Chromium Electroplating
Electroplating is a widely utilized but little understood process, the fact that the average person is in contact with dozens of plated items daily without even being aware that they are electroplated is evidence of the success of the process, although a complete explanation of electrodeposition involves thermodynamics and modern theories of bonding and catalytic […]
Slurry Pulp Distributor
The practical and effective pulp distributor here presented is believed to be of a completely new and innovative design. It was developed at the San Nicolas Plant of the Marcona Mining Company in Peru, where it has been thoroughly plant tested using iron ore slurries of a particularly abrasive nature. As indicated, the motivation for […]
Plant Layout – Cold and Remote Areas
Basic things to remember in plant design for cold and remote areas are, everything in these areas is more expensive due to long and difficult supply lines. Fuel is expensive and would be a major cost item even if it were not expensive, due to the extended periods of low temperatures. Building volumes should therefore […]
How Maintenance Practice Affects Wire Rope Life in Surface Coal Mining Draglines
As part of a larger study to identify factors influencing the practical operating life of wire rope used on large draglines in surface coal mining, field trips to operating surface coal mines were made during late 1975. Wire rope performance information was obtained from personnel at thirteen mine sites west of the Appalachians. Data Acquisition […]
Launder Design Procedure
The design of slurry launders has usually been based on strictly empirical concepts. An examination of the most common procedures reveals that they do not account for many of the variables that are recognized as significant for slurry transport. These may include flow rate, volume concentration of solids, solids specific gravity, solids size distribution, particle […]
Mine Drum Hoist Rope Maintenance
Mining Companies employ the use of mine hoists to transfer ore, men and materials through a vertical shaft or slope. With varying depths, payloads and equipment, it is necessary to select a rope construction that is best suited for these parameters and that can also provide the most economical cost per ton hoisted. If the […]
Hydrodynamic Bearings for Large Diameter Machines
The hydrodynamic bearing has the following characteristics: Lubricant film thickness and pressure are maintained by lubricant which is drawn into a wedge shaped zone between the journal and the bearing, due to their relative velocity and the viscosity of the lubricant. Lubricant flow conditions are laminar. Lubricant film thickness is sufficient to prevent metal to […]
Drag & Hoist Ropes of Dragline Performance
Typical dragline rigging includes several sets of ropes: hoist ropes, drag ropes, dump ropes and boom suspension ropes. The drag and hoist ropes contribute most to the dragline operating cost, and significantly influence dragline productive time. Both work in very difficult conditions and wear out rapidly. As a result frequent rope changes are required at […]
Conveyor Belt Cleaning Systems
Objective Reduce the number of conveyor-related accidents in the mining industry by providing recommendations for effective operation of conveyor belt cleaning systems. The Problem Troughed belt conveyors provide effective and efficient materials transport and their use has increased throughout the mining industry. Carryback, the spillage that accumulates under the belt, is a problem even with […]
How to Predict Electric Motor Failures
A system capable of monitoring a mine electrical power system to detect incipient electrical component failure could significantly improve power system safety and availability. The U.S. Bureau of Mines funded a contract with The Pennsylvania State University (Penn State) to establish the theoretical and technical framework for such a system. This report briefly outlines the […]