• Title/Summary/Keyword: Boring Cutter

Search Result 38, Processing Time 0.02 seconds

A Study on the Development of a Step Cutter with Hybrid Process of Drilling and Boring (드릴, 보링 공정복합형 스텝 커터의 개발)

  • Hwang, Jong Dae;Heo, Yun Nyoung;Oh, Ji Young;Jung, Yoon Gyo;Cho, Sung Lim
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.7 no.3
    • /
    • pp.30-35
    • /
    • 2008
  • As demands for being economical, precise drilling process is on the increase. Therefore, the objective of this study is to develop a step cutter that can be controllable through micro dimension and can be changed from separate manufacturing processes of drilling and boring into an integrated one. In order to attain this object the step cutter is designed with a 3D geometric modeling and the design could be modified easily by using parametric modeling methodology. Also, collision is not occurred during manufacturing process because of cutting simulation. The step cutter is assembled by parts made up of 5-axis machining and sintering. Validation tests are accomplished. They show that developed cutter has characteristics such as reduction of machining time as well as the good surface roughness of the machined hole. Indeed, reliability could be obtained from a durability test.

  • PDF

A Study on the Change in Hole Precision with Slenderness Ratio of Boring Cutter (보링커터의 세장비에 따른 구멍 정밀도 변화에 관한 연구)

  • Chun, Se-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.16 no.5
    • /
    • pp.7-12
    • /
    • 2017
  • It is assumed that the buckling and cutting conditions depending on the slenderness ratio will affect the machining quality of the rotary boring tool mounted on a milling machine. In this study, the boring cutter was designed and fabricated to precisely create the Ø30 hole. Through the performance evaluation, the accuracy of the hole according to the slenderness ratio and cutting conditions was analyzed, and the following conclusions were obtained. The higher the RPM, the smaller the change in the working diameter, and the smaller the hole. Next, the smaller the slenderness ratio, the smaller the change in straightness due to the change in cutting conditions. Finally, the slenderness ratio also affects the tendency for changes in the concentricity. The larger the slenderness ratio, the more sensitive the concentricity to changes in cutting conditions.

A study on the Change of Diameter Based on Cutting Conditions in AL6061-T4 Boring Machining (AL6061-T4의 보링가공 시 절삭조건에 따른 직경 변화에 관한 연구)

  • Chun, Se-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.19 no.6
    • /
    • pp.49-54
    • /
    • 2020
  • The purpose of this study is to investigate the effects of the change in the spindle speed and the feed rate on the diameter change of a hole using a boring cutter for the internal boring process of AL6061-T4 alloys. The experimental results are quantitatively analyzed by applying the factor analysis and the response surface analysis of the experimental design method. The tendency of the diameter change according to the change in the spindle speed and feed level is also evaluated. During the internal boring process of AL6061-T4 alloys, the main factor affecting the diameter change is the spindle speed in which the diameter decreases as the number of revolutions increases. In addition, the diameter tends to increase as the feed is increased; however, as the number of spindle revolutions increases, the influence of the feed decreases.

A Study On Heat Transfer and Flow Characteristics for Boring in Sewer by Rotating Cutter Tool (회전노즐장비 작동시 하수관내의 열전달 및 유동현상에 관한 연구)

  • Park Young-Ki;Lee Jang-Choon;Lee Dong-Joo
    • Journal of Environmental Science International
    • /
    • v.15 no.1
    • /
    • pp.95-100
    • /
    • 2006
  • Heat transfer and flow characteristics in a pipe in which the rotating cutting tool for boring a underground pipe without digging were considered in this study. The amount of heat generation due to the friction between the rotating cutter and pipe wall, mixing (low of air and water injected to cool down are the two important factors to design the boring machine Computational fluid dynamics analysis using the Eulerian mixture model and the standard $\kappa-\varepsilon$ turbulence model was used to analyze the complex phenomena in a pipe during the process. Results show that pipe wall temperature decreased with increasing the cooling water inlet velocity. it is also shown that pipe wail temperature was lowered when the cutter rotation speed was increased until 600 rpm. There was no further cooling effect over 600 rpm.

Application of Rotary Cutting Test for Performance Assessment of Tunnel Boring Extender (TBE의 굴착성능 평가를 위한 회전식 절삭시험의 적용)

  • Jeong, Hoyoung;Jeon, Seokwon;Cho, Jung-Woo
    • Tunnel and Underground Space
    • /
    • v.32 no.4
    • /
    • pp.243-253
    • /
    • 2022
  • In this study, the cutting efficiency of TBE (Tunnel Boring Extender) was evaluated by using rotary cutting tester. In the rotary cutting test, a specimen which has a drilled hollow hole at the center was made of rock-like material. The specimen was cut by UDC (undercutting disc cutter) with spiral cutting path to simulate the cutting process of TBE. The cutting forces and specific energy were evaluated under different cutting conditions. The results indicated that the cutter forces of UDC linearly increased with the vertical and radial penetration depths. Among the three directional cutter forces, the normal force is larger than other force components. While the specific energy decreased with the two penetration depths, in particular, it was presumed that the specific energy was minimized at a certain value of the ratio of radial to vertical penetration depth.

Three Dimensional Numerical Analysis on Rock Cutting Behavior of Disc Cutter Using Particle Flow Code (3차원 입자결합모델을 이용한 디스크 커터의 암석절삭에 관한 연구)

  • Lee, Seung-Joong;Choi, Sung-Oong
    • Tunnel and Underground Space
    • /
    • v.23 no.1
    • /
    • pp.54-65
    • /
    • 2013
  • The LCM (Linear Cutting Machine) test is one of the most powerful and reliable methods for designing the disc cutter and for predicting the TBM (Tunnel Boring Machine) performance. It has an advantage to predict the actual load on disc cutter from the laboratory test on the real-size large rock samples, however, it also has a disadvantage to transport and/or prepare the large rock samples and to need an extra cost for experiment. In order to overcome this problem, lots of numerical studies have been performed. In this study, the PFC3D (Particle Flow Code in 3 Dimension) has been adopted for numerical analysis on optimum cutter spacing and failure aspects of Busan Tuff. The optimum cutting condition with s/p ratio of 16 and minimum specific energy of $14MJ/m^3$ was derived from numerical analyses. The cutter spacing for Busan Tuff had the good agreements with those of LCM test and numerical analysis by finite element method.

Introduction to Research Trend of Real-Time Measurement for Wear of TBM Disc Cutter (TBM 디스크커터의 마모량 실시간 계측을 위한 연구현황)

  • Min-Sung, Park;Min-Seok, Ju;Min-Sung, Cho;Jun, Lee;Jung-Joo, Kim;Hoyoung, Jeong
    • Tunnel and Underground Space
    • /
    • v.32 no.6
    • /
    • pp.478-490
    • /
    • 2022
  • TBM disc cutter, which is the main cutting tool of tunnel boring machine (TBM), is replaced when it is excessively worn during the boring process. Disc cutters are usually monitored by workers at cutterhead chamber, and they check the status and wear amount of cutters. Because cutterhead chamber is usually in dangerous circumstance due to high pressure and instability of excavation surface, the measurement by manpower occasionally results in inaccuracy of measurement result. In order to overcome the limitations, the real-time disc cutter monitoring techniques have been developed in some foreign countries. This paper collected the current status of disc cutter monitoring system from the literature. Several types of sensors are used to measure the cutter wear, and it is believed that the collected information can be useful reference when similar domestic technologies are developed in the future.

Numerical analysis on the estimation of optimal disc cutter angle in transition cutter zone (전이 구간(트렌지션 커터존)의 최적 디스크커터 각도 산정에 관한 수치해석 연구)

  • Lee, Sang Yun;Song, Ki-il
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.23 no.1
    • /
    • pp.1-12
    • /
    • 2021
  • In the design of a tunnel boring machine (TBM), the excavation efficiency of the equipment depends on the design of the cutter head, which is directly in contact with the ground. Especially, the allocation of disc cutter is crucial issue. Disc cutters can be divided into center cutter zone, inner cutter zone and transition cutter zone depending on where they are placed. Many studies have been conducted to identify optimal cutting conditions for face cutters. However, research to determine the optimal cutting conditions for the transition cutter has been relatively incomplete. In this study, to identify the optimal cutting conditions for the transition cutter, numerical analysis using discrete element method was performed, and the specific energy curve according to the angle between the transition cutters was drawn to find out the optimum cutting conditions. The results show that the angle between the transition cutters showing minimum specific energy in the transition cutter zone is 9°. Transition cutter zone was divided into three sections according to the slope angle of the transition cutter. It is also found that, the greater the slope angle of the transition cutter. This finding shows good agreement with the present design of transition cutter zone.

Prediction of replacement period of shield TBM disc cutter using SVM (SVM 기법을 이용한 쉴드 TBM 디스크 커터 교환 주기 예측)

  • La, You-Sung;Kim, Myung-In;Kim, Bumjoo
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.5
    • /
    • pp.641-656
    • /
    • 2019
  • In this study, a machine learning method was proposed to use in predicting optimal replacement period of shield TBM (Tunnel Boring Machine) disc cutter. To do this, a large dataset of ground condition, disc cutter replacement records and TBM excavation-related data, collected from a shield TBM tunnel site in Korea, was built and they were used to construct a disc cutter replacement period prediction model using a machine learning algorithm, SVM (Support Vector Machine) and to assess the performance of the model. The results showed that the performance of RBF (Radial Basis Function) SVM is the best among a total of three SVM classification functions (80% accuracy and 10% error rate on average). When compared between ground types, the more disc cutter replacement data existed, the better prediction results were obtained. From this results, it is expected that machine learning methods become very popularly used in practice in near future as more data is accumulated and the machine learning models continue to be fine-tuned.