322. Wire Weight Estimating

Paper

Abstract

This paper was presented at the Twenty-first Annual National Conference of the Society of Aeronautical Weight Engineers at Seattle, Washington, May 14-17, 1962. The purpose of this paper is to provide a method of reducing the number of unsolved mysteries in wire weight predictions that have existed within the missile industry. The present method is specifically designed for use on hardware programs, but can be applied to advanced design programs with some reservations.
Mathematical and physical analyses were used in the preparation of Wire Weight Estimating to determine wire weights. Only qualified weights personnel were used in determining actual measurements to validate values presented in this paper.
For this study, various wire gages and insulations were used, ranging in size from 0 to 20 gage for both shielded and unshielded wires. Miscellaneous wire bundles were tightly tied in accordance with standard installation procedures to obtain circumference measurements. The actual weight per foot of the bundles was then compared to the respective measured circumferences. These circumferences versus weight comparisons were then tabulated and plotted on graphs. These graphs were surprisingly consistent for all of the weights and circumference comparisons made. The individual graphs were then superimposed to derive a single weight estimating curve. Ten or larger gage wire does not fall entirely within the span of the weight estimating curve. However, small amounts of this wire, (20% or less of the bundle end area) could be used within a bundle and the results proved satisfactory.
The method presented has been used to calculate weights with a +/- 6% variation of the actual weight. This variation was strictly dependent on the detail and accuracy with which the estimator worked. A definite knowledge of wire types being evaluated can improve the accuracy and minimize the effort in wire weight estimating. Accurate wire length readings should be strongly emphasized. This length is the factor used in multiplying the established circumference unit weight per foot to determine the total wire weight.