Overhead transmission line conductors are manufactured in stranding machines whose design affects the strains and stresses involved in forming the strands into helices. The residual stresses following stranding influence the handling characteristics of the finished cable.
Stranding machines fall into two general classes relative to these stresses: rigid-head on one hand, and planetary and tubular stranders on the other. This monograph analyzes the geometry of conductor design, and then derives the strains and stresses due to manufacture in these strander types, leading to equations for the residual moments and torques in the strands of the finished conductor.
About the Author
Charles B. Rawlins is a consultant in the field of overhead conductor dynamics, having retired in 1991 from a 42 year career with Alcoa Laboratories. He has conducted research in aeolian vibration, galloping and wake induced oscillation of overhead conductors; short circuit and 'sticking' behavior of bundled conductors; and self damping, fatigue and aerodynamic characteristics of conductors. He is author of 38 papers and articles in these fields, and was author of the chapters on conductor fatigue and conductor galloping, and was co author of the chapter on wake induced oscillation, in the EPRI Transmission Line Reference Book, "Wind Induced Conductor Motions," published in 1979.
