The benefits of polymeric armored cables

摘要

During installation, power and control cables will experience tension and sidewall bearing pressure. In an effort to minimize costs and maximize reliability, many installation contractors are faced with the requirement to install long lengths of cable without the luxury of splices. It is these types of installations that often result in the cable being exposed to excessive mechanical forces (especially sidewall bearing pressures). During installation, the mechanical forces should be monitored as a means of controlling the mechanical stresses and protecting the integrity of the cable. Typically, manufacturers and cable installers have used various ways to protect cables from high sidewall bearing pressures. Cable manufacturers use metal clad armor of either aluminum interlocked armor (AIA) or continuously corrugated and welded (CCW) metal armor. Cable installers have options of increasing the bending radius the cable is pulled around or installing shorter cable pulls and splicing the sections. This paper will detail the development and evaluation of an innovative power cable design that provides increased mechanical protection without the use of metallic armor while providing protection against moisture and hydrocarbons. The new design incorporates a polymer layer that has been shown to improve both the mechanical toughness of electrical power cables while maintaining the flexibility needed to install the cable. The data presented supports that polymeric armored cable provides 5 times better impact performance than metallic armored products and from 2 to 6 times the sidewall bearing pressure limits of metallic armored cables. This allows the manufacturer to produce longer lengths of cable, and the installers to install longer lengths of cable without the added expense and risk incurred due to installing splices.