A fluid flow and cooling system and method are provided. The system has a substantially cylindrical tube shape and is configured to be installed in a circuit breaker for allowing the flow of fluids while dissipating heat from said fluids. The system comprises a plurality of openings on each of front and back surfaces, the openings of the front surface being connected to the openings of the back surface by a plurality of side passages. By having a plurality of side passages for the flow of fluids, heat dissipation may be improved compared to previous circuit breakers tubes for dispensing arc quenching fluid. The method cools a fluid flowing in a cooling device having side passages.

A movable part of a circuit breaker for a gas-insulated switchgear is proposed. The movable part includes a puffer cylinder, a nozzle, and a main contact. An outer rib at the rear end of the nozzle is hooked to a hook rib at the front end of the hook part of the puffer cylinder. A chamber guide is provided inside the puffer cylinder so that the nozzle is immobilized. The main contact is mounted on the outer surface of the front end of the hook part. Thus, the number of components constituting the movable part of the circuit breaker is reduced, and the number of bolting points is reduced, thereby greatly reducing man-hours in an assembly work and preventing a main contact separation from occurring due to bolt loosening.

A load-break switch has a housing holding insulation gas at ambient pressure; a first main contact and a second main contact being movable relative to each other in an axial direction of the switch; a first arcing contact and a second arcing contact being movable relative to each other in the axial direction and defining an arcing region where an arc is formed during a current breaking operation, wherein the arcing region is located radially inward from the first main contact; a pressurizing system pressurizing a quenching gas during the current breaking operation; and a nozzle system arranged to blow the pressurized quenching gas onto the arc. The first main contact includes at least one pressure release opening to allow gas flow in a radial outward direction. A total area of the pressure release opening suppresses a reduction of gas flow out of the pressure release opening.

A contact piece for a high-voltage circuit breaker includes at least a contact pin and a contact carrier. The contact carrier is configured to mechanically fasten the contact pin in the high-voltage circuit breaker. The contact pin includes a contact shaft. The contact carrier and the contact shaft are formed as a monolithic contact element. A method for producing a contact piece is also provided.

A gas-insulated low- or medium-voltage load break switch includes: a housing defining a housing volume for holding an insulation gas at an ambient pressure; a first arcing contact and a second arcing contact arranged within the housing volume, the first and second arcing contacts being movable in relation to each other along an axis of the load break switch and defining a quenching region in which an arc is formed during a current breaking operation; a pressurizing system having a pressurizing chamber arranged within the housing volume for pressurizing a quenching gas from an ambient pressure p.sub.0 to a quenching pressure p.sub.quench during the current breaking operation; and a nozzle system arranged within the housing volume for blowing the pressurized quenching gas in a subsonic flow pattern from the pressurization chamber onto the arc formed in the quenching region during the current breaking operation. The nozzle system includes at least one nozzle arranged for blowing the quenching gas from an off-axis position predominantly radially inwardly onto the quenching region.

A movable part of a circuit breaker for a gas-insulated switchgear is proposed. The movable part includes a puffer cylinder, a nozzle, a main contact, etc. An outer rib at the rear end of the nozzle is hooked to a hook rib at the front end of the hook part of the puffer cylinder. A chamber guide is provided inside the puffer cylinder so that the nozzle is immobilized. The main contact is mounted on the outer surface of the front end of the hook part. In the present invention, the number of components constituting the movable part of the circuit breaker is reduced, and the number of bolting points is reduced, thereby greatly reducing man-hours in an assembly work and preventing a main contact separation from occurring due to bolt loosening.

An electrical switching device includes a first switching contact piece and a second switching contact piece. The switching contact pieces can be displaced in relation to each other. The first switching contact piece is surrounded by a fluid flow guiding device. An enveloping contour of a flow duct, disposed between the fluid flow guiding device and the first switching contact piece, is greater at its end facing the second switching contact piece than an enveloping contour of the first switching contact piece at its end facing the second switching contact piece.

A gas-insulated low- or medium-voltage switch for system voltages within 1 to 52 kV and for up to 2000 A rated current includes first and second contacts being movable in relation to each other along an axis of the switch and defining a quenching region in which an arc is formed during a current breaking operation; and an arc-extinguishing system for extinguishing the arc during the current breaking operation. The arc-extinguishing system may include a pressurization system with a puffer chamber, and a nozzle system connecting the pressurization system with the quenching region, the nozzle system having a nozzle at its outlet for blowing the pressurized quenching gas onto the arc formed in the quenching region during the current breaking operation; and a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system. The arc-extinguishing system further includes a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system.

A gas-insulated load break switch and a gas-insulated switchgear having a gas-insulated load break switch. The gas-insulated load-break switch has a housing defining a housing volume for holding an insulation gas at an ambient pressure; a first main contact and a second main contact, the first and second main contacts being movable in relation to each other in the axial direction of the load break switch; a first arcing contact and a second arcing contact, the first and second arcing contacts being movable in relation to each other in an axial direction of the load break switch and defining an arcing region in which an arc is formed during a current breaking operation, wherein the arcing region is located, at least partially, radially inward from the first main contact; a pressurizing system having a pressurizing chamber for pressurizing a quenching gas during the current breaking operation; and a nozzle system arranged and configured to blow the pressurized quenching gas onto the arc formed in the quenching region during the current breaking operation, the nozzle system having a nozzle supply channel for supplying at least one nozzle with the pressurized quenching gas. The first main contact includes at least one pressure release opening formed such as to allow a flow of gas substantially in a radial outward direction, wherein the total area of the at least one pressure release opening is configured such that during a supply of the pressurized quenching gas, a reduction of the flow of gas out of the pressure release opening is suppressed.

An electrical switching device includes a first switching contact piece and a second switching contact piece. The switching contact pieces can be displaced in relation to each other. The first switching contact piece is surrounded by a fluid flow guiding device. An enveloping contour of a flow duct, disposed between the fluid flow guiding device and the first switching contact piece, is greater at its end facing the second switching contact piece than an enveloping contour of the first switching contact piece at its end facing the second switching contact piece.