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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Manufacturing Technology Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Manufacturing Technology Engineers
Editor in Chief :
Volume & Issues
Volume 22, Issue 6 - Dec 2013
Volume 22, Issue 5 - Oct 2013
Volume 22, Issue 4 - Aug 2013
Volume 22, Issue 3 - Jun 2013
Volume 22, Issue 3_1spc - Jun 2013
Volume 22, Issue 2 - Apr 2013
Volume 22, Issue 1 - Feb 2013
Selecting the target year
A Study on Failure Diagnosis System for a Hydraulic Pump in Injection Molding Machinery Using Vibration Analysis
Kim, Taehyun ; Jeon, Yongho ; Lee, Moon Gu ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 343~348
DOI : 10.7735/ksmte.2013.22.3.343
In line with the advances in factory automation, various pieces of equipment are now operated in batch processes controlled by computers. However, many kinds of faults can occur in complicated and large systems, which can result in low productivity and economic loss. The reliability and safety of systems have been studied because of the difficulty of determining the severity and location of faults. Therefore, it is necessary to detect and diagnose such faults in order to guarantee the reliability and safety of the equipment. In this paper, a diagnosis method for the ball bearings of a hydraulic pump is applied using a vibration signal for the maintenance of injection molding equipment. The bearings' defects are selected as a main failure mode through a failure mode and effect analysis (FMEA). Usually, there are nonlinear and impulse components of vibration in a ball bearing with faults. For the effective fault diagnosis of a ball bearing, nonlinear diagnostic methods and time-frequency analysis are applied, in addition to the methods currently used, such as power spectrum, time series analysis, and statistical methods. As a result of this study, a failure diagnosis system is provided that is useful even for non-experts. This is a condition-based method that makes it possible to resolve problems in a timely and economical way, in contrast to the prior method, which required regular but wasteful maintenance based on the experience of expensive external experts.
Machine Capability Index Evaluation of Machining Center and Comparative Analysis with Machine Property
Hong, Won-Pyo ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 349~355
DOI : 10.7735/ksmte.2013.22.3.349
Recently, there is an increasing need to produce more precise products with small deviations from defined target values. Machine capability is the ability of a machine tool to produce parts within a tolerance interval. Capability indices are a statistical way of describing how well a product is machined compared to defined target values and tolerances. Today, there is no standardized way to acquire a machine capability value. This paper describes a method for evaluating machine capability indices in machining centers. After the machining of specimens, the straightness, roundness, and positioning accuracy were measured by using CMM (coordinate measuring machine). These measured values and defined tolerances were used to evaluate the machine capability indices. It will be useful for the industry to have standardized ways to choose and calculate machine capability indices.
A Study on the Optimal Design of Mechanical Molding Press for Semiconductor Packaging
Kim, Moon-Ki ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 356~363
DOI : 10.7735/ksmte.2013.22.3.356
Mechanical molding press which is used for transformation process during semiconductor manufacturing process has structural deformations by pressure. If these deformations have over limit range, life of the press itself can be reduced and it will be exerted on a bad effect for quality of the semiconductor. In this research, the main plates and links of a press are analyzed in relation to the structural deformations caused by pressure excluding thermal deformations. After modifying the modeling, the analysis is performed again to determine optimal design of the press, and this design is introduced to ensure that most of the stresses on the main plates are within safe allowable limits. As a result, an optimal design method for the structure is investigated to produce the desired pressure even when the size of the main structure is minimized.
Steady State Performance Analysis of the Multi-mode Power Transmission Systems Equipped on Passenger Car
Lim, Won-Sik ; Park, Yun-Kyoung ; Park, Sung-Cheon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 364~371
DOI : 10.7735/ksmte.2013.22.3.364
Because of the increases in international oil prices and the level of global warming, the automotive industry has much interest in developing green cars with high fuel efficiencies. In addition, researchers in Korea are actively responding to high oil prices and
emission regulations in many ways. One example is, the multi-mode hybrid system, which is being studied to improve its performance. Because a multi-mode hybrid system is able to overcome the weaknesses of a system that uses simple planetary gears, excellent fuel efficiency and driving performances are the key features of the system. This paper analyzes the driving performance of the power-train system of GM-2MT70, which consists of one engine, two electric motors, one simple planetary gear, one double planetary gear, two clutches, and two brakes. The driving performance of the system's steady state is analyzed using performance modeling. The dynamic performance is analyzed using Matlab Simulink.
Change of Mechanical Properties of Clad Steel According to the Welding Process Design
Lee, Jung-Hyun ; Park, Jaw-Won ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 372~379
DOI : 10.7735/ksmte.2013.22.3.372
In this study, we investigated the traits of the clad metals used in hot-rolled clad steel plates. We examined the sensitization and mechanical properties of STS 316 steel plate and carbon steel (A516) under the specific circumstances of post heat treatment and whether a weld was multilayered and thick or repeated because of repairs. The test conditions were as follows. The clad steel plates were butt-welded using FCAW/SAW, and the heat treatment was conducted at
, for 80, 160, 320, 640, or 1280 min. The change in the corrosion resistance was evaluated in these specimens. In the case of the carbon steel (A516), as the heat treatment time increased, the annealing effect caused the tensile strength to decrease. The micro- hardness gradually increased and then decreased after 640 min. The elongation and contraction of the area increased gradually. An oxalic acid etch test and EPR test on STS316, a clad metal, showed a STEP structure and no sensitization. From the test results for the multi-layered and repair welds, it could be concluded that there is no effect on the corrosion resistance of clad metals. In summary, the purpose of this study was to suggest some considerations when developing on-site techniques and evaluate the sensitization of stainless steels.
Evaluation of Thermal Characteristics for a Feeding Axis of Machine Tools Using Finite Element Analysis
Lee, Chang Hoon ; Choi, Jin Woo ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 380~387
DOI : 10.7735/ksmte.2013.22.3.380
In this study, two finite element (FE) models were developed to evaluate the thermal characteristics of a feeding axis of a CNC lathe. One was used for analysis of heat transfer to identify the temperature distribution of the feeding axis and then, the other was used for analysis of thermal deformation to evaluate its structural behavior based on the temperature distribution. The FE models were based on the test standard for the axial thermal displacement. The feeding velocity was composed of three steps: the ascending, constant, and descending velocities. Therefore, the heat generation and convection coefficient were calculated for each velocity and applied to the thermal FE model. The convection coefficient for the ball screw rotation was based on an experimental equation. The result of the analytical thermal displacement was compared with that of the experimental displacement to verify the finite element models.
Dynamic Characteristics of CFRP Structure Member According to Change the Stacking Angle and Shape
Yeo, In-Goo ; Choi, Ju-Ho ; Yang, In-Young ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 388~393
DOI : 10.7735/ksmte.2013.22.3.388
Carbon fiber reinforced plastic (CFRP) has many desirable qualities, including being lightweight and very strong. These characteristics have led to its use in applications ranging from small consumer products to vehicles. Circular and square CFRP members were fabricated using 8ply unidirectional prepreg sheets stacked at different angles (
coincides with the axis of the member). Based on the collapse characteristics of a CFRP circular member, the collapse characteristics and energy absorption capability were analyzed. Impact collapse tests were carried out for each section member. In this study, the impact energies at crossheads speeds of 5.52 m/s, 5.14 m/s and 4.57 m/s were 611.52 J, 529.2 J and 419.44 J (circular member) 2.16 m/s, 1.85 m/s and 1.67 m/s are 372.4 J, 274.4 J and 223.44 J (square member). The purpose is to experimentally examine the absorption behavior and evaluation the strength in relation to changes in the stacking configuration when the CFRP circular members with different stacking configurations were exposed to various impact velocities. In addition, the dynamic characteristics were considered.
Rockwell Hardness Modeling Using Volumetric Variable
Chin, Do-Hun ; Oh, Sang-Rok ; Yoon, Moon-Chul ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 394~401
DOI : 10.7735/ksmte.2013.22.3.394
A new Rockwell hardness (HRC) model using a volumetric parameter by a least square and fractal interpolation method is suggested. The results are also investigated in comparison to real measured hardness data. For this purpose, the measurement of an indented volume is performed using a confocal laser scanning microscope (CLSM), and the captured height encoded image (HEI) is used as an original surface for the calculation of the indented volume. After configuring the surface, the constructed volume is calculated and used as an independent variable for HRC hardness modeling. The hardness model is established using an experimental modeling technique involving a least square algorithm and fractal interpolating model, and this suggested model can be used to reliably predict the Rockwell hardness. These techniques can also be applied to the modeling of the Brinnell and Vickers hardnesses using a volumetric variable.
A study on the Flat Zone Length of Workpiece at Flexible Disk Grinder Cutting Process Measurement and Prediction using Image Processing
Shin, Kwan Soo ; Roh, Dae Ho ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 402~407
DOI : 10.7735/ksmte.2013.22.3.402
In this paper, the image processing for flexible disk grinding and the effect of the grinding conditions on the flat zone length of a workpiece are investigated, with the purpose of automating the grinding process. To accomplish this, three issues should be carefully studied. The first is finding the relationship between the flat zone length and the grinding conditions such as the cutting speed and feeding speed. The second is developing a neural network algorithm to predict the flat zone. The third is developing an image processing algorithm to measure the flat zone length of a workpiece. Slope analysis is used to determine straight and curved sections during the image processing. For verification, the estimated length and the length from the image processing are compared with the length measured by a projector. There is a minimum difference of 1.7% between the predicted and measured values. The results of this paper will be useful in compiling a database for process automation.
Improvement of Form Accuracy of Micro-Features on Thin, Large-area Plate using Fast Depth Adjustment in Micro-grooving
Kang, Dong Bae ; Son, Seong Min ; Lee, Hyo Ryeol ; Ahn, Jung Hwan ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 408~413
DOI : 10.7735/ksmte.2013.22.3.408
Micro-features such as grooves and lenses, which perform optical functions in flat displays, should be manufactured with a good form accuracy because this is directly related to their optical performance. As the size of the display increases, it is very difficult to maintain a high relative accuracy because of the inherent geometric errors such as the waviness of a large-area plate. In this paper, the optical effect of these geometric errors is investigated, and surface-referenced micro-grooving to measure and compensate for such geometric errors on line is proposed to improve the form accuracy of the micro-grooves. A PZT-based fast depth adjustment servo system is implemented in the tool holder to maintain a uniform groove depth in reference to the wavy surface. Through experiments, the proposed method is shown to be an efficient way to produce high-quality micro- grooves on a wavy die surface.
Reliability Evaluation on Pultrusion Composite Sandwich Panel
Lee, Haksung ; Kim, Eunsung ; Oh, Jeha ; Kim, Dongki ; Lee, Juyoung ; Kang, Shinjae ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 414~420
DOI : 10.7735/ksmte.2013.22.3.414
Research on decreasing the weight of composite sandwich panels is in progress. This paper reports the experimental results for the mechanical behavior of a composite sandwich panel. The skins of sandwich panels were made of glass fiber sheets and plywood matrix composites. Their interior layers consisted of glass fiber pultrusion pipes and gold foam. Experimental tests were performed to obtain the mechanical properties and complex mechanical behavior. Before fatigue tests, tensile tests and 3-point bending tests were carried out to obtain the optimal design and determine their strength and failure mechanisms in the flat-wise position. After the static test, a fatigue test were conducted at a load frequency of 5 Hz, stress ratio (R) of 0.1, and endurance limit for the S-N curve. It showed that the failure modes were related to both the core design and skin failure.
A Method of Effective Vibration Reduction for Positioning Systems Undergoing Frequent Short-distance Movement
Hong, Seong-Wook ; Bae, Gyu-Hyun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 421~428
DOI : 10.7735/ksmte.2013.22.3.421
The current vibration reduction methods for positioning systems lead to either complicated motion or the need for additional hardware when the positioning systems carry out frequent short-distance movements. This paper proposes a simple yet efficient vibration reduction method for positioning systems subjected to frequent short-distance movements. The essence of the proposed method is the trapezoidal or triangular velocity profiles, whose acceleration/deceleration rates are designed to be related to the natural frequency of concern. The combined use of the proposed method and the input shaping method is also proposed for the possible application to multi-mode systems. Experiments are performed to validate the proposed method. The simulation and experiments prove that the proposed method is of great use for residual vibration reduction in positioning systems subjected to frequent short-distance movement.
A Study on Aspheric Optics European LED Streetlights Type for the Prevention of Light Pollution
Lee, Shi-Woo ; Lee, Chang-Soo ; Hyun, Dong-Hoon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 429~436
DOI : 10.7735/ksmte.2013.22.3.429
In this study, we researched a pendant-type aspherical optical system, which could be applied to street lighting and security lighting in Europe. The goal of this research was eco-friendly artificial lighting that could be used for the one-to-one replacement of ordinary lighting. LED lighting was miniaturized by using one COB LED Module and one aspherical optical system, which could control the luminosity of the LED. Through the aspherical optical system, the light distribution angle could be controlled in a range of
for the X-axis and
for the Y-axis. This means that this optical system is appropriate for catenary-type lighting, which is widely used in Europe on both narrow and broad roads. The performance was determined using a lighting simulation program. This lighting system simulation showed that road rates M4 and M5 could be satisfied, with the condition of a 13-m height and 50-m distance (U0 and TI). The simulation program estimated that light pollution, which disturbs sleep, could beeliminated in the European streetlight case. Determining methods for the light distribution control, performance, and optimal lighting setup conditions is very important to prevent light pollution. Moreover, the initial step of developing the lighting system design and post management will require an effort with much analysis.
Prediction and Measurement of Cutting Force in Side-Milling
Lee, Chang-Ho ; Yang, Min-Yang ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 437~446
DOI : 10.7735/ksmte.2013.22.3.437
There have been numerous studies on end milling processes. However, these have been restricted to the application of tools for special cutting purposes. A side milling cutter can handle long, deep, and open slots in a more efficient manner, and it provides the best stability and productivity for this type of milling. In this paper, a method to predict the cutting forces in side milling is described, and simulated cutting forces are compared with those obtained by cutting experiments. In particular, the side milling process easily generates relative motion between the tools and the workpiece because it produces intermittent cutting forces that cause vibrations over a wide frequency range. Therefore, the application of a dynamic cutting model instead of a static cutting model is appropriate to forecast the cutting forces more accurately.
Development of a Shock Absorber with an Orifice Sensitive to Velocity
Moon, Sahyun ; Kim, Ock Hyun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 447~451
DOI : 10.7735/ksmte.2013.22.3.447
In this study, a shock absorber whose orifice area changes according to the oil pressure inside the absorber is developed. The orifice widens and narrows when the oil pressure is high and low, respectively; thus, the orifice area changes according to the oil pressure, in other words, according to the extension/compression velocity. It is well known that the damping force can be expressed as
. For fluid film damping, the force is proportional to velocity, i.e.,
, and for orifice damping, it is proportional to the square of velocity, i.e.,
. The shock absorber proposed in this paper can exhibit different relationships between the damping force and velocity because the orifice area changes according to the induced oil pressure. The motivation of this study is to develop a method for designing a shock absorber with desired values of C and
which is not just 1 or 2. Theoretical and experimental studies have been conducted to verify the damping characteristics of the shock absorber. The effect of some major design parameters on damping characteristics has been also examined to relate the design parameters to the damping characteristics.
Development of An Inspection Method for Defect Detection on the Surface of Automotive Parts
Park, Hong-Seok ; Tuladhar, Upendra Mani ; Shin, Seung-Cheol ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 452~458
DOI : 10.7735/ksmte.2013.22.3.452
Over the past several years, many studies have been carried out in the field of 3D data inspection systems. Several attempts have been made to improve the quality of manufactured parts. The introduction of laser sensors for inspection has made it possible to acquire data at a remarkably high speed. In this paper, a robust inspection technique for detecting defects in 3D pressed parts using laser-scanned data is proposed. Point cloud data are segmented for the extraction of features. These segmented features are used for shape matching during the localization process. An iterative closest point (ICP) algorithm is used for the localization of the scanned model and CAD model. To achieve a higher accuracy rate, the ICP algorithm is modified and then used for matching. To enhance the speed of the matching process, aKd-tree algorithm is used. Then, the deviation of the scanned points from the CAD model is computed.
Development of Micro Mixing Device with Using Ultrasonic Wave
Jeon, Yongho ; Choi, Byung-Joo ; Kang, Seung-Joon ; Kim, Dong-Kwon ; Kim, Hyun-Jung ; Lee, Moon Gu ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 459~464
DOI : 10.7735/ksmte.2013.22.3.459
The purpose of a micro-mixing device is to enhance the mixing by increasing the diffusion effect between different types of flows. There have been many attempts to actively or passively increase mixing. However, those studies were limited to lab-scale experiments because the production of devices requires a series of processes, time, cost, and the mixing quality itself. For this reason, this study attempted to develop a quick and simple process for micro-mixing device fabrication by using conventional machining and bonding processes and applying ultrasonic waves from the outside of the mixing device. The mixing quality was quantified by using the mixing index, and the results showed that the proposed system increases the mixing from ~33% to ~10% with respect to the flow rates.
Methodology for Simulation of Trochoid Pump
Kim, Myung Sik ; Chung, Won Jee ; Jeong, Seung Won ; Jeon, Ju Yeal ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 465~471
DOI : 10.7735/ksmte.2013.22.3.465
Flow rate control is the uppermost concern for a trochoid hydraulic pump. Cavitation within the flow field of the pump has the greatest effect on the flow control during high-speed pump rotation of approximately 3500~4000 RPM. In this paper, based on AMESim
and Solid Works
, we will present a method to simulate cavitation by analyzing the control factors of a trochoid pump, including the hydraulic pressure change at the outlet, flow rate based on the rotation speed of the inner rotor, leakage through the gap between the outer and inner rotors, and discharging angle of the outlet. The proposed methodology of the [cavitation simulation will enable field engineers to more easily design trochoid pumps, and will allow more concrete control over the flow rate of the pump by realizing an analysis model similar to the actual product model.
Development of Film Fixing System for Improving Overlap Defects in the Film Insert Injection Molding Process
Kim, Jung-Ho ; Mun, Ji-Hun ; Park, Hong-Seok ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 472~479
DOI : 10.7735/ksmte.2013.22.3.472
We carried out research into an environmentally friendly injection molding process that involves filling the mold with polymer after thin films are fixed into the cavity, without the coating, plating process. Film insert injection molding is a new technique in which molten plastic resin is injected into the cavity after films are precisely attached to the side of the mold wall. In the film insert injection molding process, the insert film is moved by the flow of the molten plastic resin. Overlap defects cause a decline in the productivity and the quality of the manufactured goods. To reduce overlap defects, new injection mold parts are proposed to produce automotive exterior parts using thin films. It is suggested that the best possible method would be to fix the thin films to one side of the mold wall, and develop interior pins to fix the films in the mold. Based on this new pin fixing system, the problem of the film being moved by the flow of the molten resin was improved.
A Study on Aspheric Optics Research for Improving the Luminous Efficiency of the LED MR16
Yoo, Sook-Chul ; Yoo, Kyung-Sun ; Hyeon, Dong-Hun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 3, 2013, Pages 480~487
DOI : 10.7735/ksmte.2013.22.3.480
In this study, we researched the LED source MR16,which maintains the strong points of an ordinary MR16 while compensating for its weak points. The optical system composition of the LED MR16 includes four aspherical lens per sheet and a patterned reflector. The aspherical optical system and reflector were designed using optical software, and the performance was estimated using a lighting simulation program. Finally, a prototype was manufactured after analyzing the simulation data, and the reliability of the simulation results was estimated using a comparative analysis of the designed data and measured data.