• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2000.04a
• /
• pp.104-108
• /
• 2000

Drilling Jig is the device according to industrial demand for multi manufacturing products on the growing at alarming rate. In the field of design and making for machine tool working, welding, assembling with jig and fixture for mass production is a specific division. In order to prevent the production defects the optimum design of product, fig and fixture putting in the field is very significant manufacturing method. They require analysis of many kinds of important factors, theory and practice of machine tool operating process and its phenomena, jig & fixture structure, machining condition for tool making tool materials, heat treatment of jig & fixture components, know-how and so on. In this study we designed and constructed a drilling jig of mass production and performed tryout under the Auto CAD, database, and window environment. Especially Part1 of this study is reveals with the analysis of part drawing, jig planning, jig design etc.

• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10a
• /
• pp.968-973
• /
• 1991

Seven axis modular type pneumatic manipulator is composed of electro-pneumatic automation system which contributes to factory automation by performing loading & unloading process successively which is simple routine work of dealing item of machine tool, catapult, assembly machine, welding machine and so on. In this study, we obtained soft and quick movement in a large space and good reliability motion of various function by combining several actuators which perform rotation movement as well as linear movement at the same time. Gripper which apply to rotary sensor transmitted a structure to demanded position. This development item of 5kgf load prevent stick-slip phenomena of stroke end by designing high cushion internal. We develope flexible manipulator which conforms to demand of user by applying multiple sequence program.

• Proceedings of the Korean Society of Marine Engineers Conference
• /
• 2005.11a
• /
• pp.224-225
• /
• 2005

The lightness of components required on marine and shipbuilding industry is requiring high strength of components. In particular, fatigue failure phenomena, which happen in metal, bring on danger in human life and property. Therefore, antifatigue failure technology takes an important part of current industries. In this study, it was investigated about endurance and fatigue crack propagation rate of according to stress ratio of SMAW commonly using for welding structures in present. Fatigue crack propagation rate(da/dN) of low load(R=0.1) was lower than of high load(R=0.6) for piping weld. And in stage I, ${\Delta}$Kth, the threshold stress intensity factor of the weld under heavy load is higher than under small load. Fatigue life shows more improvement in the weld of stress ratio R=0.l than in the weld of stress ratio R=0.6.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.16 no.1
• /
• pp.77-82
• /
• 2017

A computer simulation method is introduced to understand the joining phenomena of PC and CFRP by estimating the temperature of the weld zone. Following the prior or preliminary research, the power range was set between 3 watts and 7 watts, and the scanning speed was set at 500 mm/min and 1,000 mm/min, respectively. Based on the computer simulation, the temperature near the joining boundary was not sufficient at the scanning speed of 1,000 mm/min, regardless of the selected powers. However, the temperature increases above the melting temperature of the selected polymers at the scanning speed of 500 mm/min. The simulation results were compared with actual weld samples to validate its actual use.

• Proceedings of the KWS Conference
• /
• 1999.05a
• /
• pp.241-244
• /
• 1999

The purpose of this study is to examine the characteristics of stress corrosion cracking(SCC) and acoustic emission(AE) signals for the weld HAZ of HT-60 steel under corrosion control in synthetic seawater. Corrosive environment was controlled by potentiostat, and SCC experiment was conducted using a slow strain rate test method at strain rate of 10$^{-5}$ /sec. In order to verify the miroscopic fracture behaviour of the weldment during SCC phenomena, AE test was done simultaneously. Besides, correlationship between mechanical parameters and AE ones was investigated. In case of the parent, reduction of area(ROA) at -0.5V was samller than any other applied voltage such as -0.8V and -1.1V. In addition, reduction of area for the PWHT specimens at -0.8mV was larger than that of the weldment due to the softening effect according to PWHT. In case of the weldment, a lots of events was produced because of the singularities of the weld HAZ compared with the parent.

• Proceedings of the KWS Conference
• /
• 2005.06a
• /
• pp.367-369
• /
• 2005

For the purpose of the optimization or the break through of production processes, it is essential to understand or theoretically interpret dominant mechanisms of the processes, and further more, archive them. and utilize them combining some of them which are needed. Especially in the technology for micro- or nano-scaled objects, adhesion phenomenon is no more negligible, because the adhesion force is proportional to the size of objects meanwhile gravity force is proportional to the third power of it. Author has been working about the mechanisms for micro-assembly processes, which include joining processes and manipulation processes. In the present paper, the strategy and the progress to establish the micro-assembly technology archive are introduced. Some of the mechanisms are introduced with related basic approaches to the adhesion phenomena. Also it will be expressed that our data base project for the surface and interfacial energies is strongly related to these basic approaches.

• Journal of Industrial Technology
• /
• v.1
• /
• pp.9-16
• /
• 1981

In the steel Structural design, buckling is the main factor to determine size, particularly in compression member. Buckling may sometimes occur in the form of wrinkles in thin elements, such as webs, flanges, and other parts that make up a section. This phenomenon is called local buckling. The strength of the steel and the rigidity of the frame are considerably deteriorated by the local buckling. The specimens used for this experiments, H-Shape Steel beams composed by fillet-welding, are dessified classified into two groups, ie one for web test and another for flange fest. The aim of this study is to define the influences by the local bucking on the vesisting forces, deformation and the phenomena of the internal forces in the section, and to collect the basic data for design of steel beams.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.12 no.2
• /
• pp.13-34
• /
• 1975

Analytical solutions for the transient temperature distribution and quasi-static thermal stresses which arise in a thin circular disk of finite radius subjected to an instantaneous point source acting in its interior have been obtained. And the solutions have been extended to the case of a moving heat source with the aid of the Duhamel's superposition integral. The solutions given are in the form of double infinite serieses, and their numerical results have been compared with the experimental temperature histories. It can be found out that the theoretical histories of thermal stresses show a good agreement with the experimental results and the theoretical histories of thermal stresses show a good qualitative agreement with a physical phenomena. The solutions can be applied to the problems such as a flame hardening of the cylindrical machine elements and a circular patch welding or a circular cutting of the structural member.

• Journal of the Korean Society for Precision Engineering
• /
• v.19 no.3
• /
• pp.66-72
• /
• 2002

Electronic Speckle Pattern Interferometry (ESPI) has been recently developed and widely used because it has advantage to be able to measure surface deformations of engineering components and materials in industrial areas with non-contact. The speckle patterns to be formed with interference and scattering phenomena can measure not only out-of-plane but also in-plane deformations, together with the use of digital image equipment to process the informations included in the speckle patterns and to display consequent interferogram on a computer monitor. In this study, the experimental results of a canti-levered plate using ESPI were compared with those obtained from the simple beam theory. The ESPI results of the canti-levered plate analyzed by 4-step phase shifting method are close to the theoretical expectation. Also, out-of-plane displacements of a spot welded cacti-levered plate were measured by ESPI with 4-step phase shifting technique. The phase map of the spot welded cacti-levered plate is quite different from that of the canti-levered plate without spot welding.

• Journal of Welding and Joining
• /
• v.13 no.3
• /
• pp.106-115
• /
• 1995

To know the bonding phenomena of Ti/Cu brazed joint, a characteristic of microstructures in bonding interlayer of vacuum brazed pure Ti to Cu has been studied in the temperature range from 1088 to 1133K for various bonding times using Ag-28wt%Cu filler metal. Also intermediate phases formed in bonded interlayer and behavior of layer growth have been investigated. The obtained results in this study are as follows: 1) Liquid insert metal width at the each brazing temperature was proportional to the square root of brazing time, and it was considered that the liquid insert metal width was controlled by the diffusion rate process of primary .alpha.-Cu formed at the Ti side. 2) Intermediate phases formed near the Ti interface were .betha.-Ti and intermetallic compounds TiCu, Ti$_{2}$Cu, Ti$_{3}$Cu, and TiCu. 3) .betha.-Ti formed in Ti base metal durig brazing transformed to lamellar structure, .alpha.-Ti + Ti$_{2}$Cu. The structure came from the eutectoil decomposition reaction in cooling. And the width of .betha.-Ti layer was proportional to the square root of brazing time, and it was considered that the growth of .betha.-Ti layer was controlled by interdiffusion rate process in .betha.-Ti. 4) The layer growth of TiCu, Ti$_{3}$Cu$_{4}$ and TiCu, phases formed near the Ti interface was linerface was linearly proportional to the brazing time, and it was considered that the layer growth of these phases was controlled by the chemical reaction rate at the interface.