Model.
- Refine the Mesh Size and compare the directional deformation results.
- Apply appropriate Boundary Conditions and Joint Loads.
- Lastly, Determine Total Deformation and Maximum Stress results for the performed simulations and compare the results for the same.
3 Methodology and Results
The section describes the different stages that were performed using an engineering tool Ansys Workbench 2022 for the completion of the Week 4 Challenge. These stages can be further broadly sub-categorized into three key steps, importing the CAD model to apply the boundary conditions and finally performing the simulation to obtain the desired results.
3.1 Importing and Meshing of CAD Model
After opening the Ansys Workbench, the first step is to select the Analysis type and then define appropriate material from the Engineering Data options for the given CAD model. Considering the challenge requirements, Static Structural was selected for the System Analysis type while three different materials such as Aluminium Alloy 1199, Copper Alloy NL, and Magnesium Aloy NL were selected for the challenge purposes. The following figures highlight the analysis system and material card parameters in detail.
After updating the CAD model in the Ansys Workbench, the next step is to generate a good quality mesh. Meshing is a phase where the CAD geometry is discretized to represent the computational domain in which the solver will discover a solution. A refined mesh helps to achieve better results. The mesh was generated in three steps: the face sizing method with an element size of 1.8 mm and 0.8 mm was used to refine the faces in contact; for other areas in contact the mesh was generated using default element size.
3.2 Boundary Constraints
Boundary conditions are constraints necessary for the solution of a boundary value problem. The Fixed support constraint restricts all the translation degrees of freedom over the assigned entities to be zero. The force boundary condition applies a distributed force to the structure. It can be assigned to any number of faces of a structure. This boundary condition works as surface traction on each element of the assigned topological entity and its value is proportional to each element’s area.
Two fixed supports and joint rotation constraints are assigned to fulfill the challenge requirements. The process followed to assign the boundary constraints is presented in the following figures.
3.3 Contact
In structural analysis software, the contact is generated by pair. Three different contact behaviors are available. They are named node to node (point to point), node to the surface (point to the surface), and surface to surface. As default in Ansys software, point to surface and surface to surface contact types are used. For the point to surface contact, the “point” is contact, and the “surface” is the target. Several contact types are used. These names might be called with different names according to software. In Ansys software, contact names are titled frictional, frictionless, rough, bonded, and have no separation. The Frictional Contacts were defined for the challenge purposes and are represented in the following figures.
3.4 Analysis Settings
The given spur gear model was simulated for a total number of 8 steps to determine appropriate total deformation and other stress-strain results. Therefore, the Large Deflection option was turned on to prevent Penetration and Intersection errors. The following figure represents the modifications performed in the analysis settings.
Simulation Results
To visualize the simulation or results, the desired output cards have to be created. Total Deformation, Equivalent Elastic Strain, and Equivalent Stress (Von Mises Stress) cards were created using the procedure illustrated in the following picture. It must be noted that the results have to be generated by running the solve command.
Case1: Simulation Results of Model having Copper Alloy NL Material
Deformation Results:
Strain Results:
Stress Results:
Contact Tool Results:
Case2: Simulation Results of Model having Aluminium Alloy NL Material
Deformation Results:
Strain Results:
Stress Results:
Contact Tool Results:
Case3: Simulation Results of Model having Magnesium Alloy NL Material
Contact Tool Results:
Strain Results:
Stress Results:
Contact Tool Results:
4 Conclusion
In conclusion, the main aim of the Week 4 challenge was to Simulate Wire Bending using three different materials for the given Model. From the results, it was found that the total deformation resulted in all cases is the same. The elastic strain resulting in case 1 is minimum in comparison to case 2 and case 3. However, the maximum stress resulting in case 3 is minimum in comparison to case 1 and case 2.
In conclusion, the wire having Magnesium Alloy NL material should be selected for the real-life scenario since it has yielded better stress-strain simulation results.