Monitoring Method of Hydraulic Long Auger Drilling Process Based on Cognitive Interaction

Abstract A build-up process is used to manufacture printed wiring boards (PWBs) for high-density circuits. Presently, CO2 laser beams are used to drill blind via holes (BVHs) that connect copper foils. The Cu-direct drilling process has received considerable attention but is problematic because it produces a copper overhang due to the complex processing phenomena. This report focuses on monitoring scattered matter by Cu-direct laser drilling with a high-speed camera and clarifying the factors related to processing quality while verifying the results by CFD (Computational Fluid Dinamics) analysis. Previous research has shown that processing progress can be made from temperature information using the two-color image method that can measure temperature without contact. However, the two-color image method generates noise in the temperature range (500–3000 °C) which is treated in this research. Filtering was possible by using the RGB data of each pixel on the image. By focusing on laser fluence, it became possible to estimate the laser irradiation time that can guarantee the quality in the drilled hole (BVH) in single pulse continuous irradiation.

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On-Line Monitoring of Drill Wear Using Air-Coupled Audio Microphone when Drilling Composite Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.590.645 ◽

2014 ◽

Vol 590 ◽

pp. 645-650 ◽

Cited By ~ 1

Author(s):

Eshetu D. Eneyew ◽

Mamidala Ramulu

Keyword(s):

Composite Materials ◽

Tool Wear ◽

High Speed ◽

Cutting Tool ◽

Flank Wear ◽

High Speed Steel ◽

High Rate ◽

Drilling Process ◽

Monitoring Method ◽

On Line

The condition of the cutting tool when drilling composite materials is the controlling factor for the surface integrity of hole produced. The high rate of tool wear when drilling composite materials makes finding a way to monitor the condition of the cutting tool without interrupting the drilling process a great necessity. Inspecting the condition of the drill between or during the drilling process is not practical or economical. In an attempt to tackle this problem, a new approach of on-line tool wear monitoring method using an air-coupled audio microphone is proposed. An experimental investigation was conducted on multi-directional carbon fiber reinforced plastic (CFRP) composite material using a high speed steel (HSS) drill. The result shows that, the amplitude of the acoustic signal from the microphone decreases when the amount of flank wear increases and the amplitude of thrust force and torque increases with the increase of the flank wear. This result demonstrates that the proposed approach can be used as an effective and economical tool for on-line monitoring of cutting tool condition.

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Anti-Collision Distance Prediction Model Based on Spherical Wave Propagation Theory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.333-335.1736 ◽

2013 ◽

Vol 333-335 ◽

pp. 1736-1741

Author(s):

Gang Liu ◽

Hua Liang Liu ◽

Bao Sheng He

Keyword(s):

Prediction Model ◽

Elastic Waves ◽

Spherical Wave ◽

Warning System ◽

Measurement Model ◽

Drilling Process ◽

Monitoring Method ◽

Collision Warning ◽

Shallow Strata ◽

Distance Prediction

Inspired by the personal monitoring method in the anti-collision section drilling, the cluster well anti-collision monitoring and early warning system are developed to prevent the well bore collision in the drilling process. Distance prediction model of the warning system is developed based on the theory of elastic waves in spherical spreading and absorption attenuation. By monitoring the well casing vibration and then the data processing, the relative distance between the drill bit and adjacent well casing is obtained in real time. If the estimating possibility of well collision is occurred, then the alarm is given. The results show that the measurement model was effective in shallow strata for anti-collision warning. The model can improve the effect of present anti-collision monitoring, and provides a guarantee for the safe and efficient drilling.

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