Engineering Wonders of the World
Volume I

ENGINEERING IN THE WORLD’S OIL FIELDS. 337 system of these lines, thousands of miles long, upon which Oil Pipe Lines. millions of pounds have been spent. The pumping of light oils and kerosene through pipes presents no particular difficulty; but when dense, viscous crude oils have to be forced great distances, the friction rifling causes a rotary motion which drives the heavier water to the outside, and makes it form a frictionless layer between the piping and the oil. On the American oil fields it is customary for the lines connecting individual properties with the main pumping stations of the dis- AN OIL FIELD IN A FOREST. is enormous and the power required large. In California it was found impossible to pump some of the heavy oils along the completed mains, unless mixed with lighter varieties or with water, to reduce the friction. At times the oil has been heated to render it more fluid. A special rifled piping has recently been introduced to help to solve the problem. It is claimed that if heavy oil and water be pumped together through these pipes, the (1.408) trict to be of 2, 3, or 4 inch bore, where- as the main trunk lines have a diameter ranging from 4 to 8 inches. At intervals of from ten to fifty miles or more, accord- ing to the nature of the country, an inter- mediate pumping station is required, where the oil is received into tanks from the pre- ceding station and pumped along to the next. The trunk lines are of heavy lap-welded, screw-jointed pipes, able to stand a pressure 22 vol. ii.