| Home | My Account | Post Article | Upload Showcase | Site Shortcuts | Feedback | About us |

  Home > FE Modeling Project >

 
Seven Tech
Pat. Warn
Pat. Level2
Upgrade
Diagnosis
Consulting
Models
Prj cases
Model Sys
New L2
Modeling
Ind. Softw.
Simulation
Key Prjs
Li-Battery
Smart Equip
Model Prjs
Manufact.
Li Batt Ind.
Steel Ind.

Company

Defect Warn

Equip Intelli

Domain Sale

Training

- Class Time
- Classes
- Resources
- Lrn Method
- Status Need
- Metaverse
- Li Batt Tech
- Equip Softw.
- Intelli System
 



FE Modeling in Hot Rolling of Steel Sections
(Funded by DFG, the German Research Association)

 

<Continue>
 

I.Application of finite element simulation to optimize the pass design of section steel


1 Brief introduction of the finite element model for hot rolling of section steel funded by German Research Association

The finite element model can be an independent software package without other source programs, or a software package deeply developed based on existing source programs. Because the elastic-plastic model of hot rolling of complex section steel is very complex, the independent software package developed from scratch often has various weaknesses, including simplification of algorithm (such as non elastic-plastic) or weak data input interface. The model introduced here is a software package deeply developed based on Marc source program. The development of this model lasted six years, with nearly 10 participants and a cost of about 500000 US dollars, including five years (model development, model verification, proposal and development of simplified model) presided over by our experts and one year's work on simplified model verification by another colleague (now presided over Sim's model development). After that, it was further optimized in more than ten years, including the cooperative development with Marc company. See the following model development process. The model is characterized by exquisite modeling, high degree of optimization, high precision and fast operation speed.

The technical software package of this model includes:

  1. A complete set of input program prepared for MARC source program adopts elastic-plastic thermodynamic model and is based on Lagrange algorithm (omni-directional simulation, not local), including the technical and data details of the following items.

  2. A complete set of meshing and optimization technology. Because the section shape is very complex, how to use the best designed mesh to improve accuracy and save time has a high technical content. This part of the technology includes grid design, grid initial division, and grid re division in the process of operation, etc. This technology designs each pass grid and its optimization according to the final rolling shape, in order to achieve the best operation accuracy for the same amount of calculation. Some modelers optimize the mesh from the initial shape, and some even use the automatically generated mesh, which is not desirable because it can not achieve the best effect.

  3. Physical performance parameters basically change with temperature at high temperature. Of course, these physical performance parameters are different for different classes. This software package includes the changes of physical performance parameters of each class rolled by customers with temperature in the corresponding temperature range. The amount of data depends on the list of categories provided by the customer and the temperature range. Metal Pass has a complete database of metal high temperature properties; The content of the database is data collection and material performance modeling all over the world for more than 20 years.

  4. Mechanical property parameters, such as flow stress, Young's modulus, Poisson's ratio, etc. These parameters change with temperature at high temperature, and the data of each steel type are also different. Flow stress is also related to deformation, deformation speed and grain size.

  5. Data or prediction model of rolling boundary conditions. Before finite element modeling, a complete set of models need to be established to predict the boundary conditions of the rolling process. For example, the heat transfer coefficient between roll and metal is restricted by a series of factors, which changes between 2500-12500w / m ^ 2K. It is more complicated when there is cooling water. Even in air, the heat transfer coefficient depends on the relative velocity with air, and so on. These need accurate models to calculate.

  6. Temperature treatment during multi pass rolling in the deformation field. The temperature shall be non-uniform, even when the steel moves from the furnace to the roll in the first pass, the temperature of its section has been non-uniform. Usually, the deformation of metal is large in the high-temperature area and small in the low-temperature area. When the input temperature field is inaccurate, the section shape is wrong.

  7. Definition, input and output of steel rolling process parameters. Finite element source programs such as Marc do not involve special parameters for steel rolling, such as pass reduction rate, rolling speed, rolling force and torque, and so on. These special parameters for steel rolling must be defined and input in the subroutine. Then the calculated results can be displayed and expressed by Marc display function block (post processor). Some other parameters, such as the shape of projection deformation zone, can also be calculated and displayed.

  8. High end function: microstructure simulation. If there is a problem with the uniformity of mechanical properties of the product, the finite element can calculate and display the distribution of internal microstructure parameters, such as the degree of recrystallization, the distribution of grain size with cross section and so on. This part of the achievement was developed by the experts of the company while working at Morgan.

  9. A set of coordinated parameter settings to make the model run smoothly and achieve high prediction accuracy. For example, the optimal mesh size and the related time step, and so on. This is the area that needs to be tried the most in the initial modeling, and it is also an extremely complex field. It is very difficult to simulate hot-rolled section steel by finite element method. The model stops running halfway when the conditions are slightly uncoordinated. The initial modeler often needs half a year to a year to make the model run smoothly to the natural end (rather than accident interruption).

  10. A series of optimization and treatment measures can save time and have high accuracy. For example, the mesh of steel not in the deformation zone can be thicker. Here, the company has a number of optimization measures, which can be provided according to the needs of users.

  11. Automatic generation of input model parameters. Finite element source programs such as Marc need an input file that contains all the input data. Generally, after generating the grid, users can manually input various boundary conditions and material parameters through the user interface of the source program, and select the time step. These data can be automatically inserted through external software packages. External software packages can greatly reduce the difficulty and workload of modelers through their own user interface and a series of databases (as described above).

  12. Combination with pass design software package. If the above external software package is taken as a part of the pass design software package, the pass design and finite element simulation will be connected. This led to a technological leap. This is the beginning of the development of pass design software package of this project. A series of optimization measures, such as the intelligent essence of modern automation control software? Self study optimization, etc. will be added to this pass design software package.

Everyone's modeling methods and experience are different, and the quality of the results is very different. If the model is inaccurate, it will lose its guiding significance and mislead the design. This finite element model software package can enable inexperienced modelers to obtain good simulation results in a short time. Moreover, this software package may interface with the pass design software and make a revolutionary leap in the pass design level.

<To be continued>

 

<previous> | <next>

|  Part1  |  Part2  |  Part3  |  Part4  |  Part5  |  Part6  |  Part7  |  Part8  |  Part9  | 


  | Private Policy | Terms & Conditions | About Us | AdvertisePartnerInvestorSponsorlistings |  
Copyright: 2022 Metal Pass LLC. All right reserved