• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2003년도 추계학술대회 논문집
• /
• pp.64-69
• /
• 2003

This paper describes a study on the tearing damage of the ship's bottom plating during a grounding. It has been known widely that difference scaling laws are applied for bodies undergoing simultaneously plastic flow and crack propagation in the deformation of the plate tearing. Especially, the basic scaling law is not followed for the fracture. In this study plate cutting experiments for the geometrically similar models have been performed in order to verify the problem. From the experimental results, it has been observed that the cutting forces and energy for the larger models are significantly lower than those of the smaller models the damage become large. A simplified analytical method for the estimation of tearing is proposed based on the experiments and it has been observed that the results of the present formula are correlated very well with the experiments

• 한국정밀공학회지
• /
• 제17권7호
• /
• pp.147-155
• /
• 2000

To reduce the noise from wood cutting saw at the saw mill(lumber mill) or a construction area, some multi-layer sandwich saw blades which a aluminum or copper plate was inserted between the two steel plates were developed and were tested of the wood cutting noise level at various test places. From the research, it was found that the multi-layer saw blade with copper or aluminum plate between steel plates and spot welded 60 points could reduce the wood cutting sound level about 8.3 dB(97.031 dB - 88.743 dB) at indoor test and 3.8 dB(84.805 - 81.638 dB) at field test.

• 한국해양공학회지
• /
• 제18권1호
• /
• pp.41-46
• /
• 2004

This paper describes a study on the tearing damage of a ship's bottom plating, during a grounding. It is widely known that different scaling laws are applied for bodies undergoing simultaneous plastic flow and crack propagation in the deformation of plate tearing. Specifically, the basic scaling law is not followed for the fracture. In this study, in order to verify the problem, plate cutting experiments for geometrically similar models have been performed. From the experimental results, it has been observed that the cutting forces and energy for the larger models are significantly lower than those of the smaller models. A simplified analytical method for the estimation of tearing is proposed, based on the experiments. It has been observed that the results of the present formula are highly correlated with the experiments.

• 화약ㆍ발파
• /
• 제37권4호
• /
• pp.17-25
• /
• 2019

도폭선과 수평분리판을 이용한 현장타설 말뚝 두부를 제거하는 방법을 제안하였다. 무근 콘크리트 블록을 제작하였고, 콘크리트 블록 발파실험을 통하여 말뚝 두부 절단에 필요한 도폭선 약량과 최소저항선을 확인하였다. AUTODYN 2D를 이용하여 두부 절단 후 콘크리트 블록의 손상 정도를 확인하였다. 실험결과 10g/m 도폭선과 수평분리판을 이용한 콘크리트 블록 절단을 확인하였고, 수평분리판을 사용하여 블록의 방향성 절단과 도폭선에 의한 블록 손상이 저감됨을 확인하였다.

• 소성∙가공
• /
• 제17권2호
• /
• pp.107-112
• /
• 2008

In order to investigate the residual stress evolution during the leveling process of hot rolled high strength coils for cold forming, the in-plane residual stress of plate sampled at SPM, rough leveler and finish leveler were measured by cutting method. Residual stress was localized near the edge of plate. As the thickness of plate was increased, the size of residual stress region was expanded. The gradient of residual stress within the plate was reduced during the leveling process. But the residual stress itself was not removed completely within the ranges of tested conditions. The exact camber of cut plate was able to be predicted by the measurement of residual stress distribution after leveling of the plate.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2007년도 추계학술대회 논문집
• /
• pp.112-115
• /
• 2007

In order to investigate the residual stress evolution during the leveling process of hot rolled high strength coils for cold forming, the in-plane residual stress of plate sampled at SPM, rough leveler and finish leveler were measured by cutting method. Residual stress was localized near the edge of plate. As the thickness of plate was increased, the region with residual stress was expanded. The gradient of residual stress within plate was reduced during the leveling process. But the residual stress itself was not removed at the ranges of tested conditions. From the measured residual stress distribution within the plate, camber of plate cut to small width was predicted exactly within error range of experiment.

• 한국기계가공학회지
• /
• 제16권4호
• /
• pp.53-61
• /
• 2017

Turbocharger is a device for increasing the power of a vehicle engine. The control plate is the main component for fixing the vane of the turbocharger. Now, the control plate is made of austenite steel cutting after the casting process. It has excellent corrosion, heat resistance and mechanical characteristics of material. However, present the process is made by cutting after casting. when cutting is processed after casting, so materials, processing time, and processing energy are lost. Therefore, this study proposes a process to powder compact use of stainless steel Deklak2 and to minimize amount of cutting through net shape process. The mechanical properties of Deklak2 were verified by tensile test, hardness test and relative density measurement, and the governed equation was defined. Also, the curvature radius 1, 2 and the density, affects the shape, were selected as the design parameters, and the best process conditions was proposed through the Taguchi method and the evaluation of SN ratio. And then prototype molds were fabricated and compared with the results of the finite element analysis for the verification, and it was found that the tendency of relative density and dimension was coincided. Therefore, it was found that the amount of cutting can be minimized by only the net shape process after the sintering process and it can be applied to mass production.

• Journal of Welding and Joining
• /
• 제21권2호
• /
• pp.3-8
• /
• 2003

• Structural Engineering and Mechanics
• /
• 제73권6호
• /
• pp.631-640
• /
• 2020

Using backup plate is one of the most commonly used methods to decrease drilling-induced delamination of composite laminates. It has been shown that, the size of the delamination zone is related to the vertical element of cutting force named as thrust force. Also, direct control of thrust force is not a routine task, because, it depends on both drilling parameters and mechanical properties of the composite laminate. In this research, critical feed rate and thrust force are predicted analytically for delamination initiation in drilling of composite laminates with backup plate. Three common theories, linear elastic fracture mechanics, classical laminated plate and mechanics of oblique cutting, are used to model the problem. Based on the proposed analytical model, the effect of drill radius, chisel edge size, and backup plate size on the critical thrust force and feed rate are investigated. Experimental tests were carried out to prove analytical model.

• 한국CDE학회논문집
• /
• 제2권4호
• /
• pp.267-275
• /
• 1997

A ship-block cutting module is being developed as part of a computational system for a ship design. The module supports product-information to other modules in design process and displays ship-blocks in cutting-operation. Welding-information is essential to process-planning and scheduling. In the module, ship-blocks are modeled by Plate-Objects and then divided into several cutting pieces. The module automatically creates Welding-Objects containing welding-information in the process. Since the module is connected to WWW(World Wide Web), users in various platforms can access the models simultaneously In addition, users can check manufacturing constraints by inspecting a virtual model.