Abstract: A status detection apparatus for electrical equipment includes a plurality of distributed multiparameter sensors in a containment vessel or other fluid filled region of the electrical equipment. The sensors are capable of providing data relating to plural parameters of the fluid simultaneously at different positions in the fluid. The data provided by the sensors can be processed to permit localization of incipient faults or can indicate other operating states when combined with known flow data of the fluid through the electrical equipment. A method for detecting status of electrical equipment includes sensing parameters simultaneously at multiple locations in the fluid and determining operating status based on the sensed parameters.

Abstract: A container (2) with an oil immersed core (1) and windings has corrugated walls. Bushing insulators (9,10) have pressure-resistant and water-resistant cable shoes (11). A tank encompasses another container (4) filled with insulating oil (3) and has pressure-resistant cable bushing (13) and connectors for electrical connections of the transformer.

Abstract: In an electric apparatus, insulating cylinders having different diameters are arranged in a shape of multiple cylinders between the iron core and the low voltage winding, between the low voltage winding and the high voltage winding and on the periphery of the high voltage winding. Spacers are separately arranged between layers of the plurality of insulating cylinders to form a plurality of insulating medium paths. A flow stopping member for stopping the flow of the insulating medium in the insulating medium paths which is made of an insulating material with a low density is arranged at at least one of the upper and lower ends of each of the insulating medium paths.

Abstract: This invention relates to a method of cooling an immersed induction coil, such as an ionising coil used in a vacuum processing chamber. The coil 10 may comprise a coiled hollow tube 11 through which coolant can flow when pumped by a pump 13. A valve 16 is provided so that air can be passed through the tube in either direction and the direction of flow is controlled by a controller 19, which acts on the valve 16. The rate of switching of the valve 16 can be determined by a process condition or by monitoring the temperature of the downstream coolant and/or the coil.

Abstract: This invention relates to a cooling system for a transformer. A winding defining a coil, including a duct having an open top and bottom, is sealed to a sleeve, thus forming a closed circulatory path. A fluid is retained and circulated within the circulatory path.

Abstract: An integral oil filter-pump system for an electric power device which involves a cabinet having an oil-filled compartment for containing the power device, as well as a circulation pump for circulating oil through the system, including the compartment for containing the power device.

Abstract: Insulating oil in electric power transmission switchgear such as a load tap changer for a transformer is filtered for removal of accumulated water and carbon particles. The filter and associated circulation pump is usually located in a separate cabinet external to the switchgear with circulation conduits connecting the filter, the pump and the switchgear reservoir. To prevent or minimize equipment damage that is presaged by excessive insulating oil temperature, oil flow within the oil circulation conduits is monitored for temperature excesses. Alarms are issued and electrical loads are disconnected upon detection of an excess temperature event. If desired, provision may be made for disconnected the jeopardized equipment from its respective service load.

Abstract: The invention, intended for large power transformers and industrial heat transfer installations, is systemic in nature and calls upon two components which complement each other, the first one effecting the continuous on-line de-gassing of an insulating or heat transfer medium by the application of a vacuum whose pressure reducing effect is compensated by hydrostatic pressure or the combination of an impeller downstream and a restrictor upstream of the pressurized part; the second component of the complementary system is constituted by an expansion space which is separated from a displaceable buffer liquid by a membrane.

Abstract: Described is a low-loss induction coil for heating and/or melting metallic materials, the coil having windings formed by lengths of hollow tubing carrying a fluid coolant. In the central zone of the induction coil, the current is carried by hollow conductors made of copper which at the same time form the hollow tubing. Fitted at least in the windings at one end of the coil is a current-carrying element in the form of at least one braid whose individual conductors are insulated from each other, while remaining windings are designed as hollow conductors connected to the current-carrying element. The use of braids as the current carrier leads, at the end of the coil, to a reduction in eddy-current losses caused by transverse magnetic fields, while the use of hollow conductors in the rest of the coil results in the mean distance between the current flux and the metallic material being heated being kept at the minimum and losses due to this distance thus kept low.

Abstract: An electrical apparatus, such as a transformer, includes an expandable internal chamber that is nonventing and completely and permanently sealed from the ambient environment. The chamber houses a core and coil assembly or other current-carrying conductor and is completely filled with dielectric fluid having a pressure less than one atmosphere. The enclosure walls are flexible and are permitted to bow inwardly and outwardly as the volume of the dielectric fluid changes due to thermal expansion and contraction. A method of processing the dielectric fluid and filling and sealing the transformer at sub-atmospheric pressure is also disclosed.

Abstract: An oil cooled inductive coupler for use with an inductive charging system that charges propulsion batteries of an electric vehicle. The coupler is connected to a power source by way of a coaxial cable that has power conductors for coupling power to the coupler, and cooling channels for coupling high dielectric strength cooling fluid to and from the coupler. The coupler has a housing with a flood box formed therein having an open interior that forms a conductor termination area. The cooling channels are coupled to the flood box, and the power conductors are terminated in the termination area and are exposed to the cooling fluid that is pumped therethrough to cool them. A heat exchanger having a fluid flow path therethrough is coupled to the flood box and permits the cooling fluid to circulate therethrough. A primary winding is secured or bonded to the heat exchanger, a magnetic puck is disposed in an opening in the heat exchanger, and upper and lower primary winding covers enclose the heat exchanger.

Abstract: A stationary reduction apparatus is arranged so that coil groups comprising plate type (or disc type) coils, which are stacked up in multiple layers with spacers inserted therebetween to traverse through a core whereby a refrigerant may pass through inter-layer clearances, are provided and divided into a plurality of coil sub-groups and every other coil sub-group of the divided coil sub-groups is surrounded by a refrigerant guide which is provided with an opening on its internal periphery and refrigerant flow ports on its external periphery, and the refrigerant is introduced into the refrigerant guide to flow in a horizontal direction through respective inter-layer clearances of the stacked-up coil groups, thereby the coil groups are effectively cooled without accelerating the velocity of refrigerant flow.

Abstract: A fluid cooled RF transmission cable, transformer primary or secondary winding, and induction heating coil incorporating litz cable is disclosed. The heating coil comprises: a litz cable including a bundle of mutually electrically insulated, intermixed wire filaments, and a coolant tube, surrounding the litz wire, for conveying a fluid for removing heat generated by the litz cable. Also a combined coolant and electrical connector for providing an electrical connection and coolant to an inductive heating coil including a coolant tube and a litz cable housed inside the coolant tube is described.

Abstract: A stationary reduction apparatus is arranged so that coil groups comprising plate type (or disc type) coils, which are stacked up in multiple layers with spacers inserted therebetween to traverse through a core whereby a refrigerant may pass through inter-layer clearances, are provided and divided into a plurality of coil sub-groups and every other coil sub-group of the divided coil sub-groups is surrounded by a refrigerant guide which is provided with an opening on its internal periphery and refrigerant flow ports on its external periphery, and the refrigerant is introduced into the refrigerant guide to flow in a horizontal direction through respective inter-layer clearances of the stacked-up coil groups, thereby the coil groups are effectively cooled without accelerating the velocity of refrigerant flow.

Abstract: A stationary reduction apparatus is arranged so that coil groups comprising plate type (or disc type) coils, which are stacked up in multiple layers with spacers inserted therebetween to traverse through a core whereby a refrigerant may pass through inter-layer clearances, are provided and divided into a plurality of coil sub-groups and every other coil sub-group of the divided coil sub-groups is surrounded by a refrigerant guide which is provided with an opening on its internal periphery and refrigerant flow ports on its external periphery, and the refrigerant is introduced into the refrigerant guide to flow in a horizontal direction through respective inter-layer clearances of the stacked-up coil groups, thereby the coil groups are effectively cooled without accelerating the velocity of refrigerant flow.

Abstract: The disclosure discusses impedance matching circuits based on parallel-resonant L-C tank circuits, and describes a low-loss design for an adjustable inductance element suitable for use in these parallel tank circuits. The application of an impedance matching circuit to a plasma process is also disclosed; in this context, a local impedance transformation circuit is used to improve power transfer to the plasma source antenna.

Abstract: An nonflammable insulating liquid is obtained by adding an emulsifying agent having a volume ratio of 1 to 3% to an insulating liquid containing a fluorocarbon liquid of at least 25% in a volume ratio to cause emulsification. In this liquid mixture, when polyol ester or dimethylcyloxane is used as the insulating liquid, an nonflammable insulating liquid that does not cause pollution or an environmental problem can be obtained. When tricresyl phosphate is used as the insulating liquid, an nonflammable insulating liquid having a dielectric constant close to that of insulating paper can be obtained. A liquid pipe for circulating a fluorocarbon emulsion in a tank is provided outside the tank, and a pump and a stirrer are connected midway along the liquid pipe to constantly stir the fluorocarbon emulsion, thereby preventing it from being separated into two layers. When a radiator is provided to the liquid pipe, the stirring system for the fluorocarbon emulsion can also serve as the cooling system.

Abstract: An inductive coil for heating a rotating roller is embedded in a plastic carrier. To cool the plastic carrier in the region of the coil, a cooling element in the form of a flat cooling chamber through which a fluid cooling medium can flow is provided on the front surface of the plastic carrier facing the roller periphery.

Abstract: A gas-insulated stationary induction electrical apparatus comprising a first closed vessel sealingly accommodating therein a main body having an iron core formed by laminating silicon steel sheets and also having at least one set of windings each consisting of a high-voltage winding and a low-voltage winding which are disposed apart from the iron core on both sides thereof, and a liquid medium for effecting cooling and insulation; a second closed vessel formed of an insulating material and sealingly accommodating therein the first closed vessel; and an insulating gas under a predetermined pressure which is sealed within the gap between the first and second vessels, wherein the induction apparatus main body is submerged in the liquid medium.

Abstract: A coil designed for providing a highly uniform magnetic field suitable for use in nuclear magnetic resonance computer-aided tomography is provided with preheating apparatus which uses forced circulation of warmed liquid along the path normally circulated with the cooling liquid whereby there are simulated the normal operating coil heating conditions even when the coil is not operating so that the start-up stabilization time can be shortened.

Abstract: A gas insulated electromagnetic induction appliance in which a non-condensing insulating gas and a condensing insulating coolant are confined, comprises (a) a pressure detector for detecting a pressure within the container vessel; (b) a gas reservoir connected to the container vessel through a gas discharging passageway including a pipe line, a first gas valve, a compressor, and a gas diffuser; a gas feeding passageway including a pipe line and a second gas valve; and a liquid feeding passageway including a pipe line and a liquid valve; (c) a definite quantity of insulating coolant confined in the gas reservoir; (d) a liquid surface detector for detecting a quantity of the insulating coolant in the gas reservoir; and (e) control means which controls the gas valve, the liquid valve, and the compressor to thereby regulate a pressure in the container vessel and a quantity of the liquid in the gas reservoir.

Abstract: The invention is relative with a gas-insulated electrical apparatus comprising a tank housing an electrical apparatus proper and in which a gas mixture consisting of a noncondensable insulating gas and a condensable refrigerant gas and a liquid phase of the condensable refrigerant gas are sealed, and a gas reservoir connected to said tank in the gas mixture feeding or receiving relation therewith. According to the invention, means are provided between the tank and the gas reservoir for selectively supplying said gas mixture from said tank into said gas reservoir or vice versa.

Abstract: An axially symmetric air-core choke coil for high voltage applications. The coil includes a plurality of radially concentric, helically wound layers of windings. Non-insulated wire cable is used to produce each winding. Therefore, adjacent turns of each winding, as well as adjacent layers are spaced from one another. Separation between adjacent turns of each layer is provided through longitudinally extending, non-conductive, strips which are circumferentially spaced around the outer periphery of each winding layer. The strips are folded radially inward at the open spaces between turns. The layers are separated by a plurality of longitudinally extending non-conductive bars. The bars can be positioned to overlap the strips. Numerous air gaps are thereby defined between adjacent turns and adjacent layers which allow air to easily flow in a radial direction into the center of the air-core coil.

Abstract: Large power transformers such as used at electrical generating plants utilize oil for cooling with the heat removed by air cooled radiators. Several air cooled radiators are removed from the transformers and the oil circulated through plate heat exchangers which provide a heat transfer path to a fluid cooling medium such as water. Flow transducers and electrical temperature sensors may be used to monitor the flow rates of the oil and water, and the temperature of the oil and water in various parts of the system. These parameters are controlled to maximize the transfer of waste heat from the transformer to the water. The heated water is then utilized to perform useful work. For example, in a power plant having package boilers, the boiler makeup water is preheated with the transformer waste heat thereby reducing the energy requirements of the system.

Abstract: A cooling apparatus for a gas insulated transformer has a tank which houses coils and an iron core and in which an electrically insulating gas is sealed. A reservoir housing the coils and having an outlet at its upper end is disposed inside the tank. Spray equipment with a plurality of spray nozzles is also disposed inside the tank. A first cooling unit for cooling the cooling medium flowing down in the tank and collected in the first cooling unit is disposed at the bottom of the tank. The cooling medium cooled by the first cooling unit is supplied to the reservoir and cools the coils while flowing through gaps therebetween. Some cooling medium is converted into vapor by the heat generated by the coils. The cooling medium cooled by the first cooling unit is further cooled by a second cooling unit and is sprayed into the interior of the tank from the spary nozzles. The vapor in the tank directly contacts the mist of the cooling medium sprayed from the spray nozzles and is condensed.

Abstract: This invention relates to improvements in a transformer apparatus in which a transformer unit insulated with insulating oil and a switch unit insulated with insulating gas are combined. The transformer unit is accommodated in a transformer tank filled with the insulating oil. The switch unit is accommodated in a switch tank filled with the insulating gas. The switch tank is disposed on the top of the transformer unit and made integral therewith such that these tanks are communicated with each other in the interior of the communicated tanks.

Abstract: Transformer, including copper windings, electrical insulation for the windings, the electrical insulation being formed of sections of solid and liquid insulating material, the liquid insulating material serving as a cooling liquid containing a chemical compound from the class of N,N'-dihydrazides as a copper deactivator in a cooling liquid flow, and a supply depot disposed in the cooling liquid flow containing the copper deactivator as a solid material.

Abstract: A gas/vapor electromagnetic induction machine comprises an annular coil container including two coaxial electrically insulating cylinders connected at lower ends to an annular bottom plate and coaxially disposed around an iron core within an enclosed tank charged with a non-condensable electrically insulating gas and a condensable cooling gas. A dripping pan receives a condensate of the cooling gas located on the lower portion of the tank through the operation of a pump and drops the condensate into the annular coil container and onto the iron core assembly located within the annular coil container. Thus a coil is always partially or entirely immersed in the condensate collected in the annular coil container.

Abstract: An eddy current system and method is disclosed for detecting flaws in hot pipe product. The system includes a detector test head (22) having a heat shield (24) defining a generally cylindrical inner wall through which the pipe passes longitudinally. The test head includes structure (50, 62, 64) for spirally directing water onto the inside surface without contacting the hot pipe as it passes through the heat shield. Debris is thereby removed from the space between the shield and the pipe, and the test head is effectively cooled and shielded from the heat of the pipe. Where the pipe is heated above its Curie temperature, such that the pipe is rendered non-magnetic, no normally required saturation coil is needed to magnetically saturate the pipe for eddy current testing, because the coolant flowing over the inner wall cools the test head but does not lower pipe temperature below the Curie point.

Abstract: Electrical inductive apparatus having a tank, an insulating and cooling liquid in the tank and an electrical winding structure immersed in the liquid, the liquid having a low vapor pressure and containing contaminants derived from various sources within the tank. Filter means associated with the liquid including a liquid recirculating device for degassing, demoisturizing, and filtering insoluble particles out of the liquid, whereby the liquid is decontaminated and upgraded in a continual process.

Abstract: A transformer with a controlled flow of cooling liquid has a pressure chamber (10) which, via a hydraulic connecting member (14), is connected to a circulating pump which is included in a cooling circuit arranged outside a transformer tank (1). The connecting member (14) has a cavity (19), which is substantially formed as a rotational paraboloid, whereby an inlet tube (21), arranged at one end of said cavity and tangentially thereto, is connected to the circulating pump. One end of the member (14) is directly connected to the pressure chamber (10), whereas the other end of said member is connected to a cooling liquid collecting chamber (13) positioned outside the pressure chamber and defined by the transformer tank. (FIG. 1.

Abstract: The quantity of SF.sub.6 gas dissolved in a halogenated dielectric coolant used in transformers can be determined by heating a sample quantity of the sample gas coolant to the point of cavitation and comparing the temperature and pressure at which cavitation first appears to a graphic representation of the relationship between concentration, pressure and temperature to obtain the gas concentration from the observed temperature point.

Abstract: Identical plates of essentially box-like form in which one sidewall of the box is notched out, and a transverse sidewall opposite the notch removed, the plates being stacked edgewise to form a duct assembly with alternatingly appearing openings at the top and bottom and on the front and rear side where the cutouts are positioned. The respective top and bottom openings are connected, respectively, to an ambient air manifold and a blower, and to the interior of the electronic cabinet, with the side cutouts facing, respectively ambient air and the interior of the cabinet to establish two separate air flow circuits and provide for dust-free and contamination free ventilation of the interior of the electronic cabinet while establishing efficient heat exchange by forced air flow of ambient air parallel to the ducts carrying dust-free, but heated air from the cabinet.

Abstract: A vaporization cooled transformer utilizes the vaporized coolant at a constant predetermined pressure for upgrading the dielectric strength of the coolant. An auxiliary heater is employed for vaporizing the coolant at low temperature ambient conditions. The constant predetermined pressure is maintained at higher ambient conditions by controlling the cooling capacity of a plurality of heat exchangers.

Abstract: The present invention preferably comprises a modular air core coil inductance assembly which is comprised of a plurality of spiral windings which are magnetically coupled to each other and disposed in planes which are orthogonal to the longitudinal axis of the resultant air core coil. The modular air core coil assembly may preferably comprise a plurality of air core coil subassemblies each of which preferably comprises at least one spiral winding disposed on a winding support member, with the winding preferably being an electrical conductor wound in the shape of an Archimedes spiral disposed in a plane orthogonal to the longitudinal axis of the coil; a fixing or holding member which is disposed facing the spiral winding in order to set or hold it in position; at least two shields fixed on the coil ends in order to prevent magnetic coupling between the different coils; and at least two spacing members disposed so as to obtain the desired distance between the shield and the winding.

Abstract: A vaporization cooled transformer of the type comprising a transformer tank in combination with a heat exchanger employs temperature sensing means in both the tank and the heat exchanger for sensing a predetermined temperature differential to indicate the presence of air in the transformer. When the temperature differential exceeds a predetermined range, an alarm and a transformer disconnect relay become actuated. The temperature differential sensor can also be calibrated to provide excess moisture indication above a threshold moisture content caused by the saturation of the molecular sieve water scavenger within the transformer assembly.

Abstract: Electrical inductive apparatus cooled by a two-phase dielectric fluid which vaporizes within the normal operating temperature range of the apparatus. The electrical inductive apparatus consists of a sealed enclosure surrounding a magnetic core and electrical winding assembly. A non-condensable gas fills a major portion of the enclosure at no-load conditions to provide adequate dielectric strength around the apparatus and is substantially removed to a storage tank when the apparatus reaches normal operating conditions. The required volume of the storage reservoir is proportional to the free volume of the enclosure and the volume of liquid dielectric disposed therein. The bottom surface of the enclosure includes a recessed channel portion configured to closely surround the lower yoke of the magnetic core and which serves to reduce the amount of liquid dielectric utilized and the free volume of the enclosure thereby minimizing the required volume of the storage reservoir for the non-condensable gas.

Abstract: Electrical apparatus cooled by dielectric fluid which vaporizes within the normal operating temperature range of the electrical apparatus. The electrical apparatus includes a plurality of fluid flow passages extending vertically therethrough which have widths within the range of approximately 0.010 inch to approximately 0.060 inch. The small width of the fluid flow passages causes the dielectric fluid to uniformly coat or wet both wall surfaces of the passages as it flows therethrough.

Abstract: A heat storage system provides overload capacity for a vaporization-cooled electrical apparatus. An external housing, containing a heat storage fluid, is disposed around a fluid conductor connecting a non-condensable gas storage reservoir and the radiator of a vaporization-cooled electrical apparatus. At normal loads, the non-condensable gas is contained within the fluid conductor and the storage reservoir thereby thermally isolating the storage fluid from the hot vapors contained within a radiator which keeps the storage fluid at ambient temperatures. A pressure increase, caused by an overload, compresses the non-condensable gas into the storage reservoir and allows the hot vapors to flow into a portion of the fluid conductor surrounded by the external housing whereby heat is dissipated from the hot vapors to the storage fluid contained within the external housing.

Abstract: Electrical inductive apparatus cooled and electrically insulated by a vaporizable liquid dielectric having a boiling point within the normal operating temperature range of the apparatus. When the electrical inductive apparatus is at ambient temperature, the liquid dielectric completely fills the enclosure providing electrical insulation for the electrical members. As the temperature of the apparatus increases towards its normal operating range, the liquid dielectric is gradually withdrawn into a reservoir until, at the normal operating temperature, only a quantity of liquid dielectric sufficient to completely cover the electrical inductive apparatus remains in the enclosure. In response to a temperature decrease, the liquid stored in the reservoir is gradually returned to the enclosure thereby maintaining a constant level of dielectric strength between the electrical members.

Abstract: A fluid distribution manifold for a vaporization cooled electrical apparatus. The manifold includes a flexible conduit of predetermined shape having a plurality of longitudinal and circumferential spaced apertures therein which distribute a vaporizable dielectric fluid uniformly and economically over the electrical apparatus.

Abstract: Overpressure protection for a vaporization cooled electrical inductive apparatus. A pressure responsive device is actuated by a predetermined pressure within a sealed housing and de-energizes a pump, thereby stopping the flow of dielectric fluid to the heat producing members which prevents further pressure increases within a tank due to continued vaporization of the dielectric fluid. In one embodiment, a discharge valve is actuated by the pressure responsive device to drain the dielectric fluid from the windings to prevent further pressure increases caused by continued vaporization of the dielectric fluid. A fusible link is provided to disconnect the windings of the electrical inductive apparatus from a source of electrical potential subsequent to the de-energization of the pump. In another embodiment, the pressure responsive device actuates the circuit breaker which disconnects the windings of the electrical inductive apparatus from the source of electrical potential.

Abstract: An electrical apparatus having a casing with an electrical conductor disposed therein and a vapor lift pump for applying a vaporizable liquid coolant to the electrical conductor to effect cooling of electrical conductor by vaporization of the applied liquid coolant. A non-condensable gas acts as a padding gas at low temperatures and is circulated through the vapor lift pump from a gaseous inlet. The vaporizable liquid is driven by the non-condensable gas onto the electrical conductor, vaporizes, recondenses on the casing wall and returns to a reservoir where it is again picked up by the non-condensable gas.

Abstract: A transformer having a forced air cooling system is disclosed. The transformer includes an insulating oil which is forcibly moved in the transformer and an insulating sheet which is partially covered with particles, fibers or other forms of an inorganic material for producing a static charge of opposite polarity to the charge produced by the base material of the insulating sheet caused by relative motion due to forced flow of the insulating oil.

Abstract: A device for detecting the level of the molten metal surface within a continuous casting mold. A detector element consisting of a body of a thermosensitive magnetic material, the magnetic properties of which vary in response to a temperature variation, is mounted at an appropriate position on a side wall of the continuous casting mold, and an electromagnetic coil for detecting the magnetic flux in the detector element is contained within a detector box mounted in a water jacket surrounding the mold at a position opposed to the detector element. The molten metal surface level within the mold is detected by detecting a change in the magnetic properties of the detector element by means of the electromagnetic coil. The detector box is detachably mounted in the water jacket, and water supply inlet and outlet means in the detector box guide cooling water through the detector box for cooling the electromagnetic coil within the detector box.

Abstract: A hermetically sealed vaporization chamber contains a vaporization cooled transformer to be cooled while dielectrically protected and two phase dielectric fluid comprising a liquid and a vapor. The transformer includes a plurality of cooling ducts extending vertically therethrough. The liquid, which resides at a bottom portion of the chamber and has a liquid level above the bottom of the chamber, is also distributed as a film which coats the top and the wall surfaces of the vertical ducts. A distribution pan with an outer rim is positioned above the transformer for receiving liquid condensate from said condenser. The rim portion of the distribution pan is provided with a plurality of apertures to distribute the liquid condensate uniformly as a film over the wall surfaces of the associated vertical ducts. At least one condensate make-up pump is provided for pumping liquid from the bottom portion of the chamber to the distribution pan.

Abstract: This invention relates to improvements in systems for force-cooling transformers of the kind in which an outer helical winding and an insulation barrier nested therein form an axially extending annular passage for cooling-fluid flow. In one form of the invention a tubular shroud is positioned about the helical winding to define an axially extending annular chamber for cooling-fluid flow. The chamber has a width in the range of from about 4 to 25 times that of the axially extending passage. Two baffles extend inward from the shroud to define with the helical winding two annular flow channels having hydraulic diameters smaller than that of the chamber. The inlet to the chamber is designed with a hydraulic diameter approximating that of the coolant-entrance end of the above-mentioned annular passage. As so modified, transformers of the kind described can be operated at significantly higher load levels without exceeding safe operating temperatures.

Abstract: A vaporization cooled transformer includes an improved liquid distribution system which distributes the dielectric or cooling liquid in a predetermined fashion for liquid film flow over the wall surfaces of vertical cooling ducts with minimal liquid hold-up.