Inverse Modeling of Injection Molding Thermal Stresses to Optimize Temperature and Pressure History

1996 ◽  
Vol 11 (2) ◽  
pp. 167-178
Author(s):  
Y. Farhoudi ◽  
M. R. Kamal
Keyword(s):  
Injection Molding ◽  
Inverse Modeling ◽  
Thermal Stresses ◽  
Pressure History ◽  
Temperature And Pressure

scholarly journals Design, Analysis and Fabrication of Safe Holder and Cam Dies in Injection Molding

2020 ◽  
Vol 8 (6) ◽  
pp. 4070-4077
Keyword(s):  
Injection Molding ◽  
Material Flow ◽  
Manufacturing Industry ◽  
Solid Material ◽  
Design Analysis ◽  
Simulation Software ◽  
Analysis Software ◽  
Flow Temperature ◽  
Mold Making ◽  
Temperature And Pressure

Injection molding is one of the very significant methodologies in the plastic manufacturing industry. Production of any shape in the injection molding, mold with cavity must require. For this mold making three phases were involved in this project starting from design, analysis, manufacturing respectively. The objective of this project is to introduce detailed steps on design mold and using the simulation software to analyze the material flow, temperature and pressure characteristics of the product. The product designed and analyzed for this project is SAFE HOLDER and CAM. The manufacturing of mold is done by using advanced machinery such as CNC. The design and analysis of this product and mold were made by the designing analysis software CATIA V5, ANSYS 15.0, which is then stimulated by the use of Fluid Flow (Fluent) tool. This project was very useful in knowing the fluid characteristic behavior subjected to flowing inside the mold and also observed the variation of values with respect to given values at each stage. In this project, the analysis performed with taking polypropylene as a fluid from propylene polymer and steel as solid material for the die with inlet values are 230℃ temperature and 15m/s velocity.

Nature of contact between polymer and mold in injection molding. Part II: Influence of mold deflection on pressure history and shrinkage

2000 ◽  
Vol 40 (7) ◽  
pp. 1692-1700 ◽  
Author(s):  
D. Delaunay ◽  
P. Le Bot ◽  
R. Fulchiron ◽  
J. F. Luye ◽  
G. Regnier
Keyword(s):  
Injection Molding ◽  
Pressure History

Effect of Thermal Barrier Coating on Piston Crown for Compressed Natural Gas with Direct Injection Engine

2011 ◽  
Vol 52-54 ◽  
pp. 1830-1835 ◽  
Author(s):  
A.J. Helmisyah ◽  
Shahrir Abdullah ◽  
Mariyam Jameelah Ghazali
Keyword(s):  
Heat Flux ◽  
High Temperature ◽  
Natural Gas ◽  
Thermal Stresses ◽  
Direct Injection ◽  
Thermal Barrier ◽  
Compressed Natural Gas ◽  
Piston Crown ◽  
Barrier Coating ◽  
Temperature And Pressure

The top land of a piston normally known as the piston crown is an engine part that is continuously exposed to extreme temperature and pressure during combustion. For a compression ratio level, the compressed natural gas with a direct injection system (CNGDI) typically uses a range of compression ratio between gasoline and diesel engines, producing extremely high temperature and pressure which lead to high thermal stresses. Consequently, the piston crown is exposed to direct combustion due to the vertical movement of the piston, leading to various possible damages of thermal stresses. In contrast to a petrol fuelled internal combustion engine, natural gas combustion creates a dry condition in the combustion chamber, inducing cooling difficulties in the engine. Without good heat transfer, the piston crown materials will soon fail to withstand high temperature and operate effectively. Alternatively, any sort of insulation inside the combustion chamber such as applying ceramic coatings may protect the piston crown surface and affect the overall combustion process, as well as improving the engine performance and the exhaust emissions. By reducing the heat loss of a cylinder bore, a higher thermal efficiency of an engine can also be improved by applying a surface thermal insulation, namely; thermal barrier coating (TBC). Thus, in this study, a ceramic based TBC, yttria partially stabilised zirconia (YPSZ) coating was used to compare with conventional tin coated (Na2SnO3) and uncoated piston crown in terms of heat concentration. Moreover, a set of average value of combustion temperature of a CNGDI engine was selected. Detailed analyses using a finite element analysis (FEA) technique was utilised in order to determine the location of hotspots via distribution profiles of temperature. It was noted that the maximum heat flux of the uncoated piston crown was much higher than that of tin coated and YPSZ coated piston crown. Heat flux value reached about 62% of decrement due to lower conductivity levels of piston crown.

Temperature and pressure evolution in fast heat cycle injection molding

2018 ◽  
Vol 34 (4) ◽  
pp. 422-430 ◽  
Author(s):  
Sara Liparoti ◽  
Andrea Sorrentino ◽  
Giuseppe Titomanlio
Keyword(s):  
Injection Molding ◽  
Heat Cycle ◽  
Temperature And Pressure ◽  
Pressure Evolution

Changing Fossil Unit Startup Process Reduces Rotor Stresses

2008 ◽  
Author(s):  
Craig Jennings
Keyword(s):  
Thermal Stresses ◽  
Energy Market ◽  
Steam Turbines ◽  
Steam Temperature ◽  
Thermally Induced ◽  
Start Up ◽  
Hot Start ◽  
Startup Process ◽  
Temperature And Pressure ◽  
Main Steam

The changes in the energy market dispatching and pricing, have increased the need to start fossil steam turbines faster to meet demand and save fuel. Exelon worked with a consultant to optimize the start up times of their steam turbines resulting in greatly reduced start up times, increased dispatching frequency, and reduced thermal stresses on the turbines. This optimized start up process was achieved by utilization of the Valve Open Start (VOS) and Accelerated Hot Start (AHS) process. VOS utilizes condenser vacuum aligned to the steam generator to produce superheated steam at much lower temperatures and pressures than usual. This steam is drawn through the turbine to warm the unit while the boiler increases in temperature and pressure. The AHS changes the startup sequence of operations by setting up the turbine in a manner that allows the turbine to roll at precisely the time that a perfect temperature match is obtained between the main steam temperature and first stage metal temperature. The use of these processes significantly increases profitability of the units and meets all OEM criteria for unit protection and results in a reduction in rotor thermal gradient, temperature mismatch, and thermally induced vibration.

Sign in / Sign up

Export Citation Format

Share Document