An Investigation of the Mechanics and Noise Associated with Coal Cutting

1981 ◽  
Vol 103 (3) ◽  
pp. 257-269 ◽  
Author(s):  
R. S. Becker ◽  
G. R. Anderson ◽  
J. Kovac
Keyword(s):  
Underground Mining ◽  
Cutting Tools ◽  
Health And Safety ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Analytical Models ◽  
Mining Machine ◽  
Cutting Mechanics ◽  
Coal Cutting ◽  
Continuous Mining

The results of a laboratory investigation of coal cutting mechanics and noise are presented. These experiments were performed using a linear cutting apparatus that operates over a broad cutting speed range. The influence of several coal cutting parameters on the noise, force, productivity, and specific energy associated with linear cuts was ascertained. Some basic theoretical aspects of coal cutting mechanics and noise generation are discussed, and the results of the laboratory experiments are used to formulate analytical models of the coal cutting forces and noise. The analytical model for coal cutting noise is then generalized to account for the more important effects of rotary cutting. Based on the generalized model, an estimate of the sound pressure level at an operator’s position is made for a typical continuous mining machine. It is concluded that by employing linear rather than rotary cuts, using deeper depths of cut, slower cutting speeds, and more efficient cutting tools, it is possible to reduce the level of coal cutting noise, as well as provide benefits to other important areas of health and safety in underground mining.

Effect of Operator Position on the Incidence of Continuous Mining Machine/Worker Collisions

2007 ◽  
Vol 51 (20) ◽  
pp. 1416-1420
Author(s):  
John R. Bartels ◽  
Dean H. Ambrose ◽  
Sean Gallagher
Keyword(s):  
Response Times ◽  
Health And Safety ◽  
Mining Machine ◽  
Workplace Relationships ◽  
Continuous Miner ◽  
Work Posture ◽  
Close Proximity ◽  
Continuous Mining ◽  
Machine Speed ◽  
Machine Work

Remote operation of continuous miners has enhanced the health and safety of underground miners in many respects; however, numerous fatal and non-fatal continuous miner struck-by accidents have occurred when using remote controls. In an effort to prevent these injuries, NIOSH researchers at Pittsburgh Research Laboratory examined the workplace relationships between continuous miner operators and various tramming modes of the equipment using motion captured data, predicted operator response times, and field- of- view data to determine causes of operator-machine struck-by events in a virtual mine environment. Factors studied included machine speed, direction of escape, operator facing orientation relative to the machine, work posture, distance from machine, and operator anthropometry. Close proximity to the machine, high machine tramming speeds, a right-facing orientation and operator positioning near the tail all resulted in high risk of being struck. It is hoped that this data will provide an improved rationale for operator positioning for remotely operated continuous miners.

The Application of FEA in High-Speed Cutting

2011 ◽  
Vol 287-290 ◽  
pp. 104-107
Author(s):  
Lian Qing Ji ◽  
Kun Liu
Keyword(s):  
High Speed ◽  
Feeding Rate ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Material Model ◽  
Friction Model ◽  
Cutting Depth ◽  
High Speed Cutting ◽  
Key Technologies

The history and application of the FEA are briefly presented in this paper. Several key technologies such as the building of material model, the establishment of the chip - tool friction model as well as meshing are described. Taking the high-speed cutting of titanium alloy (Ti - 10V - 2Fe - 3Al) as an example , reasonable cutting tools and cutting parameters are determinted by simulating the influences of cutting speed, cutting depth and feeding rate on the cutting parameters using FEA.

Life Prediction of Cutting Tool by the Workpiece Cutting Condition

2011 ◽  
Vol 223 ◽  
pp. 554-563 ◽  
Author(s):  
Noemia Gomes de Mattos de Mesquita ◽  
José Eduardo Ferreira de Oliveira ◽  
Arimatea Quaresma Ferraz
Keyword(s):  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Operating Conditions ◽  
Production Costs ◽  
Depth Of Cut ◽  
Cutting Condition ◽  
Workpiece Material ◽  
The Cost

Stops to exchange cutting tool, to set up again the tool in a turning operation with CNC or to measure the workpiece dimensions have direct influence on production. The premature removal of the cutting tool results in high cost of machining, since the parcel relating to the cost of the cutting tool increases. On the other hand the late exchange of cutting tool also increases the cost of production because getting parts out of the preset tolerances may require rework for its use, when it does not cause bigger problems such as breaking of cutting tools or the loss of the part. Therefore, the right time to exchange the tool should be well defined when wanted to minimize production costs. When the flank wear is the limiting tool life, the time predetermination that a cutting tool must be used for the machining occurs within the limits of tolerance can be done without difficulty. This paper aims to show how the life of the cutting tool can be calculated taking into account the cutting parameters (cutting speed, feed and depth of cut), workpiece material, power of the machine, the dimensional tolerance of the part, the finishing surface, the geometry of the cutting tool and operating conditions of the machine tool, once known the parameters of Taylor algebraic structure. These parameters were raised for the ABNT 1038 steel machined with cutting tools of hard metal.

Evaluation of Mining Activities Using a Scenario Interview Approach

1998 ◽  
Vol 42 (15) ◽  
pp. 1108-1112
Author(s):  
Fred Turin ◽  
Lisa Steiner ◽  
Kim Cornelius
Keyword(s):  
Underground Mining ◽  
Mining Machine ◽  
Mining Activities ◽  
Underground Coal Mining ◽  
Safety Issues ◽  
Safe Work ◽  
Mining Conditions ◽  
Continuous Mining ◽  
Machine Operator ◽  
Scenario Approach

NIOSH researchers have been examining underground coal mining activities in order to evaluate work crew hazards. In 1994 a continuous mining machine operator was killed by falling roof during extended cut mining. Many aspects of the incident were used by NIOSH researchers to develop a scenario interview. The goal was to provide a realistic framework for acquiring frank and detailed insights. The interview consists of two sections. The first describes the underground mining conditions. The second recounts the fatal incident. Each section is supplemented by a diagram and a set of questions addressing relevant safety issues. The interview was administered at three mines that actively take extended cuts. Researchers found the scenario approach to be an effective interview tool as well as an effective hazard awareness and safe work practices training platform.

scholarly journals Optimisation of Cutting Tool and Cutting Parameters in Face Milling of Custom 450 through the Taguchi Method

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Harun Gokce
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Tool Wear ◽  
Taguchi Method ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Cutting Tool Wear ◽  
Wide Range

Stainless steels with unique corrosion resistance are used in applications with a wide range of fields, especially in the medical, food, and chemical sectors, to maritime and nuclear power plants. The low heat conduction coefficient and the high mechanical properties make the workability of stainless steel materials difficult and cause these materials to be in the class of hard-to-process materials. In this study, suitable cutting tools and cutting parameters were determined by the Taguchi method taking surface roughness and cutting tool wear into milling of Custom 450 martensitic stainless steel. Four different carbide cutting tools, with 40, 80, 120, and 160 m/min cutting speeds and 0.05, 0.1, 0.15, and 0.2 mm/rev feed rates, were selected as cutting parameters for the experiments. Surface roughness values and cutting tool wear amount were determined as a result of the empirical studies. ANOVA was performed to determine the significance levels of the cutting parameters on the measured values. According to ANOVA, while the most effective cutting parameter on surface roughness was the feed rate (% 50.38), the cutting speed (% 81.15) for tool wear was calculated.

scholarly journals Burr edge occupancy: edge finishing index for milling machined parts

2019 ◽  
Vol 43 (2) ◽  
pp. 248-255 ◽  
Author(s):  
Seyed Ali Niknam ◽  
Azziz Tiabi ◽  
Victor Songmene
Keyword(s):  
Aluminium Alloys ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Machining Time ◽  
Slot Milling ◽  
Burr Size ◽  
Machined Parts ◽  
Edge Finishing ◽  
Selection Of

Machining burrs are formed at all machined workpiece edges. One useful solution to decrease machining time and cost, in particular for milling parts, is to generate machined parts edges with minimum burr. This article proposes burr edge occupancy ηs as an index to evaluate deburring difficulty and, consequently, adequate selection of suitable deburring methods. Initially the sensitivity of ηs to cutting parameters must be evaluated. We investigated the main governing factors on ηs when slot milling two types of aluminium alloys (from different families) that are used in the automotive and aerospace industries. The cutting parameters that led to edges with minimum ηs are presented. It was found that, unlike most burr size attributes, ηs is sensitive to variation of the cutting parameters used: cutting speed, family of material, and cutting tools. Lower ηs means less time and effort for deburring and edge finishing of machined parts. Furthermore, ηs measurement is more convenient than the procedures used to measure other burr size attributes, including burr height (bh) and burr thickness (bt).

Multi-Constrained Analysis of Metal Cutting and its Application

2013 ◽  
Vol 589-590 ◽  
pp. 38-44
Author(s):  
Gang Liu ◽  
Ming Chen ◽  
Peng Nan Li ◽  
Qing Zhen Bi ◽  
Bao Cai Guo
Keyword(s):  
Thermal Conductivity ◽  
Stainless Steel ◽  
Metal Cutting ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Cutting Process ◽  
Optimization Strategy ◽  
First Time

The concept of multi-constrained analysis of the cutting process is presented for the first time in the paper. The paper adopts a method to solve an important problem which is how to judge the influence of constrains during the cutting process. The research results are applied for HSS drills for cutting stainless steel. On the basis of the multi-constrained analysis combined with methods of simulations and standard experiments, the optimum methods are provided for structure, coating and cutting parameters of cutting tools. For geometric structure of tools, optimization is to increase thickness of cutting and rake angle. Coating optimization strategy is choosing high temperature hardness and low thermal conductivity coating. Optimization of cutting parameter is to adjust feed fate, then select proper cutting speed. The conclusion of paper is helpful for the cutting optimization.

Experimental Research on High-Speed Machining Pearlitic Gray Cast Iron

2006 ◽  
Vol 315-316 ◽  
pp. 459-463 ◽  
Author(s):  
Yi Wan ◽  
Zhan Qiang Liu ◽  
Xing Ai
Keyword(s):  
Cast Iron ◽  
High Speed ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
High Speed Machining ◽  
Workpiece Surface ◽  
Tool Materials ◽  
Boron Nitrogen

High-speed machining (HSM) has received great interest because it leads to an increase of productivity and a better workpiece surface quality. However, tool wear increases dramatically due to the high temperature at the tool/workpiece interface. Proper selection of cutting tool and cutting parameters is the key process in high-speed machining. In this paper, experiments have been conducted to high speed milling pearlitic cast iron with different tool materials, including polycrystalline cubic boron nitrogen, ceramics and coated cemented carbides. Wear curves and tool life curves have been achieved at various cutting speeds with different cutting tools. If efficiency is considered, Polycrystalline Cubic Boron Nitrogen cutting tool materials are preferred in finish and semi-finish machining. According to the different hardness of cast iron, the appropriate range of cutting speed is from 850 m/min to 1200m/min.

Three-dimensional finite element modeling of effect on the cutting forces of rake angle and approach angle in milling

2016 ◽  
Vol 231 (2) ◽  
pp. 83-88 ◽  
Author(s):  
Kadir Gok ◽  
Hüseyin Sari ◽  
Arif Gok ◽  
Süleyman Neseli ◽  
Erol Turkes ◽  
...  
Keyword(s):  
Cutting Tools ◽  
Three Dimensional ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Depth Of Cut ◽  
Dry Cutting ◽  
Milling Operations ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

In this study, milling operations were carried out using AISI 1040 specimens steel in dry cutting conditions. The cutting tools used in the experiment include P20 tool steel and they also have three different approach angles (45°, 60°, 75°) and rake angles (0°, −6°, −12°). In milling experiments, cutting parameters with a depth of cut of 1.5 mm, cutting speed of 193 m/min, and feed rate of 313 mm/min were selected. A comparison was presented between the force values which were obtained by measured value and predicted with numerical simulations, and then a good agreement was found between measured and predicted force values. As result of, it was observed that the rake and approach angles were effective in milling operations.

scholarly journals Method for Friction Force Estimation on the Flank of Cutting Tools

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Luis Huerta ◽  
Alejandro Lozano-Guzmán ◽  
Horacio Orozco-Mendoza ◽  
Juan Carlos Jauregui-Correa
Keyword(s):  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Friction Model ◽  
Machining Process ◽  
Major Influence ◽  
Rake Face ◽  
Force Estimation ◽  
Friction Forces ◽  
The Stability

Friction forces are present in any machining process. These forces could play an important role in the dynamics of the system. In the cutting process, friction is mainly present in the rake face and the flank of the tool. Although the one that acts on the rake face has a major influence, the other one can become also important and could take part in the stability of the system. In this work, experimental identification of the friction on the flank is presented. The experimental determination was carried out by machining aluminum samples in a CNC lathe. As a result, two friction functions were obtained as a function of the cutting speed and the relative motion of the contact elements. Experiments using a worn and a new insert were carried out. Force and acceleration were recorded simultaneously and, from these results, different friction levels were observed depending on the cutting parameters, such as cutting speed, feed rate, and tool condition. Finally, a friction model for the flank friction is presented.

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