One Action Press Forming of Helix Bevel Gear by Using Multi-Cylinder Press and Die Heating System

2018 ◽  
Vol 12 (5) ◽  
pp. 767-774
Author(s):  
Katsuaki Nakamura ◽  
◽  
Hiroshi Koresawa ◽  
Hiroyuki Narahara
Keyword(s):  
Hot Forging ◽  
High Hardness ◽  
Heating System ◽  
Bevel Gear ◽  
Cold Forging ◽  
Machining Time ◽  
Forging Process ◽  
Forged Parts ◽  
Almost All ◽  
Forging Press

In the case of a complex shaped helix bevel gear, the forging of complete gear tips is very difficult to achieve. In almost all cases, tooth profile is finished by cutting machine from simple shaped forged parts, therefore requiring considerable machining time and cost. However, there are many approaches to forging. Forging is mainly classified as hot and cold forging, and uses a single motion press. In the case of hot forging takeoff of products from die is difficult by the cooling shrinkage from die and accuracy of products is lower level than cold forging. In addition, in the case of cold forging, a complicated shape is difficult to achieve based on the lack of ductility of the materials. To realize a helix bevel gear using a single forging operation, we applied a tool heating system and three-axis forging press. The tool heating system is applied to prevent a temperature decrease in the material by contact between the tool and forging material during the forging process. Further, to optimize the forging direction and timing, we used a three-axis forging press. We confirmed good forging capability of this special forging process, as well as the high precision of the forged parts. Moreover, through the thermo-mechanical control of steel and the tool temperature, the forged parts showed good mechanical properties, such as high hardness.

Numerical Simulation Analysis on Cold Closed-Die Forging of Differential Satellite Gear in Car

2008 ◽  
Vol 575-578 ◽  
pp. 517-524 ◽  
Author(s):  
Yao Zong Zhang ◽  
Jian Bo Huang ◽  
Xue Lin ◽  
Quan Shui Fang
Keyword(s):  
Numerical Simulation ◽  
Simulation Analysis ◽  
Simulation Software ◽  
Bevel Gear ◽  
Cold Forging ◽  
Forging Process ◽  
Die Forging ◽  
Closed Die Forging ◽  
Forming Defects ◽  
Deform 3D

The cold closed-die forging process of the gear is a kind of new technique of the precise forming of gear in recent years. In this paper, the cold closed-die forging process of differential satellite gear in car was analyzed through numerical simulation method. Forming mold was designed with Pro/E Wildfire2.0 which included four components : upper punch, lower punch, tooth shape upper die and lower die for Normal Cone. The three-dimensional models of satellite bevel gear mould were built and imported into numerical simulation software DEFORM-3D. Because the gear has the uniform circumferential features, in order to save time and improve the accuracy, only one tooth was simulated, and the full simulation outcome of 10 teeth was mirrored from this one. Through the numerical simulation analysis of DEFORM-3D, the instantaneous deformation and stress filed were gained. Forming defects were forecasted and the cold closed-die forging rule for satellite gear used in car was obtained which can provide effective references for no-flash cold forging process of planet bevel gear and the mold design.

Study on the Crack Forming during Cold Forging Process of ML25Mn Steel

2012 ◽  
Vol 184-185 ◽  
pp. 1255-1258
Author(s):  
Zhuang Li ◽  
Di Wu ◽  
Wei Lv
Keyword(s):  
Chemical Composition ◽  
Surface Quality ◽  
High Hardness ◽  
Complex Oxides ◽  
Cold Forging ◽  
Internal Defects ◽  
Forging Process ◽  
Sem Observation ◽  
Metallic Inclusions ◽  
The Matrix

The important factors that affect the formability of the cold forging steel are its surface quality and internal defects. The cracking phenomenon was taken place during cold forging of ML25Mn steel. In this study, microstructural analyses were made on around the cracked regions of the steel. The reason of cracking, which occurred during cold forging for ML25Mn steel, was investigated based on SEM observation in detail. The results have shown that the crack forming during cold forging process is not related to the chemical composition for ML25Mn steel. Cracking is not resulted from high hardness of the steel rods. There are some non-metallic inclusions in the matrix of ML25Mn steel, and the film-like inclusions are composed of MnS, CaS and complex oxides containing Mg, Al, Mn, Fe, S, Ca and O. The formation of non-metallic inclusions is the result of the deoxidation and the solidification during smelting and casting of steel.

scholarly journals Automotive CVT sheave development using complex forging processes

2018 ◽  
Vol 7 (3.3) ◽  
pp. 329
Author(s):  
Wen Kun Peng ◽  
Sung Young Park
Keyword(s):  
Metal Flow ◽  
Hot Forging ◽  
Tensile Tests ◽  
Machining Process ◽  
Product Development Process ◽  
Cold Forging ◽  
Forging Process ◽  
Flow Test ◽  
Core Part ◽  
Material Cutting

Background/Objectives: In this study, we developed a complex forging process to produce a sheave, which is a core part of CVT for automobiles, fabricated prototypes. The existing processes such as hot forging and the MCT machining process have disadvantages including excessive amounts of material cutting, number of processes, and processing time.Methods/Statistical analysis: To overcome these shortcomings, in this study, a shape was created using hot forging and the shape was molded into a precision part using cold forging. A complex forging process was developed that enabled maximization of the metallographic density and reduction of material cutting quantity by applying a minimal number of processes. By conducting heat compression and tensile tests of the samples, we identified the physical properties of the material and used the commercial software Deform-3D to conduct a forging analysis.Findings: Based on the analysis results, we designed a combined process of hot forging and cold forging and fabricated a mold and pilot products. The fabricated pilot products were evaluated using a metal flow test, an internal defect test, a surface roughness test, etc. According to the evaluation results, no significant defect was observed, and we therefore believe it is adequate for mass production.Improvements/Applications: The complex forging method can reduce the use of material by approximately 15% compared with the hot forging and the MCT machining process. Through this study, we established a product development process using a high-precision complex forging technology.  

scholarly journals Case Study of the Effect of Precoating on the Decarburization of the Surface Layer of Forged Parts during the Hot Die Forging Process

2020 ◽  
Author(s):  
Paweł Widomski ◽  
Maciej Zwierzchowski ◽  
Artur Barełkowski ◽  
Mateusz Tympalski
Keyword(s):  
Surface Layer ◽  
High Temperatures ◽  
Induction Heating ◽  
Laboratory Tests ◽  
Hot Forging ◽  
Forging Process ◽  
Induction Heater ◽  
Forged Parts ◽  
Hot Die Forging

Based on tests results, the possibility of using this solution in the technique of industrial hot forging was evaluated. The results of laboratory tests have confirmed that lubrication of metal pieces is sufficient as well as proved it to be effective in reducing decarburization of the surface layer. Research works conducted in an induction heater showed differences in decarburization depending on a substance and concentration of lubricants that were used. These differences become more apparent when observing the surface layer of the forged parts. Results indicate that decarburization may be reduced to a minimum when we use Bonderite product in a concentration of 66% and 50%. Another lubricant, Berulit 913, may also be used. However, due to burning graphite in high temperatures, reduction of decarburization goes only as far as half of the thickness of the decarbonized layer. Condursal has no significant effect; nevertheless, it protects over the induction heating stage.

scholarly journals A comparative analysis of hot and cold flashless forging of a stepped shaft using vertically-parted dies

2021 ◽  
Author(s):  
Tomasz Bulzak ◽  
Janusz Tomczak ◽  
Zbigniew Pater
Keyword(s):  
Comparative Analysis ◽  
Metal Forming ◽  
Effective Strain ◽  
Hot Forging ◽  
Cold Forging ◽  
Geometrical Parameters ◽  
Forging Process ◽  
Stepped Shaft ◽  
One Step ◽  
Hot Forging Process

AbstractFlashless forging is classified as a precise metal forming technology. The main advantages of this technology are the reduction of the flash allowance and the shortening of the manufacturing time by eliminating the flash trimming operation. The article presents the process of one-step forging of a stepped shaft made of aluminum with the use of split dies. The process was carried out in cold and hot metal-forming conditions. The forging process was analyzed numerically using the Simufact Forming 15.0 software. The geometrical parameters of the obtained product were analyzed, and the distribution of effective strain, temperature, and the standardized cracking criterion was determined. The process force parameters were also determined. Numerical tests were verified in real conditions with the use of a specially designed device for forging in vertical split dies. Comparison of hot and cold forging in vertical split dies is presented. The comparative analysis results have demonstrated that the hot forging process has more advantages than the cold forging process. The hot forging process ensures higher accuracy of forged parts.

scholarly journals Case Study of the Effect of Precoating on the Decarburization of the Surface Layer of Forged Parts during the Hot Die Forging Process

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 422
Author(s):  
Paweł Widomski ◽  
Maciej Zwierzchowski ◽  
Artur Barełkowski ◽  
Mateusz Tympalski
Keyword(s):  
Surface Layer ◽  
Induction Heating ◽  
Hot Forging ◽  
Heating Process ◽  
Forging Process ◽  
Die Forging ◽  
Forged Parts ◽  
Third Stage ◽  
Hot Die Forging

This paper aims to evaluate the effect of pre-coating of forged parts on decarburization in the die forging process. The studies consisted of three stages. In the first instance, different coatings were tested under laboratory conditions by heating steel samples to the temperature of 1200 °C for over five minutes to model the preheating conditions of the induction. Next, testing continued in a commercial forging stand where we tested the effects of different coatings on the rods decarburization during the induction heating process, usually performed before forging. Once completed testing, the measurements and observations of the decarbonized layer were made. The third stage involved analysis of the decarburization of the forged parts after forging. The forged parts were made using precoating of pre-forging elements; pieces cut off a metal rod. Based on tests results, the possibility of using this solution in the technique of industrial hot forging was evaluated. The results of laboratory tests have confirmed that lubrication of metal pieces is sufficient, as well as proved it to be effective in reducing decarburization of the surface layer. Research works conducted in an induction heater showed differences in decarburization depending on a substance and concentration of lubricants that were used. These differences become more apparent when observing the surface layer of the forged parts. Results indicate that decarburization may be reduced to a minimum when we use Bonderite product in a concentration of 66% and 50%. Another lubricant, Berulit 913, may also be used. However, due to burning graphite in high temperatures, reduction of decarburization goes only as far as half of the thickness of the decarbonized layer. Condursal has no significant effect; nevertheless, it protects over the induction heating stage.

scholarly journals Investigation of Forging Performance for AA6082

2021 ◽  
Author(s):  
Ozkan Tunc ◽  
Ilyas Kacar ◽  
Fahrettin Ozturk
Keyword(s):  
Hot Forging ◽  
Cold Forging ◽  
Aged Alloy ◽  
Major Drawback ◽  
The Poor ◽  
Design Changes ◽  
Forged Parts ◽  
Aging Conditions ◽  
6082 Aluminum Alloy ◽  
6Xxx Series

Abstract 6XXX series aluminum alloys are generally excellent alternatives to steels for many forged parts in aerospace and automotive industries. In this study, the forging performance of the 6082 aluminum alloy is investigated in order to replace the existing material for forged steel parts. The effect of artificial aging of the alloy on the microstructure and mechanical properties is studied. Optimum aging conditions are determined. Results reveal that AA6082 could be a good replacement for applications where shock and vibrational loads exist. The rod end part currently manufactured from AISI1045 can be replaced by AA6082 without any design changes. The major drawback is that the cold forging of the aged alloy is poor due to its brittle nature and crack initiations. Therefore, warm or hot forging is recommended to overcome the poor forgeability.

scholarly journals Application of Numerical Simulation and Physical Modeling for Verifying a Cold Forging Process for Rotary Sleeves

2021 ◽  
Author(s):  
Tomasz Bulzak ◽  
Grzegorz Winiarski ◽  
Łukasz Wójcik ◽  
Mirosław Szala
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Experimental Tests ◽  
Simulation Software ◽  
Cold Forging ◽  
Work Piece ◽  
Geometrical Parameters ◽  
Forging Process ◽  
Forged Parts ◽  
Element Method

AbstractThis paper presents the modeling of a cold forging process for a rotary sleeve. The process of forging a EN 42CrMo4 steel part was first modeled numerically by the finite element method using simulation software DEFORM 3D ver. 11.0. After that, the developed forging process was verified by experimental tests carried out in laboratory conditions with the use of 1:2 scale tools and a material model of aluminum alloy EN AW-6060. Finite element method (FEM) results demonstrated that rotary sleeves could be formed from tubes by cold forging. Results of the experimental tests showed, however, that the material inside the hole of the work piece might not adhere to the surface of the sizing pin. Distributions of strain and stress during the forging process are determined. Geometrical parameters of forged parts obtained in experimental tests are compliant with the dimensions of forged parts simulated by FEM. In addition, experimental forces of the forging process show a high agreement with the forces obtained in FEM simulations.

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