Automatic Weighing and Ratioing of Solids

Plants which process materials in the form of bulk solids have not been able to use control to as great an extent, primarily due to the lack of measuring equipment capable of providing the same types of continuous automatic control available with liquid flow meters. A conveyor belt idler is supported on a rigid carriage … Read more

Estimating Data for Open Pit Haulage Trucks

In 1955, before planning an accelerated stripping program, Chino Mines Div. began an engineering study to improve data for estimating truck haulage costs for any future haulage layout. The study aimed to develop: 1) significant unit costs, 2) a method of estimating travel time from which truck needs and future stripping rate could be determined, … Read more

Comparison of 2400 and 4160 Volt Distribution Systems for Concentrators

Concentrating plants, in common with other types of industrial plants, cannot operate without, electric power. The electric distribution system and utilization equipments therefore, must be carefully considered in all phases of plant design. Two important aspects of proper distribution and usage of electric power are the selection of voltage levels and the methods of system … Read more

How to Determine the Strength of a Mine Roof

In an earlier phase of the investigation, an experimental room was progressively mined to an areal dimension of 50 by 100 feet. As the dimensions of the room were increased, the roof separated into horizontal layers that were loaded only by their own weight. The maximum stress and the elastic behavior of the lowest roof … Read more