Glass-Reinforced Epoxy-Resin Pipe for Pipe-Type Cable

Cable engineers have recognized for many years that losses which occur in the steel pipe of pipe cable systems appreciably increase ac resistance and greatly reduce possible ampacity of such systems. Nonmagnetic pipes did not offer a practical solution to the problem since available materials contributed essentially the same degree of loss to the system as steel pipes. Hence, from time to time, engineers have focused their attention on nonmetallic pipes as a means of reducing losses. This work shows that one of three plastic pipes examined by the authors effectively stopped the entrance of moisture and caused no deterioration of the cable or pipe oil. Therefore, from a technical standpoint, it provided an effective enclosure for pipe cable. However, the cost of such pipes is still too high to make them economically feasible.