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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society of Manufacturing Process Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Manufacturing Process Engineers
Editor in Chief :
Volume & Issues
Volume 13, Issue 6 - Dec 2014
Volume 13, Issue 5 - Oct 2014
Volume 13, Issue 4 - Aug 2014
Volume 13, Issue 3 - Jun 2014
Volume 13, Issue 2 - Apr 2014
Volume 13, Issue 1 - Feb 2014
Selecting the target year
Structural analysis of a planetary gear carrier in the slewing reducer for tower crane
Cho, Seung-Je ; Han, Jeong-Woo ; Park, Young-Jun ; Lee, Geun-Ho ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 1~7
DOI : 10.14775/ksmpe.2014.13.5.001
In this paper the structural analysis of a planet carrier was carried out for the design optimization of a slewing reducer used in tower cranes. The stress changes of the planet carrier according to the tolerance of interference fit were investigated, and the strength was evaluated on the basis of the stress level. The analysis results showed that the tolerance of interference fit have an important influence on the stress level of the planet carrier. To guarantee the static safety of carrier, the tolerances of carrier pinhole and planet pin as well as loading level exerted on the planet carrier should be determined considered correctly.
Effects of Bearing Characteristic on the Gear Load Distribution in the Slewing Reducer for Excavator
Kim, Jeong-Gil ; Park, Young-Jun ; Lee, Geun-Ho ; Kim, Jae-Hoon ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 8~14
DOI : 10.14775/ksmpe.2014.13.5.008
A slewing reducer consists of two planetary gearsets which require a good load distribution over the gear tooth flank for enhanced durability. This work investigates how the bearing characteristics influence the load distribution over the gear tooth flank. A complete system model is developed to analyze a slewing reducer, including the non-linear mesh stiffness of the gears and the non-linear stiffness of bearings. The results indicate that the type, arrangement and preload of the output shaft bearings greatly influence the gear mesh misalignment, contact pattern, face load factor, gear safety factor and lifetimes of the parts.
A Study on Optimization of Tooth Micro-geometry for Wind Turbine High Speed Stage Helical Gear Pair
Cho, Sungmin ; Lee, Do-Young ; Kim, Laesung ; Cho, Sangpil ; Lyu, Sung-Ki ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 15~20
DOI : 10.14775/ksmpe.2014.13.5.015
The wind industry grew in the first decade of the 21st century at rates consistently above 20% a year. For wind turbine, gearbox failure can be extremely costly in terms of repair costs, replacement parts, and in lost power production due to downtime. In this paper, gear tooth micro-modification for the high speed stage was used to compensate for the deformation of the teeth due to load and to ensure a proper meshing to achieve an optimized tooth contact pattern. The gearbox was firstly modeled in a software, and then the various combined tooth modification were presented, and the prediction of transmission under the loaded torque for the helical gear pair was investigated, the normal load distribution and root stress were also obtained and compared before and after tooth modification under one torque. The simulation results showed that the transmission error and normal load distribution under the load can be minimized by the appropriate tooth modification. It is a good approach where the simulated result is used to improve the design before the prototype is available for the test.
Study on Bearing Life Calculation for Wind Turbine Gearbox
Liang, Long-jun ; Choi, Chang ; Zhang, Qi ; Xu, Zhe-Zhu ; Lyu, Sung-Ki ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 21~27
DOI : 10.14775/ksmpe.2014.13.5.021
Currently, wind power has become a major research field in the area of sustainable development. As one important component of a wind turbine transmission system, most instances of downtime due to a gearbox failure are caused by bearing failures. Gearboxes for wind turbines must have the highest levels of reliability over a period of approximately 20 years, withstanding high dynamic loads. At the same time, a lightweight design and cost minimization efforts are required. These demands can only be met with a well-thought-out design, high-quality materials, a high production quality and proper maintenance. In order to design a reliable and lightweight gearbox, it is necessary to analyze methods pertaining to the bearing rating lifetimes of the standard and of different companies, also including calculation methods for modification factors. This can determine the influence of the bearing lifetime.
Strength and Durability Analysis of the Double Planetary Gears
Han, Sung Gil ; Shin, Yoo-In ; Yoon, Chan Heon ; Song, Chul Ki ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 28~34
DOI : 10.14775/ksmpe.2014.13.5.028
A planetary gear train is more compact and endures greater amounts of transmission power compared to other gear systems. Although planetary gear systems operate in small volumes, they are capable of very high efficiency due to the compact combination of their gears in the planetary gear system. They also have outstanding efficiency of only 3% for power transmission, tantamount to the power loss that occurs in each of the shift stages. Given these advantages, planetary gear systems are used in the driving systems of, which are widely used in automobile transmissions, machine tools, semiconductor equipment, and in other areas in industrial fields. Current structural equipment requires higher efficiency and greater torque levels. According to these needs, we have designed a complex planetary gear system which creates higher levels of torque. In this paper, an evaluation of strength designs for the proposed planetary gear system was conducted to ensure the stability of the gear. In addition, a durability analysis based on Miner`s rule was performed using RS B 0095 device.
Lubrication effect of slider bearing with wavy surface
Wang, Il-Gun ; Chin, Do-Hun ; Yoon, Moon-Chul ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 35~42
DOI : 10.14775/ksmpe.2014.13.5.035
The influence of sine wave striated surface roughness on load carrying capacity of a bearing is studied for thin film effect of slider bearing. A Reynolds equation appropriate for slider bearing is used in this paper for analysis and it is discussed using finite difference method of central difference scheme. For a slider bearing with sine wave simple roughness form, several parameters such as pressure, load capacity and shear stress of the bearing can be obtained and also this results can be stored in sequential data file for latter analysis. After all, their distribution can be displayed and analyzed easily by using the matlab GUI technique. The parameters such as amplitude, number of waviness and slope of the surface are used for discussing the load carrying capacity of the rectangular bearing. The results reported in this paper should be applied to the other slider bearing such as rectangular or round embossed surface of slider bearing.
A Study on Simulation of an Water Cooling Intercooler for a Small Marine Diesel Engine
Yang, Young-Joon ; Sim, Han-Sub ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 43~49
DOI : 10.14775/ksmpe.2014.13.5.043
This study was carried out to improve the design of an intercooler for a small marine diesel engine. Diesel engines for small marine ships have mainly been developed by changing the structure of the vehicle engine. Sea water was most commonly used in the intercooler of small marine diesel engines to cool the hot air compressed by the turbocharger. In this study, the intercooler is modeled and simulated using STAR-CCM+ in order to find optimal data for the design of an intercooler. In the results, the temperature differences between the data from a numerical analysis and experimental data were
in the hot air outlet and
in the cooling water outlet. Therefore, it was confirmed that both analysis and experimental results need to be considered when designing an intercooler. A closer degree of similarity in the two datasets can improve the confidence in the design of these intercoolers.
Determination and Verification of Flow Stress of Low-alloy Steel Using Cutting Test
Ahn, Kwang-Woo ; Kim, Dong-Hoo ; Kim, Tae-Ho ; Jeon, Eon-Chan ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 50~56
DOI : 10.14775/ksmpe.2014.13.5.050
A technique based on the finite element method (FEM) is used in the simulation of metal cutting process. This offers the advantages of the prediction of the cutting force, the stresses, the temperature, the tool wear, and optimization of the cutting condition, the tool shape and the residual stress of the surface. However, the accuracy and reliability of prediction depend on the flow stress of the workpiece. There are various models which describe the relationship between the flow stress and the strain. The Johnson-Cook model is a well-known material model capable of doing this. Low-alloy steel is developed for a dry storage container for used nuclear fuel. Related to this, a process analysis of the plastic machining capability is necessary. For a plastic processing analysis of machining or forging, there are five parameters that must be input into the Johnson-Cook model in this paper. These are (1) the determination of the strain-hardening modulus and the strain hardening exponent through a room-temperature tensile test, (2) the determination of the thermal softening exponent through a high-temperature tensile test, (3) the determination of the cutting forces through an orthogonal cutting test at various cutting speeds, (4) the determination of the strain-rate hardening modulus comparing the orthogonal cutting test results with FEM results. (5) Finally, to validate the Johnson-Cook material parameters, a comparison of the room-temperature tensile test result with a quasi-static simulation using LS-Dyna is necessary.
Design and Performance Test of High-speed Swivel Tool Head
Kim, In-Hwan ; Koo, Ja-Ham ; Hur, Nam-Soo ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 57~63
DOI : 10.14775/ksmpe.2014.13.5.057
At present, a high-speed swivel tool head of a small size is required to improve the productivity of CNC automatic lathes. Hence, there is growing interest in shorter machining times with higher cutting speeds. However, an increase in the rotation speed of a swivel tool head also has adverse effects, such as vibration and noise caused by the swivel tool head system. In this work, the fatigue life and contact pressure of a swivel tool head bearing system driven by gears were calculated. Based on the calculated results, a prototype swivel tool head was manufactured and its static and dynamic characteristics, i.e., the vibration, noise and precision, were measured using a reliability testing device which allows the application of cutting force to the end of the swivel tool head.
Plating hardness and its effect to the form accuracy in shaping of corner cube on cu-plated steel plate using a single diamond tool
Lee, J.Y. ; Kim, C.H. ; Sea, C.W. ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 64~69
DOI : 10.14775/ksmpe.2014.13.5.064
This article presents machining experiments to assess the relationship between the profile accuracy and the workpiece hardness using a natural diamond tool on an ultra-precision diamond turning machine. The study is intended to secure a corner cube prism pattern for reflective film capable of high-quality outcomes. The optical performance levels and edge images of corner cubes having various hardness levels of the copper-coated layer on a carbon steel plate are analyzed. The hardness of the workpiece has a considerable effect on the profile accuracy. The higher the hardness of the workpiece, the better the profile accuracy and the worse the edge wear of the diamond tool.
Design of Neodymium Permanent Magnetic Core using FEM
Hur, Kwan-Do ; Ye, Sang-Don ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 70~75
DOI : 10.14775/ksmpe.2014.13.5.070
Permanent magnets have recently been considered as device that can be used to control the behavior of mechanical systems. Neodymium magnets, a type of permanent magnet, have been used in numerous mechanical devices. These are permanent magnets made from an alloy of neodymium, iron, and boron to form the Nd2Fe14B tetragonal crystalline structure. The magnetic selection, magnet core design and mechanical errors of the magnetic component can affect the performance of the magnetic force. In this study, the coercive force, residual induction, and the dimensions of the design parameters of the magnet core are optimized. The design parameters of magnet core are defined as the gap between the magnet and the core, the upper contact radius, and the lower thickness of the core. The force exercised on a permanent magnet in a non-uniform field is dependent on the magnetization orientation of the magnet. Non-uniformity of the polarization direction of the magnetic has been assumed to be caused by the angular error in the polarization direction. The variation in the magnetic performance is considered according to the center distance, the tilt of the magnetic components, and the polarization direction. The finite element method is used to analyze the magnetic force of an optimized cylindrical magnet.
Determination of Efficient Superfinishing Conditions for Mirror Surface Finishing of Engineering Ceramics
Kim, Sang-Kyu ; Cho, Young-Tae ; Jung, Yoon-Gyo ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 76~81
DOI : 10.14775/ksmpe.2014.13.5.076
The Engineering ceramics have some excellent properties as materials for modern mechanical and electrical components. It is, however, not easy to polish them efficiently because they are strong and hard. This study is carried out to obtain a mirror surface on engineering ceramics by surperfinishing with high efficiency. To achieve this, we conducted a series of polishing experiments using representative engineering ceramics, such as
, using diamond abrasive film from the perspective of oscillations peed, the rotational speed of the workpiece, contact roller hardness, contact pressure and feed rate. Furthermore, the polishing efficiency and characteristics for engineering ceramics are discussed on the basis of optimal polishing time and surface roughness. Our results confirmed that efficient superfinishing conditions and polishing characteristics of engineering ceramics can be determined.
Fireproof Performance Study of ICT Fire Damper by Using Experimentalmethode
Hur, Nam-Soo ; Kim, In-Whan ; Jang, Sung Cheol ; Kim, Jae-Woong ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 82~89
DOI : 10.14775/ksmpe.2014.13.5.082
In this paper, fire resistance test was carried out to obtain class H-120 thermal insulation of fire dampers according to a hydrocarbon fire conditions. Specimens were fabricated three different types according to the change of the insulation system applied to damper blade and coaming which were measured surface temperature by performing the fire resistance test. As a test result, specimen-1, 2 of an uninsulated damper blade were exceeded thermal insulation acceptance criteria at 21 minutes, 46 minutes respectively, but specimen-3 of an insulated damper blade was satisfied thermal insulation acceptance criteria during 120 minutes. The test results showed that the insulation of the damper blade was an important factor in the fireproof performance of fire dampers concerning the coaming length minimum 500 mm on the unexposed side as specified test standard.
Dynamics Modeling and Control of a Delta High-speed Parallel Robot
Kim, Han Sung ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 90~97
DOI : 10.14775/ksmpe.2014.13.5.090
This paper presents a simplified dynamics model, dynamics simulations, and computed torque control experiments of the Delta high-speed parallel robot. Using the typical Newton-Euler method, a simplified but accurate dynamics model with practical assumptions is derived. Accuracy and fast calculations of the dynamics are essential in the computed torque control for high-speed applications. It was found that the simplified dynamics equation is in very god agreement with the ADAMS model, and the calculation time of the inverse kinematics and inverse dynamics is about 0.04 msec. From the dynamics simulations, the cycle trajectory along the y-axis requires less peak motor torque and a lower angular velocity and less power than that along the x-axis. The computed torque control scheme can reduce the position error by half as compared to a PD control scheme. Finally, the developed Delta parallel robot prototype, half the size of the ABB Flexpicker robot, can achieve a cycle time of 0.43 sec with a 1.0kg payload.
Evaluation of Plant Growth according to the Wavelength Characteristics of the LED Light Source
Hwang, Jong-Dae ; Ko, Dong-Su ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 98~106
DOI : 10.14775/ksmpe.2014.13.5.098
This study was carried out to evaluate the plant growth rate according to the wavelength characteristics of LED light sources. In order to achieve this, red, green, blue and white LEDs were arrayed in a rectangle array consisting of LED modules which can be combined with each other.. This can facilitate the selection of the optimal characteristics of the light from monochromatic red, green, blue and white LEDs or mixed LEDs for plant growth. Experiments to evaluate the growth rate according to the wavelength characteristics of the LEDs with several plants, in this case ice plants, lettuce, barley, broccoli and chives, were performed.
A Study on the Static/Dynamic Stability and the Fatigue Damages for the Worm Gear in the B-Axis Rotary Table of a Mill Turret
Kim, Chae-Sil ; Kang, Seung-Hee ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 107~115
DOI : 10.14775/ksmpe.2014.13.5.107
Highly functional mill turrets have been developed and continuously improved to shorten the manufacturing time and enable multiple uses. Among these, a mill turret with B-axis rotary table was developed. The B-axis rotary table should be evaluated for structural integrity. Moreover, its worm and worm gear for transmitting power should be able to endure fatigue damage. Therefore, this article presents a structural analysis of this type of B-axis rotary table and confirms its static stability by comparing the stress results to the allowable stress levels. Next, the dynamic stability of the rotary table was investigated via a mode analysis and a harmonic analysis in a range determined by the results of a modal analysis. Finally, a worm gear set, the main part that drives the rotary table, is analyzed for fatigue and to estimate its lifetime. The results of the fatigue analysis allowed a prediction of the life of the worm gear set. The analytical results show that the B-axis rotary table has good structural integrity.
An Analysis on Durability Improvement of Twist Run Exercise Equipment
Han, Moon Sik ; Cho, Jae Ung ;
Journal of the Korean Society of Manufacturing Process Engineers, volume 13, issue 5, 2014, Pages 116~122
DOI : 10.14775/ksmpe.2014.13.5.116
In this study, 2 kinds of twist run models as exercise equipments are compared by durability analyses of fatigue and vibration. Maximum equivalent stresses are shown as 3.3 MPa and 16.6 MPa at the parts of stress concentrations at models 1 and 2. As the values becomes much lower than yield stress of this models, these models are shown to be safe designs. Model 1 becomes stronger than model 2 at natural frequency analysis. Fatigue lives become lowest at four axis parts and one axis part respectively in cases of models 1 and 2. Maximum damage probability at fatigue is shown to be 2.4% near the average stress of 0 in case of model 1 but this probability becomes 0.6 % in case of model 2. Model 1 has the maximum damage possibility 4 times more than model 2 at these states. As the result of this study is applied by the design of twist run, the prevention on fatigue damage and the durability are predicted.