TABLE OF CONTENTS The catenary is the curve assumed by a string or chain of uniform weight hanging freely between two supports. The cables of a suspension bridge, if uniformly loaded, assume the form of the catenary curve. It has, therefore, considerable importance in structural engineering.
When a part such as a drum, rotor, crankshaft, pulley, etc., is properly tested for balance while revolving, and any appreciable lack of balance is corrected on the basis of such test, the part is said to be in running or dynamic balance. Special balancing machines are used to determine the magnitude and location of unbalanced masses while the part is revolving; hence, the test is applied under operating conditions, which is not true of the test for static or standing balance.
A material generally used in the form of wire, in which a steel wire is covered with a coating of copper. It is produced either by alloying the copper with the surface of the metal or by welding it onto the surface. When the copper is alloyed with the surface, it is brought to a molten state before being applied, while, when welded to the surface, it is merely in a plastic state.
Thermostatic bimetal made in different types for automatically controlling temperature ranges of from 50 degrees F. to 1000 degrees F. Used for automatically controlling the operation of devices either heated or cooled by electricity, oil, or gas, as,...
