A novel tool monitoring approach for diamond wire sawing

AbstractMobile diamond wire sawing is a highly flexible, productive and, versatile cutting process. Accordingly, it is used in many areas, such as the dismantling of nuclear power plants or wind turbines. Despite the widespread use of the process, the cutting process requires continuous manual monitoring by the machine operator. This is due to the continuously changing cutting conditions. A common process error is tool breakage. It is often caused by the displacement of the grinding segments (cutting beads). Due to the cutting speed (up to 30 m/s), these failures cannot be detected and prevented by the machine operator. However, a measuring system or process monitoring does not exist yet. Accordingly, a damaged diamond wire can become hooked, which often results in wire breaks. As a result, grinding segments break away from the wire, which can lead to deadly accidents. Therefore, a new approach for monitoring the tool for diamond wire grinding will be investigated. The paper is divided into five sections. First, the requirements for the sensor system are derived. After the selection of a measuring principle and the functional verification in the grinding process, the monitoring approach is presented and features for monitoring the tool with regard to the displacement of grinding segments are described. It was shown that the developed approach is suitable for monitoring the diamond wire tool during the sawing process. The investigation on a prepared diamond wire tool also demonstrated that the feature allows the detection of displacing grinding segments already from 2 mm.

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Experimental Investigation of Temperatures in Diamond Wire Sawing Granite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.404.185 ◽

2009 ◽

Vol 404 ◽

pp. 185-191 ◽

Cited By ~ 2

Author(s):

Hui Huang ◽

N. Guo ◽

Xi Peng Xu

Keyword(s):

Experimental Investigation ◽

Feed Rate ◽

Cutting Speed ◽

Front Part ◽

Short Term ◽

Diamond Wire ◽

Cutting Zone ◽

Background Temperature ◽

Diamond Wire Sawing

The background temperatures in the sawing of granite with a diamond wire were measured by foil thermocouple. The influences of the measuring position in the cutting zone, cutting speed, feed rate and coolant on the temperature were investigated. The results indicated that the background temperature would be stable after a short-term rise. It was shown that the background temperature increased with cutting speed, but there was no obvious relationship between the background temperature and feed rate. The maximum background temperature appeared at the front part of the cutting zone at a lower feed rate. With an increase of feed rate, the background temperature at the middle of the cutting zone was the highest. The coolant had an obvious influence on the maximum background temperature.

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Fundamental Study on Underwater Cutting of 50 mm-Thick Stainless Steel Plates Using a Fiber Laser for Nuclear Decommissioning

Applied Sciences ◽

10.3390/app12010495 ◽

2022 ◽

Vol 12 (1) ◽

pp. 495

Author(s):

Kwan Kim ◽

Moo-Keun Song ◽

Su-Jin Lee ◽

Dongsig Shin ◽

Jeong Suh ◽

...

Keyword(s):

Stainless Steel ◽

Laser Power ◽

Laser Cutting ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Cutting Speed ◽

Cutting Surface ◽

Focal Position ◽

Underwater Laser

With nuclear power plants worldwide approaching their design lifespans, plans for decommissioning nuclear power plants are increasing, and interest in decommissioning technology is growing. Laser cutting, which is suitable for high-speed cutting in underwater environments and is amenable to remote control and automation, has attracted considerable interest. In this study, the effects of laser cutting were analyzed with respect to relevant parameters to achieve high-quality underwater laser cutting for the decommissioning of nuclear power plants. The kerf width, drag line, and roughness of the specimens during the high-power laser cutting of 50 mm-thick stainless steel in an underwater environment were analyzed based on key parameters (focal position, laser power, and cutting speed) to determine the conditions for satisfactory cutting surface quality. The results indicated that underwater laser cutting with a speed of up to 130 mm/min was possible at a focal position of 30 mm and a laser power of 9 kW; however, the best-quality cutting surface was obtained at a cutting speed of 30 mm/min.

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Application of Electrical Impedance Measurements’ Method for Studies of Bubble Flows

Devices and Methods of Measurements ◽

10.21122/2220-9506-2021-12-3-183-193 ◽

2021 ◽

Vol 12 (3) ◽

pp. 183-193

Author(s):

I. A. Konovalov ◽

A. A. Chesnokov ◽

A. A. Barinov ◽

S. M. Dmitriev ◽

A. E. Khrobostov ◽

...

Keyword(s):

Nuclear Power ◽

Power Plants ◽

Electrical Impedance ◽

Wire Mesh ◽

Measuring System ◽

Gas Content ◽

The Core ◽

Multicomponent Flows ◽

Liquid Flows ◽

Good Agreement

One of the important tasks in carrying out a computational justification of the reliability and safety of equipment that is part of the projected nuclear power plants today is the modeling of the bubbly regime of the coolant flow. In this regard the aim of this work is the use of extended methods of using matrix conductometric systems which are widespread in research practice for study of gas-liquid flows.The work uses a method of primary processing of experimental data aimed at eliminating of excess conductivity in the cells of the developed wire mesh sensor which makes it possible to obtain the values of the true volumetric gas content in the investigated area.Subsequent analysis of the possibilities to estimate the volumes of registered gas bubbles by the gradient method as well as the size of the interface in the sensor cells which plays a key role in modeling the interfacial heat and mass transfer.Comparison of readings values with the control instruments cues showed a good agreement. The presented work is an adaptation of the use of a conductometric measuring system for the study of multicomponent flows with the aim of further application for the study of two-component flows in the channels of the core simulator using wire mesh sensors.

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Application of Cdznte Detectors for Control of Initial Enrichment of Fresh Nuclear Fuel at Refueling

EPJ Web of Conferences ◽

10.1051/epjconf/202022503002 ◽

2020 ◽

Vol 225 ◽

pp. 03002

Author(s):

O.V. Maslov ◽

V.A. Mokritskiy ◽

A.V. Sokolov

Keyword(s):

Nuclear Fuel ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Fuel Cycle ◽

Nuclear Safety ◽

Measuring System ◽

Uranium Isotopes ◽

Semiconductor Detectors ◽

Cdznte Detectors

The task of determining the initial enrichment of nuclear fuel (NF) at nuclear power plants in real time is relevant for both economic indicators of operation of the power unit and for all components of nuclear safety (nuclear safety, security and safeguards). The technology used by nuclear fuel cycle companies is not suitable for use at nuclear power plants. It is proposed to use a measuring system based on CdZnTe semiconductor detectors designed to control the burn-up depth of nuclear fuel for estimating the initial enrichment of fresh nuclear fuel in fuel assemblies (FA). The initial enrichment is estimated with help of the gamma radiation of uranium isotopes of fresh nuclear fuel. A distinctive feature of the system that has been developed is the use of passive tomography technology to take into account the self-absorption of radiation in the FA. The promise of the proposed method for estimating initial enrichment is confirmed by experimental measurements and simulation results. It is shown that the system developed makes it possible to determine the enrichment of nuclear fuel, taking into account its profiling by the volume of FA. Also, the results of measurements confirmed the possibility of using the proposed technical solutions for CdZnTe detectors to create portable monitoring systems for special nuclear material in the field. The solution of this task is of great importance for national security.

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Application of the Correlation Measurement Method for Reconstructing of the Velocity Profile with Spatial and Temporal Discretization in Studies of the Hydrodynamics of Turbulent Flows Based on the Matrix Conductometry Method

Devices and Methods of Measurements ◽

10.21122/2220-9506-2021-12-4-292-300 ◽

2021 ◽

Vol 12 (4) ◽

pp. 292-300

Author(s):

S. M. Dmitriev ◽

A. E. Khrobostov ◽

D. N. Solncev ◽

A. A. Barinov ◽

A. A. Chesnokov ◽

...

Keyword(s):

Data Collection ◽

Turbulent Flows ◽

Flow Rate ◽

Nuclear Power ◽

Power Plants ◽

Correlation Method ◽

Measuring System ◽

Reliability Of Results ◽

The Matrix ◽

Influence Of Noise

The correlation method for measuring of the coolant fl rate is used in the operation of nuclear power plants and is widespread in research practice including study of turbulent fl hydrodynamics. However the question of its applicability and possibilities in studies using the matrix conductometry method remains open. Earlier the algorithm for determining of the correlation fl rate using a conductometric measuring system was highlighted and the error of the results obtained was estimated and the dependence of the influence of noise and the time of data collection on the reliability of results was investigated. These works were carried out using two independent mesh sensors and the issue of the resolution of local velocity components was not covered. The purpose of this work was to test the correlation method for measuring velocity with temporal and spatial sampling using two-layer mesh conductometric sensors.As the result velocity cartograms were obtained over the cross-section of the experimental model with quasi-stationary mixing and the value of the average flow rate is in good agreement with the values obtained from the standard flow meters of the stand. Also measurements were carried out at a non-stationary setting of the experiment and realizations of the flow rate and velocity components of the flow at the measuring points were obtained.Analysis of the obtained values allows to conclude about the optimal data collection time for correlation measurements, as well as the reliability of results.

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The Effects of Ion Implantation on the Surface Features of Inconel 600

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118333 ◽

1985 ◽

Vol 43 ◽

pp. 288-289

Author(s):

John D. Rubio

Keyword(s):

Grain Boundary ◽

Ion Implantation ◽

Nuclear Power ◽

Power Plants ◽

Surface Region ◽

Selective Dissolution ◽

Boundary Region ◽

Near Surface ◽

Inconel 600 ◽

Steam Generator Tubing

The degradation of steam generator tubing at nuclear power plants has become an important problem for the electric utilities generating nuclear power. The material used for the tubing, Inconel 600, has been found to be succeptible to intergranular attack (IGA). IGA is the selective dissolution of material along its grain boundaries. The author believes that the sensitivity of Inconel 600 to IGA can be minimized by homogenizing the near-surface region using ion implantation. The collisions between the implanted ions and the atoms in the grain boundary region would displace the atoms and thus effectively smear the grain boundary.To determine the validity of this hypothesis, an Inconel 600 sample was implanted with 100kV N2+ ions to a dose of 1x1016 ions/cm2 and electrolytically etched in a 5% Nital solution at 5V for 20 seconds. The etched sample was then examined using a JEOL JSM25S scanning electron microscope.

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