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IPC classes for russian patent Tubular electric heater (RU 2516006):
Another patents in same IPC classes:
 Tubular electric heater / 2510162
Tubular electric heater comprises a protective metal shell 1 with a flange seal 2 and a connection element 3 for supply of feed voltage, dielectric washers 4, internal and external cylindrical surfaces 5 and 6 are metallised, and flat cylindrical surfaces are coated with a resistive layer 7, with rising resistance in radial direction, the resistive layer 7 has an electric contact with metallisation on the internal cylindrical surface 5 and the external cylindrical surface 6 of washers 4, metallisation on the internal cylindrical surface 5 of washers has electric contact with the internal tubular current lead 8, metallisation on the external cylindrical surface 6 of washers has electric contact with the shell 1. The electric heater is mounted into a reservoir with a heated liquid so that the protective metal shell 1 and the reservoir itself are grounded, which complies with requirements of the Regulations of Electric Installation Design (PUE). When feed voltage is supplied to the connection element 3 from the grid made in accordance with the circuit of dead-earthed neutral, this voltage via the internal tubular current lead 8 becomes applied to the resistive layer 7 of all dielectric washers, where heat release takes place.
Method to seal tubular electric heaters / 2474091
In the method for sealing of tubular electric heaters, in which near-end cavities are filled with a sealing rubber-like material, the sealing rubber-like material is a mixture of an organosilicon vinyl-containing rubber, oligomethylhydridedimethylsiloxane and titanium dioxide, hardened with a solution of a platinum-chloro-hydrogen acid in isopropyl alcohol.
 Electric heating element with thermal switch (versions) / 2400943
Invention relates to electric heating elements intended for equipment of tubular electric heaters (THE) protected against overheating. Four versions of electric heating element design with thermal switch are proposed, where the element comprises heater made of metal wire with high specific electric resistance, in the form of helical spatial spiral, and thermal switch, having thermal link arranged in the form of tube from fusible metal alloy and compensator made of metal wire with high specific electric resistance. In the first version of design thermal switch comprises electric terminal made of metal wire, end of which is connected to end of thermal link, and contact made from metal tube, end of which is partially placed onto other end of thermal link and is connected to it. Compensator of thermal switch is arranged in the form of stepped spatial spiral, narrowed part of which is introduced into other end of contact and is connected to it. Electric terminal is introduced with its other end to end part of heater and is connected to it. In the second version of design thermal link is partially inserted by its one end into end portion of compensator at the side of turns connected to each other and is connected to it, by its other end it is connected to electric terminal. Electric terminal is introduced with its other end to end part of heater and is connected to it. In the third version of design thermal link is partially inserted by its one end into end portion of compensator, and is connected to it, by its other end it is connected to electric terminal end. By its other end electric terminal is introduced into end part of heater and is connected to it. In the fourth version of design thermal link of thermal switch is arranged as closed at one end, other end of thermal link is inserted into end part of compensator and is connected to it. End of heater is placed onto closed end of thermal link and is connected to it.
 Resistance heater of fluid media / 2397621
Invention can be used for heating of various fluids, gases or fine powders in processes, heating systems, hot water supply systems of domestic compartments, industrial premises, etc. Heater of fluid media includes the cover having inner cavity in which there located with a gap is spiral from electrically conducting material with possibility of being connected to voltage source, and the above gap is filled with electrically insulating heat conducting material, at least one heating element the cover of which and the spiral located in its cavity are flat; at that, it is provided with transport means of heated fluid medium through heater, which has input and output and made so that when heated fluid medium passes through it, it contacts the external surface of flat cover.
 Heat-resistant cable with alternation of "cold" and "hot" zones (three versions) / 2388189
Invention relates to cable items intended for use mainly in nuclear power engineering. According to the first version, cable consists of metal heat-resistant corrosion-resistant shell filled with mineral insulation and also of current conductor installed coaxially inside shell. Conductor is made of current-conducting material with high specific electric resistance and has various diametre in "cold" and "hit" zones, besides transfer from one zone to the other one is arranged as stepped. In cable according to the second version conductor is arranged as combined, with application of bimetal in zones with lower electric resistance. In cable according to the third version conductor is made as combined, with application of bimetal in "cold" zones, and with various diametre of current conductor in "cold" and "hot" zones, besides transfer from one zone to another one is arranged as stepped.
 Heating coil with protection against primary scale (versions) / 2385552
Invention has a property to prevent formation of salt deposits (scale) on its shell, in process of water heating and boiling. Heating coil may be used to produce various electric water heaters using heating coils. Heating coil with its own protection against primary scale comprises heating element in the form of bent spiral, ends of which are connected to contact rods, pressed together with them and filler into ferromagnetic shell, sealed at the ends, and equipped with electric insulators and elements of fixation to water heater body at the ends, and generator of magnetic field, such as spiral of heating element, specified spiral of heating element is arranged of at least two adjacent identical sections, adjacent sections of spiral have opposite directions of winding. In other version adjacent sections have identical directions of winding and are separated from each other by means of rectilinear or zigzag-bent section made of the same conductor as spiral. Inside turns of each section there is a ferromagnetic rectilinear rod inserted.
 Manufacturing method of tubular electric heating unit / 2371887
Metal tube (1) is out on metallic string, to bottom end of which there are connected leads of spiral of heating element (4). To the middle of spiral it is suspended hook end with chuck. It is pulled down tube (1) on spiral and fixed on chuck. Tube (1) with spiral is unhooked from string, is installed into spring-loaded funnel of charging equipment. There are fixed in installation leads (5) spirals are put on branched of spiral two bushings, through which it is filled electro-insulating filler. As far as filling by filler (3) tubes (1), of cartridge case from it is lead out. Filled tube (1) is pressed and fixed to it bottom (2).
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Manufacturing method of tubular electric heating unit / 2371887
Metal tube (1) is out on metallic string, to bottom end of which there are connected leads of spiral of heating element (4). To the middle of spiral it is suspended hook end with chuck. It is pulled down tube (1) on spiral and fixed on chuck. Tube (1) with spiral is unhooked from string, is installed into spring-loaded funnel of charging equipment. There are fixed in installation leads (5) spirals are put on branched of spiral two bushings, through which it is filled electro-insulating filler. As far as filling by filler (3) tubes (1), of cartridge case from it is lead out. Filled tube (1) is pressed and fixed to it bottom (2).
Heating coil with protection against primary scale (versions) / 2385552
Invention has a property to prevent formation of salt deposits (scale) on its shell, in process of water heating and boiling. Heating coil may be used to produce various electric water heaters using heating coils. Heating coil with its own protection against primary scale comprises heating element in the form of bent spiral, ends of which are connected to contact rods, pressed together with them and filler into ferromagnetic shell, sealed at the ends, and equipped with electric insulators and elements of fixation to water heater body at the ends, and generator of magnetic field, such as spiral of heating element, specified spiral of heating element is arranged of at least two adjacent identical sections, adjacent sections of spiral have opposite directions of winding. In other version adjacent sections have identical directions of winding and are separated from each other by means of rectilinear or zigzag-bent section made of the same conductor as spiral. Inside turns of each section there is a ferromagnetic rectilinear rod inserted.
Heat-resistant cable with alternation of "cold" and "hot" zones (three versions) / 2388189
Invention relates to cable items intended for use mainly in nuclear power engineering. According to the first version, cable consists of metal heat-resistant corrosion-resistant shell filled with mineral insulation and also of current conductor installed coaxially inside shell. Conductor is made of current-conducting material with high specific electric resistance and has various diametre in "cold" and "hit" zones, besides transfer from one zone to the other one is arranged as stepped. In cable according to the second version conductor is arranged as combined, with application of bimetal in zones with lower electric resistance. In cable according to the third version conductor is made as combined, with application of bimetal in "cold" zones, and with various diametre of current conductor in "cold" and "hot" zones, besides transfer from one zone to another one is arranged as stepped.
Resistance heater of fluid media / 2397621
Invention can be used for heating of various fluids, gases or fine powders in processes, heating systems, hot water supply systems of domestic compartments, industrial premises, etc. Heater of fluid media includes the cover having inner cavity in which there located with a gap is spiral from electrically conducting material with possibility of being connected to voltage source, and the above gap is filled with electrically insulating heat conducting material, at least one heating element the cover of which and the spiral located in its cavity are flat; at that, it is provided with transport means of heated fluid medium through heater, which has input and output and made so that when heated fluid medium passes through it, it contacts the external surface of flat cover.
Electric heating element with thermal switch (versions) / 2400943
Invention relates to electric heating elements intended for equipment of tubular electric heaters (THE) protected against overheating. Four versions of electric heating element design with thermal switch are proposed, where the element comprises heater made of metal wire with high specific electric resistance, in the form of helical spatial spiral, and thermal switch, having thermal link arranged in the form of tube from fusible metal alloy and compensator made of metal wire with high specific electric resistance. In the first version of design thermal switch comprises electric terminal made of metal wire, end of which is connected to end of thermal link, and contact made from metal tube, end of which is partially placed onto other end of thermal link and is connected to it. Compensator of thermal switch is arranged in the form of stepped spatial spiral, narrowed part of which is introduced into other end of contact and is connected to it. Electric terminal is introduced with its other end to end part of heater and is connected to it. In the second version of design thermal link is partially inserted by its one end into end portion of compensator at the side of turns connected to each other and is connected to it, by its other end it is connected to electric terminal. Electric terminal is introduced with its other end to end part of heater and is connected to it. In the third version of design thermal link is partially inserted by its one end into end portion of compensator, and is connected to it, by its other end it is connected to electric terminal end. By its other end electric terminal is introduced into end part of heater and is connected to it. In the fourth version of design thermal link of thermal switch is arranged as closed at one end, other end of thermal link is inserted into end part of compensator and is connected to it. End of heater is placed onto closed end of thermal link and is connected to it.
Method to seal tubular electric heaters / 2474091
In the method for sealing of tubular electric heaters, in which near-end cavities are filled with a sealing rubber-like material, the sealing rubber-like material is a mixture of an organosilicon vinyl-containing rubber, oligomethylhydridedimethylsiloxane and titanium dioxide, hardened with a solution of a platinum-chloro-hydrogen acid in isopropyl alcohol.
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FIELD: electricity.
SUBSTANCE: tubular electric heater contains a heat-producing element 1, for example in a form of a current-conducting spiral placed inside a protective metal shell 2 with an external circumferential finning 3, at the ends of the metal shell 2 there are sealed current leads 4 connected to the outputs of the current-conducting spiral, porous ceramic beads 5 of a tear-drop shape with the heat-producing element 1 placed in their internal opening, along their perimeter the beads are covered by the protective metal shell 2, the porous ceramic beads have width variable by height thus covering the heat-producing element completely or covering it minimally in the upper part, the inner cavity of the tubular electric heater, including pores of the ceramic beads, is filled with liquid partially. When voltage is supplied to the current leads 4 connected to the outputs of the current-conducting spiral the temperature of the spiral is increased as far as heat conductivity of the porous ceramic beads 5 is low, heating of the spiral of the heat-producing element 1 takes place fast, nevertheless the temperature of the protective shell 2 and finning 3 is defined by the temperature of the external heat carrier. As far as the inner cavity of the heater and pores of the beads are filled with liquid at certain temperature this liquid boils, steal comes through the pores to the space between the porous beads 5, where it is condensed at the inner surface of the protective shell 2 giving it the accumulated evaporation heat. The condensed steam in the form of liquid comes to the surface of the porous beads 5 and due to capillary action it is saturated inside into the beads 5 coming down to the heated spiral, there it boils again thus accumulating evaporation heat and closing the cycle of heat transfer and circulation loop.
EFFECT: improving operating reliability.
2 dwg
The invention relates to electrical engineering, in particular, to devices convert electrical energy into thermal energy, made in the form of straight or curved tubular elements used, in particular, in the construction of thermocompressors, providing the necessary pressure in the brine circuit of a nuclear power plant.
Known tubular heater classic designs containing fuel element in the form of conductive spiral of heat-resistant material, placed inside a protective metal sheath, and between the fuel element and the protective sheath is a layer of insulating material, usually in the form of powder filling magnesium oxide, on the ends of the metal shell is made sealed current leads (US Patent No. 7,019,269 B2, IPC NV 3/44, publ. 28.03.2006 g).
A disadvantage of the known construction is that between the fuel element and the heat-release surface protective shell need a layer of insulation, ensuring the electrical safety of the heater and preventing the emergence of inter-turn short circuits the heating coil. This layer, performing a useful function of insulation, makes thermal resistance in the path of heat transfer from the fuel elements to the surface of the heat exchange with the outside is teplonositelem, which is especially noticeable when using powder electrical insulating materials. The presence of this thermal resistance leads to the fact that to achieve a significant density of the heat flux on the surface of the heat transfer necessary to repeatedly increase the temperature of the heating coil inside the tubular heater, which reduces the service life of the heater.
The closest in technical essence is a tubular heater containing fuel element in the form of conductive spiral located inside a protective metal shell having an external transverse ribbing on the ends of the metal shell is made of a sealed power supply circuit (RF Patent No. 2120199, IPC NV 3/48, publ. 10.10.1998 g).
Known tubular heater has the same disadvantages heaters of conventional design, namely, low resource and operational reliability associated with the presence of thermal resistance vinyl interlayer and overheating of the fuel element. For example, in a tubular electric heaters running in thermocompressors NPP when the ambient temperature of 300-350°C, the temperature of the spiral approaching 900°Stacy temperature creates two negative factor. First, destroyed the structure of the material of the heating coil with a capacity which allows it to burn out. Secondly, at high temperatures can degrade the insulating properties of the backfill, it appears channels electrical breakdown, destroying the outer protective shell. The ingress of water through the fistula formed inside the heater causing steam explosions, completely destroying the heater. Both of these factors reduce the resource and the operational reliability of the tubular heater.
Technical problem solved by this invention is the enhancement of life and operational reliability of tubular heater
The technical result consists in increasing thermal conductivity in the direction from the fuel elements to the surface of heat exchange with an external fluid is achieved by the fact that in the known tubular heater containing heat-generating element, for example, in the form of a conductive helix, located inside a protective metal shell having an external transverse ribbing on the ends of the metal shell is made sealed leads entered porous dielectric spacers having cablevideo form, in the inner hole which is placed a fuel element, and the external contour of washers are enclosed in a protective metal sheath, porous ceramic washers have a variable height thickness from fully zakrya the soup the fuel element to a minimum in the upper part, the internal cavity of the tubular heater, including the pores of the ceramic washers, partially filled with fluid.
The invention is illustrated by drawings, where figure 1 shows a General view of the tubular heater with slit revealing the internal structure of the heater; figure 2 shows the front view and the side view of the porous dielectric washer.
Tubular heater provides heat-generating element 1, for example, in the form of a conductive helix, located inside a protective metal shell 2 having an external transverse fins 3, at the ends of the metal shell is made of a sealed power supply circuit 4, is attached to the conclusions of the spiral conductive, porous ceramic (dielectric) washer 5 with cablevideo form, in the inner hole which is placed a fuel element 1 and the external contour of washers are enclosed in a protective metal sheath 2, the porous ceramic washers have a variable height thickness from fully closing the fuel element 1 to a minimum in the upper part, the inner cavity of the tubular heater including the pores of the ceramic washers partially filled with liquid
Tubular heater works as follows.
When voltage is applied to the current leads 4 connected to the output of the m conductive spiral its temperature increases since thermal conductivity of porous ceramic washers 5 is small, the heating spiral heat-generating element 1 is fast, but the temperature of the protective sheath 2 and the fins 3 is determined by the temperature of the external coolant. Since the internal cavity of the tubular heater and the pores of the ceramic washers filled with liquid, e.g. water, at a certain temperature the liquid boils, the vapor through the pores into the space between the porous washers 5 where it condenses on the inner surface of the protective shell 2, giving her the stored heat of vaporization. The condensed vapor and the liquid falls to the surface of the porous spacers 5 and due to the effect of capillarity absorbed into the washers 5, falling to the heated spiral, where again begins to boil, reserving the heat of vaporization and closing, thus, the cycle of heat transfer and circuit. Thus, the process of heat transfer from the heating element to the outer surface of the tubular heater is not due to the conductivity of the powder layer of insulation, and due to the circulation of the internal fluid undergoing a phase transition.
This mechanism of heat transfer is fully consistent with the processes inside the so-called heat pipes, experimental study which gives a record is a simple conductivity, more than three orders of magnitude greater than thermal conductivity of most heat-conducting substances. Due to the record heat conduction the temperature of the heated end of the heat pipe and cooled differ by several tenths of a degree. For tubular heater this means that after the regime of two-phase heat transfer, the temperature of the heating element is determined by the temperature of the external coolant with a slight excess of determining the heat flux density. This excess is usually at 50°C. For tubular heaters, working as part of thermocompressor nuclear power plant and providing external heating of the heat carrier to a temperature of 300-350°C, increasing thermal conductivity inside the heater allows to reduce the temperature of the heating element 1 to values not exceeding 400°C. Such conditions do not lead to destruction of the heating element and the porous ceramic washers that allows you to increase the service life and operational reliability of the tubular heater.
Since the internal cavity of the tubular heater is closed, when the boiling of the liquid inside the protective sheath 2, the pressure in the cavity increases and can reach considerable values, depending on the temperature of the external coolant. In this regard, the outer lateral fins except Uwe is icene heat exchange surface performs the function of increasing the mechanical strength of the protective shell 2.
As an internal coolant can be used water, freon, liquid hydrocarbons and other liquids, the choice of which is determined by the temperature and power modes of the tubular heater.
The use of the invention increases service life and operational reliability of tubular heater due to the introduction of the described structural elements, providing a significant increase in thermal conductivity from the heat-generating element to the external heat transfer surface.
Tubular heater containing fuel element located inside a protective metal shell having an external transverse ribbing on the ends of the metal shell is made sealed current leads attached to the conclusions of the conductive helix, characterized in that it introduced the porous ceramic washer having a tear drop shape, in the inner hole which is placed a fuel element, and the external contour of washers are enclosed in a protective metal sheath, porous ceramic washers have a variable height thickness from fully closing the fuel element to a minimum in the upper part, the inner cavity of the tubular heater, including the pores of the ceramic washers, partially filled LM is bone.
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