Mechanical & Maintenance

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 … Read more

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 … Read more

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 … Read more

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 … Read more

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 … Read more

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 … Read more

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 … Read more

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 … Read more

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 … Read more