Process Data

This step allows you to specify the details of the forging process. At present, press forging and radial forging are supported.

Process Builder

In the Process Builder, you will enter the information about each forging /reduction stage. For each stage, the key parameters such as forging process, reduction, the tool set (must have been already defined in the previous step) used for this stage are specified. In addition, you should also specify the feed sequence in which the work piece is hit by the forging punch. All parameters specific to the forging stage are explained below.

process_builder

Name	Description
Forging Process	At present, only Radial Forging and Press Forging are supported.
Billet Orientation	It is the direction in which the work piece is advanced during the forging process. The default is Z-Axis (positive) direction.
Forging Full Billet	It tells whether the forging is performed over the entire length of the billet. The allowed options are Yes/No. At present, only option Yes is supported, that means only full length of the billet is forged. The other option is included to allow forging only a portion of the billet in future.
Reduction	Amount of reduction achieved in the characteristic dimension of the billet (in case of a circular billet, it is reduction of diameter)
Initial Diameter	For the first stage it is the same as the original billet diameter. And for the subsequent stages, the initial diameter for the current stage is equal to the billet diameter at the end of the previous forging stage.
Final Diameter	For the current stage Final diameter is the diameter of the billet at the end of this forging stage. Final Diameter = Initial Diameter – Reduction
Tool Set	Tool set should be selected according to the current forging process. If the forging process is Radial Forging, you should select the tool set for the radial forging. And moreover this tool set must have been defined during Tool Components step under Model Data.
Sequence 1	Sequence1 and Sequence2 describe how the billet moves during the forging process. For example, if Sequence1 is specified as Rotation and Sequence2 as Translation , first work piece is rotated with a specified Rotation Angle between two consecutive punch blows until reduction is applied over the entire circumference of the workpiece. Then workpiece is advanced in BilletOrientation direction with a specified feed rate.
Sequence 2
Rotation Angle	Indicates the angle at which workpiece rotates between two consecutive punch blows
Steps per Rotation	Number of rotation steps the workpiece should undergo in order to ensure that it is hit uniformly along the circumference.
Strokes per Min	Number of punch strokes per minute.
Die Travel Distance	The distance a die (punch) travels freely before hitting the workpiece.
Feed Rate	The distance the workpiece advances in the translation direction in each translation step.
Rotation Direction	It specifies the rotation direction of the workpiece during the forging process. Valid options are Clockwise, Counterclockwise and No Rotation.
Feed Overlap	It determines the position of the billet at the start of forging process for the current stage. The billet is positioned such that the end of the billet is at a distance equal to Feed Overlap inside the punch in Billet Orientation Direction at start of each forging stage. Feed Overlap value should be carefully selected to ensure the billet is uniformly hit over the entire circumference before it elongates beyond the punch.

Each Forging Stage information is exported as a separate data packet in a *.grf file as shown below.

ForgingStage Stage1 {
Process	= "RadialForging"
BilletOrientation	= "Z_Axis"
ToolSetName	= "Tool1"
ForgingFullBillet	= "Yes"
Reduction	= 20.0
FirstFeed	= "Rotation"
SecondFeed	= "Translation"
RotationAngle	= 22.5
RotationDirection	= "Clockwise"
NumRotationSteps	= 4
PunchStrokesPerMin	= 55
PunchTravelDistance	= 22.0
FeedRate	= 300.0
FeedOverlap	= 200.0
}

Total simulation can comprise several forging stages. The number of forging stages and sequence in which the forging stages are performed are exported as a ForgingSequence data packet.

ForgingSequence ForgeSequence {

NumForgingStages = 4

Sequence = "Stage1" “Stage2” “Stage3” “Stage4”

}

Process Parameters

Process parameters are arranged in four different groups, each under a separate tab.

Note: The process parameters under these tabs are exported into *.frg file.

Process parameters, for which you will specify values different from corresponding default values will surely be written in the *.frg file. Otherwise only critical process parameters are written in *.frg file. For those parameters that are not written in *.frg file, default values are applied by the solver.

The Session tab contains the information about the nonlinear tolerance and maximum number of nonlinear iterations.

forging_wizard_process_param

Name	Description
Process Type	Type of process is HX-Forge.
Job/Model Name	Name of the job. This text is used to form file names, therefore follow the naming standards that correspond to your operating system. Avoid using spaces, tabs, and other special characters.
Nonlinear Iteration Tolerance	Tolerance for nonlinear iterations. The default value is 0.001. This value defines the convergence criteria for nonlinear iterations.
Maximum Nonlinear Iterations	Maximum iterations per time step. Nonlinear iteration loops stop when the convergence criterion set by Nonlinear Iteration Tolerance is met. If the solution is not convergent, the loop will stop when it reaches this maximum value. The default value is 25.
Autosave Frequency	Frequency at which the solution should be saved to the *.phx file. The default value is 1.

forging_wizard_hxforge

Name	Description
Analysis Type	In case of forging, Analysis Type is always TransientMovingBoundary.
Forging Analysis Type	At present, only Open-Die Forging is supported.
Forging Direction	The direction in which work piece translates during forging process. The default is Z-Axis.
Initial Billet Diameter	The diameter of the billet at the beginning of forging process.
Initial Billet Length	Length of the billet at the start of forging process.
Billet Preheat	Billet pre-heat temperature. This parameter is used as the initial condition for the analysis in the case of transient runs.
Work Converted to Heat (%)	Percent of mechanical energy converted to thermal energy. Percent of mechanical energy converted to thermal energy. The default value is 90 percent .
Time Steps per Stroke	Number of steps used in the calculation between two consecutive punch blows. This parameter is added to ensure better convergence of the solution algorithm.

This tab contains the advanced parameters such as relaxation factors used in temperature, velocity, and pressure calculation.

Name	Description
Relaxation Factor - Velocity	Weighting factor for velocity relaxation. See Relaxation Factors.
Relaxation Factor - Temperature	Weighting factor for temperature relaxation. See Relaxation Factors.
Relaxation Factor - Pressure	Weighting factor for pressure relaxation. See Relaxation Factors.
Relaxation Factor - Strain	Weighting factor for strain relaxation. See Relaxation Factors.
Strain Calculation Method	This parameter is automatically set to Galerkin.
H3D File Save Frequency	When performing a transient analysis, you can avoid saving the solution in the H3D file at every time step to reduce the file size. Use this parameter to specify the time interval to be used for saving the file. For example, if the frequency is 4, the solution will be saved at every fourth step (4, 8, 12, etc.) The default value is 1.
Memory for Solver	Used to specify in-core/out-of-core RAM memory usage by the linear equation solver. The default is 128 MB. If N is set to 0, the solver will use only out-of-core memory. N can be set to -1 to force all in-core calculations by the solver. In this case, the machine should have enough extra RAM to load the code and the database.
Reserved Memory Size	This parameter is used to determine the amount of memory needed by HX-Forge. This parameter is valid only for 64-bit Linux machines and it is ignored for all other platforms. There are two parameters that deal with allocation of memory: MemoryForSolver, and ReservedMemorySize. Of these, MemoryForSolver is also included in ReservedMemorySize. Therefore, MemoryForSolver should be less than ReservedMemorySize. For example, if the MemoryForSolver is 512 MB and ReservedMemorySize is 2048 MB, the 2048 MB includes the 512 MB in its count, which means, after taking 512 MB for the linear solver, only 1536 MB is available for the remaining solver needs. This is a fixed amount and cannot grow dynamically during the run. However, even if you allocate only 512 MB for MemoryForSolver, that can expand without affecting the rest during run time. So, if you want increase the size, leave the MemoryForSolver to the default value of 512 MB in the HX-Forge interface and increase only the ReservedMemorySize. Because ReservedMemorySize is specific for 64-bit machines, it is usually not a problem to overestimate this parameter. It must be set to less than the total amount of swap space, but it can be safely set even higher than amount of physical RAM. The HX-Forge Interface will try to estimate this value based on the size of the mesh. However, this estimate is based on thumb rule and sometimes may not be adequate. Depending on the computing capacity you have, you can increase this number in the Tcl file. In addition to the value specified in ReservedMemorySize, HX-Forge uses some additional memory for its database and post-processing (if used). The size of the database will be approximately the size of the autosave file. Note: if you make the ReservedMemorySize very large without reason, you will end up monopolizing the machine (thereby denying memory to other processes) or PBS servers may place your job far behind in the queue. Type: Integer Minimum: Should be greater than 1024, or at least 1.67 times the MemoryForSolver. Maximum: depends on the size of the RAM and swap space

On this tab, you can set advanced numerical parameters used by the solver.

forging_wizard_advanced

forging_wizard_user

Process Data

Process Data

Process Data

Process Builder

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Process Parameters

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