1938: Mining

The United States is second to no country in the world in the variety and value of the products from its mines. Large quantities of iron, coal, copper, lead, silver, and zinc are mined; in fact, tin and tungsten are the only two common industrial metals not found. With such mineral wealth, mining and the equipment necessary have been well developed.

During the past year, further steps have been taken to make both open cut and underground mining safer for workers; also to check silicosis; to make underground mining healthier by improved ventilation, in some mines by installing air conditioning systems. Continued attempts have been made to put out a fire in a large coal mine in Ohio, which has been burning for several years, causing losses of thousands of dollars.

For mining operations there have been developed improved blasting power, cutters, loaders, conveyors, and hoists, also automatic mucking and loading machines. In some mines the cars into which the loose ore is now mechanically loaded are drawn by air-operated or electric-operated locomotives.

Economies have been effected by the use of alloy iron and steel in mining equipment; thus the amount of ore handled has been increased, and a longer life had for machine parts subject to corrosive action from mine water. Besides dragline buckets, skips, and shovels, mine cars have been built of low alloy high strength steels, with an appreciable saving in weight and in power required to move them. For handling corrosive mine water, pipe and fittings have been made of high chromium steel; while pump parts subject to corrosion and abrasion have been cast of alloy iron.

It is interesting to note that airplanes are now employed to transport mining equipment and supplies to remote and inaccessible regions, as in Alaska, South America, and New Guinea. To one mine in New Guinea upwards of 20,000 tons of machinery were so transported.