Pressure surge reflector for pipe type cable system
The development and testing of a pressure surge reflector designed to reduce the pressure seen at potheads during an electrical failure in a pipe-type cable system are described. The reflector is designed to protect the potheads from failing because of a pressure surge that may be large enough to fracture the porcelain, particularly when the electrical failure is physically close to the pothead. Tests indicate that the gaskets in the pothead-base-riser pipe flanges will rupture and leak dielectric fluid at a pressure surge of 900-1200 psi when the bolts are torqued to specified values. Destruction of the high-strength pothead design may first occur in the range of 1600-1800 psi. Therefore, it is possible that an electrical failure in the cable pipe in close proximity to the cable end will initiate leaks of dielectric fluid at the gaskets rather than destroy the pothead. The prototype reflector lowers the pressure significantly, bringing the pressure surge below the factory pressure test level for standard potheads. >