Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/06—Spray pistols; Apparatus for discharge with at least one outlet orifice surrounding another approximately in the same plane
  • B05B7/062—Spray pistols; Apparatus for discharge with at least one outlet orifice surrounding another approximately in the same plane with only one liquid outlet and at least one gas outlet
  • B05B7/066—Spray pistols; Apparatus for discharge with at least one outlet orifice surrounding another approximately in the same plane with only one liquid outlet and at least one gas outlet with an inner liquid outlet surrounded by at least one annular gas outlet
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
  • C21D1/62—Quenching devices
  • C21D1/667—Quenching devices for spray quenching
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
  • B05B1/26—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/04—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge
  • B05B7/0416—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid
  • B05B7/0441—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid with one inner conduit of liquid surrounded by an external conduit of gas upstream the mixing chamber
  • B05B7/045—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid with one inner conduit of liquid surrounded by an external conduit of gas upstream the mixing chamber the gas and liquid flows being parallel just upstream the mixing chamber
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/08—Spray pistols; Apparatus for discharge with separate outlet orifices, e.g. to form parallel jets, i.e. the axis of the jets being parallel, to form intersecting jets, i.e. the axis of the jets converging but not necessarily intersecting at a point
  • B05B7/0807—Spray pistols; Apparatus for discharge with separate outlet orifices, e.g. to form parallel jets, i.e. the axis of the jets being parallel, to form intersecting jets, i.e. the axis of the jets converging but not necessarily intersecting at a point to form intersecting jets
  • B05B7/0846—Spray pistols; Apparatus for discharge with separate outlet orifices, e.g. to form parallel jets, i.e. the axis of the jets being parallel, to form intersecting jets, i.e. the axis of the jets converging but not necessarily intersecting at a point to form intersecting jets with jets being only jets constituted by a liquid or a mixture containing a liquid
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B27/00—Tempering or quenching glass products
  • C03B27/02—Tempering or quenching glass products using liquid
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B27/00—Tempering or quenching glass products
  • C03B27/02—Tempering or quenching glass products using liquid
  • C03B27/022—Tempering or quenching glass products using liquid the liquid being organic, e.g. an oil
  • C03B27/024—Tempering or quenching glass products using liquid the liquid being organic, e.g. an oil the liquid being sprayed on the object
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B27/00—Tempering or quenching glass products
  • C03B27/02—Tempering or quenching glass products using liquid
  • C03B27/028—Tempering or quenching glass products using liquid the liquid being water-based

Definitions

• the invention relates to a method according to the preamble of claim 1 for tempering material and to apparatus according to the preamble of claim 16 for tempering material.
• the aim with the tempering is a specific, predetermined martensite content in the microstructure of the tempered piece.
• Glass tempering aims at using rapid cooling to produce a compression tension in the surface layer of the glass and a tensile stress into the inner part of the glass.
• a problem with the above prior art solution based on air cooling is that air cooling in connection with tempering requires an extremely large amount of air and an efficient blow thereof towards the surface of the material or product to be tempered. Such a large amount of air and efficient blow consume extremely high amounts of energy. Moreover, in many applications management of rapid and uniform cooling is difficult to control and carry out, particularly when thin pieces, such as thin glass, are being tempered. Hence air cooling and the control thereof for producing an even cooling requires complex hardware solutions. Water tempering, in which a hot piece is immersed into water, is impossible to control on an industrial scale when tempered products of a good quality are to be produced.
• the object of the invention is achieved by a method according to the characterizing part of claim 1 , characterized in that in the method at least one liquid is atomized into droplets, the formed droplets being guided towards a surface of a hot material so that at least some of the droplets collide with the surface of the hot material and evaporate when they receive thermal energy from the surface layer of the hot material.
• the object of the invention is further achieved by the apparatus according to the characterising part of claim 16, the apparatus being characterized in that the apparatus comprises one or more sprayers for atomizing at least one liquid into droplets and means for guiding the formed droplets towards a surface of a hot material so that at least some of the droplets collide with the surface of the hot material and evaporate, thus removing thermal energy from the surface layer of the hot material.
• the invention is based on the idea of cooling a material or product in tempering by using at least one liquid which is atomized into small droplets by means of one or more sprayers.
• the droplets are further conveyed to the surface of the hot material to be tempered so that the droplets collide with the surface of the hot material to be tempered.
• the droplets may be guided towards the surface of the hot material by using a gas flow, the cooling of the hot material being achieved by an aerosol that comprises the formed droplets.
• the droplets colliding with the hot surface of the material receive thermal energy from the hot material and evaporate quickly.
• a droplet collides with the surface of the hot material, it evaporates in the collision or immediately thereafter. This is achieved by using sufficiently small droplets.
• the liquid is preferably coalesced into droplets having an average diameter smaller than or equal to 30 ⁇ m. These extremely small droplets evaporate rapidly as they collide with the hot material, thus removing efficiently thermal energy from the hot material.
• the power of the collision on the surface of the hot material is sufficiently efficient for evaporating small droplets substantially in connection with the collision.
• An advantage of the method and apparatus of the invention is that the use of small droplets for cooling hot material in a tempering process enables an energy efficient means for tempering a hot material.
• the small droplets allow a rapid and efficient heat transfer from a hot piece to be achieved. Uniform and rapid heat transfer is particularly important when large surfaces and thin products, such as thin glass, are to be tempered. Cooling produced with small droplets consumes significantly less energy than prior art air cooling and, moreover, a tempering apparatus based on the use of small droplets has a structure that is simpler to produce.
• Figure 1 is a schematic view of the apparatus according to the invention for tempering material
• Figure 2 is a schematic view of a sprayer for carrying out tempering according to the invention
• Figure 3 is a schematic view of a second sprayer for carrying out tempering according to the invention.
• Figure 4 is a schematic view of a second embodiment of the sprayer.
• FIG. 1 discloses an embodiment of the apparatus of the invention that allows the method of the invention to be implemented.
• the apparatus 50 is used for tempering a moving hot material web 26.
• the material to be tempered may be for example metal, such as steel, glass, metal alloy or a ceramic material.
• Figure 1 shows the tempering of a moving material web
• the method and apparatus of the invention may be applied to the tempering of any material or product movable in any way.
• the material or product to be tempered may also be stationary and one or more sprayers may move.
• the apparatus 50 comprises a sprayer 22 that allows the one or more liquids to be atomized into small droplets.
• the apparatus 50 may also comprise two or more sprayers 22.
• the liquid to be atomized with the sprayer 22 to be used in tempering is preferably water, although it may also be an alcohol, such as a mixture of ethanol, water and alcohol, or some other liquid mixture or emulsion comprising water and/or alcohol. Alternatively, it is also possible to use some other liquid suitable for cooling or tempering or a mixture of one or more liquids.
• the liquid to be atomized is conveyed to the sprayer 22 on a line 2 through a flow meter 27. Also a gas flow is conveyed to the sprayer 22 on a channel 20 and through a flow regulator 18.
• the sprayer 22 shown here is a gas dispersing sprayer, although an ultrasound sprayer or some other sprayer capable of producing sufficiently small droplets is also possible.
• the sprayer 22 atomizes liquid into small droplets 7 which are led by means of the gas flow, for example, towards the surface of the material web 26 to be tempered.
• the sprayer 22 may be in a chamber 14, which substantially separates the inner space of chamber 14 from the ambient atmosphere.
• Inert gas for example, may be supplied into the chamber 14 from a gas conduit, which is preferably the gas conduit 20 used for atomizing the liquid.
• gas may be supplied into the chamber 14 from separate gas nozzles.
• the chamber 14 may also be provided with suction means for removing evaporated droplets 7 from the chamber 14.
• the apparatus 50 comprises means for guiding droplets 7 formed with the sprayer 22 towards the surface of the hot material 26. These means for guiding the formed droplets 7 towards the surface of the hot material may comprise one or more gas flows 20 atomizing at least one liquid, or one or more separate gas nozzles (not shown).
• the heating of the material to be tempered may take place in process step 24, for example, which is arranged upstream of the sprayer 22 and may consist of heating, working or a similar process step.
• the tempering apparatus 50 of the invention is connected to a manufacturing or processing line of a material or product, such as a flat glass manufacturing line, the manufacturing line of some other glass product, the manufacturing line of steel or to the manufacturing or processing line of some other product or material.
• the tempering apparatus 50 may be placed after the tin bath in the float line, for example, the temperature of the glass strip rising from the bath being 650 0 C at the most.
• the temperature of the hot material arriving at the tempering may be from 850 to 450 0 C, for example. However, the temperature depends on the material to be tempered and the desired tempering properties.
• hot material is tempered using small droplets 7 to produce the necessary rapid cooling, the droplets being guided to collide with the surface of the hot material 26 so that the droplets 7 collide with the surface of the hot material 26, as shown in Figure 1.
• Sufficiently small size of the droplets 7 allows them to be made to collide with the surface of the hot material 26 at a sufficient speed.
• the droplets 7 receive thermal energy from the material 26, particularly from the surface layer thereof, and evaporate. To create efficient and rapid cooling the droplets 7 need to be sufficiently small.
• one or more sprayers 22 are arranged to atomize at least one liquid into droplets with an average diameter smaller than or equal to 30 ⁇ m, preferably smaller than or equal to 10 ⁇ m and more preferably smaller than or equal to 5 ⁇ m.
• the sprayer 22 has been achieved by producing droplets 7 with an average diameter of less than 3 ⁇ m, and preferably even droplets 7 of an average diameter of less than 1 ⁇ m. If the droplets 7 are too big, for example 100 ⁇ m or more, the droplets 7 do not evaporate rapidly enough when they collide with the surface of the hot material 26 but form a liquid film onto the surface of the hot material 26, or remain floating onto the surface of the hot material 26.
• the small droplets 7 may be generated using a gas dispersing sprayer 22 or an ultrasound sprayer, for example.
• a disadvantage with the ultrasound sprayer is its low droplet production rate and the need for a separate control gas for guiding the droplets 7 towards the surface of the hot material 26.
• the droplets are to be sufficiently small in order to have a sufficiently small mass for a rapid evaporation and, moreover, the droplets are to be guided towards the surface of the hot material at a sufficient rate for an efficient collision to be achieved.
• the small size of the droplets 7 and their sufficient speed causes the droplets 7 to collide substantially as separate droplets, thereby avoiding the formation of a liquid film or pools onto the surface of the hot material.
• the sufficient speed of the droplets 7 depends for example on the size of the droplets 7 and on the liquid used for the cooling and for forming the droplets 7.
• the following shows by means of Figures 2, 3, and 4 examples of alternative sprayers 22, with which sufficiently small droplets 7 may be produced.
• FIG. 2 shows a basic view of the sprayer 22.
• Liquid such as water, used in tempering is fed into the sprayer producing ultra-small liquid droplets from a channel 25.
• Spraying gas such as nitrogen N 2 , is led to a gas channel 20.
• a distributing chamber 30 and flow impediments 32 distribute the spray flow evenly around the liquid channel 25, whereby the liquid atomizes into droplets in the spray nozzle 34.
• the droplet size of the aerosol atomized in the spray nozzle 34, or spray head 34 is relatively large.
• the flow impediments 36 alter the hydrodynamic properties of the aerosol flow and unexpectedly cause the droplet size of the aerosol to change into ultra-small droplets.
• the mechanism is based on both collision energy and pressure change caused by the flow impediments 36.
• the flow impediments 36 are arranged in such a manner that the droplets of the aerosol discharging from the spray head 34 collide into one or more flow impediments 36 and/or each other to reduce the droplet size of the aerosol.
• the flow impediments 36 are arranged in such a manner that they generate into the aerosol flow discharging from the spray head 34 a pressure change and/or restriction to reduce the droplet size of the aerosol.
• ultra-small droplets 7 discharge from the nozzle.
• the ultra-small droplets are further directed to the surface of the hot material 26.
• the droplets 7 evaporate as they collide with the surface of the hot material 26 and remove heat energy from the hot material 26.
• the sprayer 22 of Figure 2 atomizes at least one liquid into aerosol at the spray head 24 of the sprayer 22 by means of gas.
• the sprayer 22 has at least one liquid channel 25 for supplying at least one liquid to be atomized into the spray head 34 and at least one gas channel 20 for supplying at least one gas into the spray head 34 for spraying the liquid into an aerosol.
• the spraying gas atomizes the liquid into an aerosol in the spray head 34 especially as a result of the difference in the velocity of the spraying gas and liquid discharging from the spray head 34.
• the sprayer 22 also comprises one or more flow impediments 36 for altering the hydrodynamic properties, such as velocity and pressure, of the aerosol flow discharging from the spray head 34 in such a manner that the droplet size of the aerosol diminishes.
• the sprayer 22 may be equipped with a spray chamber 35 in flow connection with the spray head 34, to which spray chamber the flow impediments 36 are formed.
• the spray chamber 36 is a tubular space, but may also be some other space.
• the flow impediments 36 may for instance guide, slow, or restrict the aerosol flow.
• the flow impediments 36 are provided on the inner walls of the spray chamber 34 in such a manner that they extend from the inner walls toward the inside of the spray chamber 34.
• the flow impediments 36 are arranged in such a manner that the aerosol droplets discharging from the spray head 34 collide into one or more flow impediments 36 and/or each other to reduce the droplet size of the droplet spray.
• the flow impediments 36 are arranged to generate a pressure change and/or restriction in the aerosol flow discharging from the spray head 34 to reduce the droplet size of the droplet spray.
• the average aerodynamic diameter of the aerosol droplets discharging from the sprayer 22 becomes 10 micrometers, preferably 3 micrometers or less, and more preferably 1 micrometer or less.
• FIG 3 shows another sprayer 22 for generating small droplets.
• Two sprayers 2 directed substantially at each other are fastened to the body 1 of the sprayer 22.
• the sprayers 2 are arranged into the device directly toward each other as shown in Figure 1.
• the sprayers 2 are preferably arranged essentially coaxially opposite each other in such a manner that their droplet sprays 4 essentially directly collide with each other.
• the device may comprise two or more sprayers 2.
• the sprayers 2 are arranged in pairs to form one or more sprayer pairs in such a manner that the sprayers 2 of each sprayer pair are directed essentially directly, preferably coaxially, toward each other, whereby the droplet sprays 4 or each sprayer pair collide directly with each other.
• the sprayer pairs may further be arranged into the device for example consecutively or side by side in the vertical or horizontal direction.
• a liquid 3 to be sprayed and spraying gas 8 are fed into the sprayer 2.
• the spraying gas 8 and liquid 3 are preferably fed into the sprayer 2 at different velocities, whereby the difference in velocity between the spraying gas 8 and liquid 3 at the output of the sprayer 2 cause the liquid 3 to spray, atomize, into a droplet spray 4 that consists of small droplets.
• the droplet sprays 4 collide with each other, whereby an aerosol consisting of very small droplets 7 is unexpectedly formed.
• the droplet spray 4 may in itself already form an aerosol. As droplet sprays directed essentially directly at each other collide, an aerosol is produced that does not essentially move, when the mo- mentums of the droplet sprays 4 are essentially equal.
• the device may further be arranged to contain means for supplying at least two different liquids to at least two sprayers.
• the device may be formed in such a manner that the same or different liquids may be supplied to two or more sprayers 2.
• the same or different liquids may be supplied to the sprayers 2 of each sprayer pair, if desired.
• the same liquid as or different liquids than in the other sprayer pairs can be used in at least two sprayer pairs.
• each sprayer pair may produce a different spray or a similar spray as the sprayer pair beside it.
• the sprayers 2 of the device may be adapted to produce droplet sprays 4 in which the droplets are substantially different or similar in their average droplet size.
• the geometry of the sprayers 2 or the velocity of the fluid 3 and spraying gas or the difference in velocity between them may all affect the size of the droplets. This makes it possible to produce an aerosol that is homogeneous or heterogeneous in droplet size.
• the sprayer 22 preferably also comprises means for directing a gas flow from at least one direction to the collision point of the droplet sprays 4. This is preferably done by furnishing the device with a gas nozzle 5 for supplying gas from at least one direction to the collision point of the droplet sprays 4.
• a gas nozzle 5 for supplying gas from at least one direction to the collision point of the droplet sprays 4.
• Any gas may be used in the gas nozzle 5.
• it may be an inert gas, such as nitrogen, or a gas that reacts to the spray or aerosol.
• the gas nozzle 5 is arranged into the device in such a manner that the gas flow flows and collides substantially perpendicularly in relation to the droplet sprays 4.
• FIG. 4 Another embodiment of the sprayer 22 of Figure 3 is shown in Figure 4.
• Two sprayers 2 directed substantially at each other are mounted on the body 1 of the sprayer 22.
• a liquid 3 to be sprayed and spraying gas 8 are supplied to the sprayer,2.
• the difference in velocity between the spraying gas 8 and liquid 3 at the output of the sprayer 2 makes the liquid 3 atomize into droplet sprays 4 that comprise small droplets.
• the droplet sprays 4 collide with each other, whereby an aerosol made up of very small droplets 7 is unexpectedly formed.
• a liquid 10 and atomizing gas 11 (together: aerosol) are also supplied to the collision point of the droplet sprays 4.
• the atomizing gas 11 then acts as a spraying gas for the liquid 10.
• the aerosol discharging from the sprayer 12 guides the formed droplets on toward the surface of the hot material 26.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Thermal Sciences (AREA)
• Physics & Mathematics (AREA)
• Organic Chemistry (AREA)
• Crystallography & Structural Chemistry (AREA)
• Metallurgy (AREA)
• Mechanical Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Nozzles (AREA)
• Heat Treatments In General, Especially Conveying And Cooling (AREA)
• Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
• Furnace Details (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=40825398

Family Applications (1)

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• 2009
  • 2009-06-18 FI FI20095695A patent/FI125490B/fi not_active IP Right Cessation
• 2010
  • 2010-06-15 TW TW099119402A patent/TW201105914A/zh unknown
  • 2010-06-15 JP JP2012515529A patent/JP2012530189A/ja active Pending
  • 2010-06-15 EP EP10754961A patent/EP2443262A1/en not_active Withdrawn
  • 2010-06-15 WO PCT/FI2010/050499 patent/WO2011004061A1/en active Application Filing
  • 2010-06-15 US US13/320,795 patent/US20120060536A1/en not_active Abandoned
  • 2010-06-15 CN CN201080026724.3A patent/CN102803520B/zh not_active Expired - Fee Related

Non-Patent Citations (1)

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