In CableCAD, both geometrical and material nonlinear
effects are modeled. Large deformations (elongation, rotation, and
bending), nonlinear stress-strain curves, plastic wire indentation
into adjacent cylindrical layers, and circumferential layer locking
(at 100% coverage) are included in the model. Such nonlinear
effects can be significant in predicting cable behavior, especially
for torque-balanced and stress-balanced cable constructions.
Indentation of a circular wire into an adjacent
cylindrical layer can significantly affect the axial and torsional
properties of a cable. To determine wire indentation, CableCAD
uses the Durometer (Shore A) hardness of the indented cylindrical
layer. Indentations that occur in use, as well as initial
indentations produced during manufacturing or preloading, can be
included in the model. No assumptions related to filling
of wire interstices are required to estimate this important effect
on cable behavior.
Automatic Torque Balance
CableCAD automatically can adjust the lay angle
of any helical wire layer to minimize the cable torque developed
over the range of applied cable tension.