Abstract: A corona tube is provided wherein the tube is flexible so that it can fit on any three dimensional container rim. The tube can be a flexible steel tube which is a standard commercial variety of corrugated steel tube which is usually used to contain wires or the like. The tube has a slotted edge along its length, is cut to a length to the periphery of the rim and bent in the shape of the rim. The slot of the flexible tube is placed over the edge of the rim and thereafter the tube can be welded to the rim.

Abstract: A cylindrical housing for a high voltage circuit breaker is filled with sulfur hexafluoride and receives three parallel elongated puffer interrupters arranged with their axes on the apices of an equilateral triangle. A single triangular support plate receives one end of each interrupter and supports them in cantilever. The triangular plate is fixed to the housing by thin steel straps affixed to respective apices of the plate. Filter bags in a removable tray are disposed along the horizontal bottom of the housing. Bushings enter the tank through openings in the tank wall. The openings receive slotted flexible tubes which wrap around the slot edges to serve as corona rings. The bushings each have an integral central conductive stud and conductive end plate.

Abstract: A high-voltage power circuit breaker contains a plurality of phases which are contained in respective separate tanks which may be filled with sulfur hexafluoride. Each phase contains a respective trip-free contact operating mechanism connected to the interrupter contacts within the tank. Each of the trip-free operating mechanisms are closed simultaneously by a pneumatic closing mechanism contained in only one of the poles and connected to the other pole operating mechanisms by a common operating rod. Each of the poles are simultaneously closed by the pneumatic operating mechanism, and each pole can open independently of the other poles through its own trip-free operating mechanism.

Abstract: A stationary contact structure for a gas blast circuit interrupter consists of a conductive hollow cylinder which is slotted to define contact fingers, and the ends of the contact fingers are inwardly deformed so that the ends of the fingers closely abut one another to prevent inward deflection of the contact fingers to a degree which would exceed their elastic limit.