Mining Engineering Commons^™

Characteristic Surfaces For Three-Position Function Generation With Planar Four-Bar Mechanisms, Clark R. Barker, P. L. Tso

Mining Engineering Faculty Research & Creative Works

This paper considers the relationship between the three-position function-generation problem and the solution space for planar four-bar mechanisms. The two infinities of solutions possible are mapped in a plane to determine the locations where particular types of mechanisms occur. It is possible to generate a contour in the mapping plane which joins together all solutions which possess a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space to ascertain the overall characteristics of potential solutions to the design problem. A numerical example is used for illustrative purposes, but the results can …

Mechanical Stemming Construction For Blast Holes And Method Of Use, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A stemming construction for a blast hole loaded with an explosive charge, comprising a tapering wedge member dispersed in the blast hole outwardly of the explosive charge with its narrower end facing outwardly toward the mouth of the blast hole, and particulate stemming material in the blast hole outwardly of the wedge member. Detonation of the explosive drives the wedge member into the stemming material to wedge the stemming material against the walls of the blast hole. The wedge member is preferably cone-shaped and can be provided with a stabilizing rod to prevent it from tilting.

Operations-Based Training Strategy For Longwall Mining, R. Larry Grayson, Michael J. Klishis, Ronald C. Althouse, George M. Lies

Mining Engineering Faculty Research & Creative Works

A system that can be used to pinpoint the specific training needs of operations and assist in the design and upgrading of focused training approaches can benefit longwall mining. It can be directed at systematically correcting performance discrepancies at an individual, crew, or mine level, and also to challenge workers and management toward attaining improved performances. Such an approach involves a combination of features, such as diligence in monitoring and evaluating performances, thorough coordination in implementing changes, and effective use of operational data.

The Bureau of Mines, through contract with the Mining Extension Service of West Virginia University, has developed …

Knowledge Organization And Inference Engine For The Wvu Face Decision Support System, S. Carrow, R. S. Nutter Jr., R. S. Raman, N. A. Reddy, Y. V. Reddy, R. Larry Grayson

Mining Engineering Faculty Research & Creative Works

The knowledge-based organization for the West Virginia University Face Decision Support System is given, along with the initial development of the associated inference engine. The knowledge base contains generic knowledge about underground coal mines that utilize continuous miners. A typical knowledge entry is given, and the inference engine methodology is explained. The engine utilizes this knowledge with data from monitoring systems and from interaction with the section foreman, to assist in making section management decisions and plans.

Disintegration Of Wood, Marian Mazurkiewicz

Mining Engineering Faculty Research & Creative Works

Disintegration of wood especially for production of wood pulp for making paper, involving subjecting a body of wood, more particularly a debarked log, to liquid jet action with the energy of the liquid as it impacts on the body such as to effect disintegration of the body into particles.

Three-Position Function Generation Of Planar Four-Bar Mechanisms With Equal Deviation Transmission Angle Control, Clark R. Barker, Gwo Huey Shu

Mining Engineering Faculty Research & Creative Works

In an earlier work, it has been shown that all of the potential solutions to a given problem may be represented in an αβ-plane which can be subdivided into mechanism types. Further, the regions in the αβ-plane may represent two possible forms of assembly plus a change of form class which are not valid solutions. In this paper, we provide a third-order polynomial which defines the locus in the αbeta-plane of solutions which have equal deviation of their transmission angle from the ideal of 90° throughout the entire range of motion. When these solutions are mapped into a Cartesian plane, …

Three-Position Function Generation Of Planar Four-Bar Mechanisms With Equal Deviation Transmission Angle Control, Clark R. Barker, Gwo Huey Shu

Mining Engineering Faculty Research & Creative Works

This paper is an extension of earlier work on mapping of three-position function generation of planar four-bar mechanisms. Previously, it has been shown that all of the potential solutions to a given problem may be represented in an aft plane which can be subdivided into mechanism types. Further, the regions in the aft plane may represent two possible forms of assembly plus a change of form class which are not valid solutions. In this paper, we provide a third-order polynomial which defines the locus in the aft-plane of solutions which have equal deviation of their transmission angle from the ideal …

Characteristic Surfaces For Three-Position Motion Generation With Planar Four-Bar Mechanisms., Clark R. Barker, J. Baumann

Mining Engineering Faculty Research & Creative Works

This paper considers the relationship between the three-position motion generation problem and the solution space for planar four-bar mechanisms. After one half of the basic four bar had been selected, two infinities of solutions still remained. These solutions are mapped in a plane to determine where the particular types of mechanisms occur. A contour is then generated in the mapping plane which joins together all solutions which share a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space and in the Cartesian plane in which the motion generation is defined.

Characteristic Surfaces For Three Position Function Generation With Planar Four Bar Mechanisms, Clark R. Barker, P. L. Tso

Mining Engineering Faculty Research & Creative Works

This paper considers the relationship between the three-position function generation problem and the solution space for planar four bar mechanisms. The two infinities of solutions possible are mapped in a plane to determine the locations where particular types of mechanisms occur. It is possible to generate a contour in the mapping plane which joins together all solutions which possess a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space to ascertain the overall characteristics of potential solutions to the design problem. A numerical example is used for illustrative purposes, but the …

Integrated Detonator Delay Circuits And Firing Console, Lawson J. Tyler, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A detonation system for use with supply of electrical energy has user operable firing console for selectably transmitting unit identification information, firing delay time information and selections from a command set including Output, Delay, Fire (Time), Abort, Power Up (Arm), Input, and Store. The console displays responses or information digested from responses by electrical delay detonators to the commands. The detonators have explosive, a capacitor for storing energy from the supply to set off the explosive, circuitry for charging the capacitor from the supply and transferring the energy from the capacitor to the explosive in response to first and second …

Characteristic Surfaces For Three-Position Motion Generation With Planar Four-Bar Mechanisms, Clark R. Barker, J. Baumann

Mining Engineering Faculty Research & Creative Works

This paper considers the relationship between the three-position motion generation problem and the solution space for planar four-bar mechanisms. After one half of the basic four bar had been selected, two infinities of solutions still remained. These solutions are mapped in a plane to determine where the particular types of mechanisms occur. A contour is then generated in the mapping plane which joins together all solutions which share a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space and in the Cartesian plane in which the motion generation is defined. Significant …

Equivalent Electron Fluence For Space Qualification Of Shallow Junction Heteroface Gaas Solar Cells, John W. Wilson, L. V. Stock

Mining Engineering Faculty Research & Creative Works

It is desirable to perform qualification tests prior to deployment of solar cells in space power applications. Such test procedures are complicated by the complex mixture of differing radiation components in space which are difficult to simulate in ground test facilities. Although it has been shown that an equivalent electron fluence ratio cannot be uniquely defined for monoenergetic proton exposure of GaAs shallow junction cells, an equivalent electron fluence test can be defined for common spectral components of protons found in space. Equivalent electron fluence levels for the geosynchronous environment are presented.

Thrust-Impact Rock-Splitter, George Bromley Clark, T. F. Lehnhoff

Mining Engineering Faculty Research & Creative Works

A rock splitting tool having elongate laterally expanding metal pressure bars or feathers and an axial sliding wedge or spreader for radially separating the feathers, the wedge being driven by the combined and superimposed forces of a hydraulic thrust servomotor and an impact hammer. The driving paths for transmitting forces to the wedge are coaxial and partially in series and partially in parallel.

Method And Apparatus For Water Jet Drilling Of Rock, David A. Summers, Marian Mazurkiewicz, Dwight J. Bushnell, James Blaine

Mining Engineering Faculty Research & Creative Works

Rock drilling method and apparatus utilizing high pressure water jets for drilling holes of relatively small diameter at speeds significantly greater than that attainable with existing drilling tools. Greatly increased drilling rates are attained due to jet nozzle geometry and speed of rotation. The jet nozzle design has two orifices, one pointing axially ahead in the direction of travel and the second inclined at an angle of approximately 30° from the axis. The two orifices have diameters in the ratio of approximately 1:2. Liquid jet velocities in excess of 1,000 ft/sec are used, and the nozzle is rotated at speeds …

An Investigation Of Combined Thermal Weakening And Mechanical Disintegration Of Hard Rock, George Bromley Clark, T. F. Lehnhoff, Vernon Dale Allen, Mahendrakumar Ramkrishna Patel

Mining Engineering Faculty Research & Creative Works

"The research under modified Contract No. H0220068 has been devoted to experimental thermal-mechanical fragmentation of Missouri red granite in place, and to supporting theoretical analyses. The results of the previous year's experimental work showed that thermal stresses are several times more effective in fragmenting hard rock when they are created within the rock rather than upon the surface. Also, large blocks {4-foot cubes) are not adequate to simulate the response of in situ rock.

Based upon laboratory tests an experimental round was designed analogous to an explosive blasting round with coiled wire heating elements placed in drill holes. Three displacement …

Penetration In Granite By Jets From Shaped-Charge Liners Of Six Materials, Ronald R. Rollins, George Bromley Clark, H. N. Kalia

Mining Engineering Faculty Research & Creative Works

A new application of theory for three-dimensional collapse of conical liners shows why the two-dimensional analysis may offer a good approximation. Shaped-charge design parameters and rock target properties were investigated to determine their effects on penetration and breakage. Several metals, liner thicknesses, cone angles and standoff ranges for each were investigated. Effective standoff is greater for aluminum than more dense metals. Jets from the 60° monel, brass and steel liners gave the deepest penetration in granite. Jets from copper and brass liners gave equal penetration for 42° apex angles. Liners containing zinc produced small slugs or none at all. The …

Combined Thermal Weakening And Mechanical Disintegration Of Hard Rock, George Bromley Clark, T. F. Lehnhoff, Gary F. Fenton, M. R. Patel, Jaw K. Wang, Vernon Dale Allen

Mining Engineering Faculty Research & Creative Works

This investigation of the combined effects of thermal weakening and mechanical disintegration (thermomechanical fragmentation) was initiated with a view toward better understanding of the processes required for more rapidly and economically fragmenting or excavating hard rock. Boring machines for utility tunnels, transportation tunnels or mining operations may be able to utilize the advantages of processes such as thermomechanical fragmentation. Secondary fragmentation or rock crushing processes also can conceivably employ the data obtained from this study.