WO2015086119A1 - Method and apparatus to isolate the cold in cryogenic equipment - Google Patents

Method and apparatus to isolate the cold in cryogenic equipment Download PDF

Info

Publication number
WO2015086119A1
WO2015086119A1 PCT/EP2014/003185 EP2014003185W WO2015086119A1 WO 2015086119 A1 WO2015086119 A1 WO 2015086119A1 EP 2014003185 W EP2014003185 W EP 2014003185W WO 2015086119 A1 WO2015086119 A1 WO 2015086119A1
Authority
WO
WIPO (PCT)
Prior art keywords
shroud
work piece
opening
cover
gas
Prior art date
Application number
PCT/EP2014/003185
Other languages
French (fr)
Inventor
Akin Malas
Peter Christoforou
Original Assignee
Linde Aktiengesellschaft
Siemens Vai Metals Technologies Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Linde Aktiengesellschaft, Siemens Vai Metals Technologies Gmbh filed Critical Linde Aktiengesellschaft
Priority to EP14803052.1A priority Critical patent/EP3079841B1/en
Priority to BR112016013035A priority patent/BR112016013035A2/en
Priority to JP2016538089A priority patent/JP6516745B2/en
Priority to CN201480067528.9A priority patent/CN106163683B/en
Priority to ES14803052.1T priority patent/ES2687785T3/en
Priority to KR1020167018294A priority patent/KR20160096165A/en
Priority to US15/101,484 priority patent/US20160303626A1/en
Publication of WO2015086119A1 publication Critical patent/WO2015086119A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/06—Lubricating, cooling or heating rolls
    • B21B27/10—Lubricating, cooling or heating rolls externally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
    • B21B2003/001—Aluminium or its alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/06—Lubricating, cooling or heating rolls
    • B21B27/10—Lubricating, cooling or heating rolls externally
    • B21B2027/103—Lubricating, cooling or heating rolls externally cooling externally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
    • B21B45/0203—Cooling
    • B21B45/0209—Cooling devices, e.g. using gaseous coolants
    • B21B2045/0212—Cooling devices, e.g. using gaseous coolants using gaseous coolants
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2203/00—Auxiliary arrangements, devices or methods in combination with rolling mills or rolling methods
    • B21B2203/12—Covers or shieldings

Definitions

  • the invention relates to an apparatus for spraying a cryogenic fluid to a work piece comprising a cryogen feed line, at least one delivery nozzle for delivering the cryogenic fluid, a shroud which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece, said shroud and said work piece being movable relative to each other between a working configuration and a maintenance configuration, wherein in said maintenance configuration the front face of the shroud is not completely closed or covered by the work piece, said shroud being arranged to form an essentially closed space together with the work piece in said working configuration.
  • the invention further relates to a method for spraying a cryogenic fluid to a work piece wherein said cryogenic fluid is sprayed by means of at least one delivery nozzle, and wherein a shroud is provided which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece, and wherein said shroud and said workpiece can be arranged in a working configuration wherein said shroud forms an essentially closed space together with said work piece, and wherein said shroud and said workpiece can be arranged in a maintenance configuration wherein said opening of said shroud is not sealed by the work piece.
  • cryogenic fluids for cooling in some metal rolling processes such as the cold rolling of aluminium
  • moisture from the surrounding atmosphere can condense onto the equipment and form water, ice or snow which can then fall or be carried onto the strip and damage it.
  • WO 2012/1 10241 A1 proposes to provide a shroud which surrounds at least part of the delivery nozzle for spraying the cryogenic fluid.
  • the shroud is arranged to form an essentially closed space together with the work piece and it comprises means for keeping the outside of said shielding means at a temperature above the dew point.
  • the shroud and the work piece are arranged close to each other and an essentially closed space is formed which prevents atmospheric air from entering the area within the shroud.
  • An object of this invention is to avoid getting any water into the shroud when it has been retracted from the work piece.
  • Another object of the invention is to avoid getting moisture into the shroud while the shroud is being retracted from the work piece.
  • Another object of the invention is to prevent water droplets from staining the work piece. At least some of these objects are achieved by an apparatus for spraying a cryogenic fluid to a work piece comprising
  • said shroud being arranged to form an essentially closed space together with the work piece in said working configuration
  • said shroud comprises a barrier which prevents or minimizes ambient air from entering the shroud shroud and wherein said barrier comprises one or more physical covers which can be arranged to cover said opening.
  • said opening is sealed by means of a barrier which prevents or minimizes ambient air from entering the shroud, wherein said barrier comprises one or more covers which are arranged to cover said opening in said maintenance configuration.
  • a cryogenic fluid such as liquid nitrogen
  • the cryogenic fluid will evaporate and displace the air from the volume confined by the shroud and the work piece.
  • the shroud will be filled with liquid and gaseous cryogen.
  • the shroud is preferably provided with an opening aligned with the orifice of the delivery nozzle(s).
  • aligned shall mean that the nozzle orifice and the opening in the front face of the shroud are arranged in such a way that the cryogenic fluid leaving the delivery nozzle passes part of the interior of the shroud, that is the essentially closed space, and then leaves the shroud through said opening in the front face of the shroud in order to be sprayed to or onto the work piece.
  • the shroud might surround only one delivery nozzle or more than one delivery nozzle, that is two or more delivery nozzles. Preferably all delivery nozzles for supplying the cryogenic fluid are located within one shroud.
  • the open front face of the shroud is closed by the work piece when the delivery nozzle for spraying the cryogenic fluid and the work piece are in working configuration.
  • working configuration shall mean that the delivery nozzle and the work piece are arranged in such a way that cryogenic fluid can be sprayed onto the work piece without causing condensation of atmospheric water vapour / moisture on the work piece or within the shroud. In particular, in the working configuration the shroud and the work piece form an essentially closed space.
  • the outer surface of the shroud is preferably kept at a temperature above the dew point temperature.
  • the dew point is defined as the temperature at which at a given pressure water vapour will condense into water.
  • the temperature of the outer walls of the shroud shall be above the dew point of the surrounding ambient air.
  • the outside of the shroud shall be kept at a temperature of at least a few degrees centigrade above the dew point temperature of the ambient air.
  • the outer surface of the shroud is kept at least at the temperature of the surrounding atmosphere. Thereby, condensation of water vapour at the outer surface of the shroud is avoided.
  • the shroud preferably comprises an enclosure, a shell or a box-like element with an opening arranged to be turned towards the workpiece.
  • the edge of the shroud which is directed towards the work piece is preferably designed to form a seal with the work piece.
  • a barrier which seals the opening in the front face of the shroud to avoid the intrusion of ambient air into the shroud.
  • the barrier prevents water vapour entering the shroud and water droplets from staining the work piece.
  • the barrier prevents condensation or icing from occurring inside the closed space, on the nozzles or on the workpiece because the ambient atmosphere is excluded and the inner space of the shroud only contains cold dry gas.
  • the barrier comprises one or more physical covers which can be arranged to cover the opening in the front face of the shroud.
  • the covers are movably connected to the shroud.
  • the covers can be rotated, slided and/or pivoted or swung relative to the shroud in order to close the opening in the front face.
  • covers are cover sheets, doors or door-like means, sliding doors, shields, lids, louvres or partition elements, such as partition walls.
  • the shroud has a cylindrical shape with a sectoral aperture or opening which is directed to the work piece.
  • One or more, especially two, covers are rotatably connected to the shroud and are able to move in an essentially circular motion.
  • the circular motion of the covers is preferably around the axis of the cylindrical shroud.
  • the covers can be moved into the shroud in order to uncover the opening in the front face of the shroud.
  • the covers can for example slide or rotate into the shroud.
  • the shroud could be provided with a guide rail, guide groove, guide bar or guide plate along which the cover is allowed to move.
  • the position and/or motion of the cover(s) is preferably linked to the relative position of the delivery nozzle and the shroud with respect to the work piece.
  • the cover or the covers are moved into the shroud and the opening in the shroud is uncovered by the cover(s) but sealed by the work piece.
  • the cover(s) cover more and more of the opening in the front face of the shroud.
  • the covers could be linked to the retraction mechanism by guide grooves or other means so that as the shroud and the delivery nozzle are retracted, the retractive motion will cause the cover(s) to close.
  • the cover(s) By such motion of the covers the opening in the front face of the shroud is always covered: In the working configuration the opening is covered by the work piece. When the shroud is far removed from the work piece the opening is closed by the cover and at a distance inbetween the opening is partly covered by the cover and partly by the work piece.
  • the cover can preferably be moved into the shroud in the working configuration. Therefore, it is preferred that the shroud comprises a space or pocket for the cover(s) where they fit in. It is further possible to continuously heat and/or purge the space or pocket with an inert gas or another dry gas.
  • the inert gas for example gaseous nitrogen, has preferably ambient temperature.
  • the covers are kept at a sufficient high temperature such that when they leave the shroud in order to close or seal the opening, the outside of the cover(s) is at a sufficient high temperature to prevent condensation or icing on their outer surfaces.
  • the temperature of the cover(s) is kept at or above the dew point of the surrounding ambient atmosphere.
  • an inert gas curtain prevents ambient air from entering the shroud in addition to the physical barrier or cover(s). Gas is blown parallel to the plane of the opening and/or in a direction from inside the shroud to the outside of the shroud forming a gas flow out of the shroud. Thereby, ambient air is pushed away from the opening and the ingress of humid air into the shroud is prevented.
  • the pressure of the gas blown into the vicinity of the gap between the shroud and the work piece is preferably controlled to be above the atmospheric pressure of the surrounding ambient air and above the pressure inside the essentially closed space. This ensures that air is not sucked into the essentially closed space and that no cold gaseous coolant leaves the essentially closed space through said gap.
  • the flow of gas forming the gas curtain preferably consists of dry gas.
  • the term 'dry gas' shall mean a gas which contains essentially no water vapour or such a low level of water vapour that no condensation or ice is formed when this gas comes into contact with the cryogenic fluid or with equipment such as the edge of the interior part of the shielding which has been cooled by the cryogenic fluid.
  • the dry gas will prevent formation of ice on the shielding means, especially on the edge of the opening.
  • the content of H 2 0 in the dry gas is less than 10 ppm or less than 10 vpm (parts per million by volume).
  • gaseous nitrogen is used as dry gas.
  • the gas outlet or gas outlets for supplying the dry gas to the opening of the shroud and to the gap between the shroud and the work piece are preferably in fluid communication with a source of gaseous nitrogen. It is possible to use other dry gases, in particular inert gases, as dry gas but gaseous nitrogen is preferred.
  • the invention is in particular used for cooling in a metal rolling process of rolling a metal strip.
  • the essentially closed space is defined by the shroud and the part of the outside surface of the work roll which shall be cooled.
  • the work roll is the work piece which is sprayed with the cryogenic fluid.
  • the opening of the shroud is closed by the work roll thereby forming an essentially closed space inside.
  • the essentially closed space does preferably not include the whole of the workpiece, in this case not the whole of the work roll.
  • the invention prevents condensation outside the essentially closed space and thus no water, ice or snow is formed which could fall onto the metal strip and damage it.
  • the opening in the front face of the shroud is covered by the barrier.
  • the barrier could be a physical barrier such as one or more doors or other covers.
  • the shroud might comprise a sealing member arranged to sealingly close the gap between the shroud and the work piece.
  • the cover(s) are also provided with a sealing member in order to seal the gap between the cover(s) and the work piece and/or between the covers themselves and/or between the cover(s) and the shroud.
  • the sealing member can comprise an elastic material, for example a plastic material.
  • the sealing member could also be realised by a pressure barrier or a gas flow which prevents any gas below the dew point from escaping from the essentially closed space into the area local to the work piece.
  • the outside of the shroud shall be kept at a temperature above the dew point of the surrounding ambient air, preferably above the temperature of the surrounding ambient air.
  • the means to keep the temperature of the outside of the shroud and/or of the cover(s) in the desired range may include passive elements, such as thermal insulation, which reduce the rate of heat transfer between the inside of the closed space and the outside walls of the shroud and/or of the cover(s).
  • passive elements such as thermal insulation, which reduce the rate of heat transfer between the inside of the closed space and the outside walls of the shroud and/or of the cover(s).
  • These means preferably comprise material with a low heat transfer coefficient, for example one or more layers of a solid material with a low thermal conductivity.
  • the means for keeping the outside of said shroud and/or of the cover(s) at a temperature above the dew point may also include active elements which keep the wall temperature above the dew point by heat supply, for example by provision of heating means, in particular electric heating means.
  • the shroud and/or the cover(s) are at least partly double-walled and a source of a gas is connected to the gap between said walls.
  • the shroud and/or the cover(s) comprise an inner and an outer wall and a gas is introduced into the gap between these walls in order to act as an insulator and to provide a source of heat to keep the outer wall above the dew point.
  • a gas is used which is at ambient temperature or even above ambient temperature or which has been warmed up to a temperature above ambient temperature.
  • the gap between the walls of the shroud and/or between the walls of the cover(s) comprises a gas outlet at or close to the gap between the shroud and/or the cover(s) and the work piece. At least part of the gas which is introduced into the gap between the walls of the shroud and/or of the cover(s) flows out of the gas outlet near the work piece.
  • the gas acts as a gas seal or pressure barrier and prevents atmospheric air from entering through this gap into the essentially closed space and cold gas from escaping from the closed space into the vicinity of the workpiece.
  • figure 1 schematically shows an apparatus for spraying liquid nitrogen onto a work roll
  • figure 2 shows an embodiment of the invention
  • figure 3 schematically shows a cross section of another embodiment in the working configuration which is very similar to the embodiment of figure 2, and figure 4 schematically shows a cross section of the embodiment of figure 3 in the maintenance configuration.
  • FIG. 1 schematically shows an apparatus for spraying liquid nitrogen onto a work roll 1 which is used for cold rolling a metal strip or metal foil, for example an aluminium foil.
  • Liquid nitrogen 2 is supplied via a supply line 3 to a plurality of delivery nozzles 4.
  • the liquid nitrogen leaves the delivery nozzles 4 in the form of nitrogen jets 5 directed to the surface of the roll 1.
  • the delivery nozzles 4 are surrounded by an enclosure 6 which serves as a shroud.
  • the enclosure or shroud 6 has in its front face an opening towards the work roll 1.
  • the shroud 6 is at least partly designed with double walls 7. Gaseous nitrogen 8 with room temperature is provided to the gap between the two walls 7 of the shroud 6.
  • the nitrogen gas 8 flows between the two walls 7 and thereby thermally insulates the shroud 6.
  • the outer surface of the shroud 6 remains warm although liquid nitrogen is evaporated inside the essentially closed space confined by the shroud 6 and the work roll 1.
  • the warm gas does not only insulate the outer wall but also provides heat.
  • the dry gaseous nitrogen leaves the annular gap 7 between the double walls close to the edge of the opening of the shroud 6, i.e. in operation close to the work roll 1.
  • the shroud walls or a part of the shroud walls comprise an outer layer of stainless steel coated on its inner surface and a second layer of a porous insulation material, such as an aerogel, which is bonded to an innermost layer made of polystyrene or another thermoplastic polymer.
  • the warm nitrogen gas 9 leaving the gap 7 acts as a gas barrier and blocks the small gap between the shroud 6 and the roll 1 and thus prevents air from entering into the interior of the shroud 6 and cold gas from escaping.
  • the pressure of the gas flow 9 is above the atmospheric pressure and above the pressure inside the essentially closed space confined by the shroud 6.
  • the shroud 6 further comprises a duct 1 1 which allows to withdraw gas from the essentially closed space confined by the shroud 6.
  • the gas flow through duct 1 1 is controlled in such a way that surplus nitrogen gas is extracted from the shroud 6 and from the surface of the roll 1. That gas would otherwise create a turbulence which may affect the efficiency of the liquid nitrogen spraying.
  • the gas flow through duct 1 1 should not suck in air from the surroundings into the enclosure 6 via the gap between the enclosure 6 and the roll 1 . That means the gas flow through duct 1 1 is preferably controlled to achieve an optimum of the above described effects.
  • the gas flow through duct 11 is preferably controlled depending on the design of the enclosure 6, the pressure and flow of the liquid nitrogen 2, 5 and/or the pressure and flow of the dry gas 8 passed through the double-walls 7.
  • the back of the enclosure 6 - behind or upstream the nozzles 4 - and the supply line 3 are insulated to ensure that those parts as well as the double walled part 7 are above the dew point. It is further preferred to also insulate the exhaust duct 11 , at least within the critical region where any condensation on the exhaust duct 1 1 could get onto the strip 10.
  • Figure 1 shows the apparatus in the operation configuration, that means roll 1 , nozzles 4 and shroud 6 are arranged in such a way that nitrogen can be sprayed onto the roll surface without getting any water or condensation onto the roll 1 and into the shroud 6.
  • the shroud 6 forms together with the roll 1 an essentially closed space. From time to time it is necessary to change the roll 1 or to carry out some maintenance operations at the roll 1.
  • the shroud 6 still contains cold and moisture in the atmospheric air entering the shroud 6 or contacting the delivering nozzles 4 would condense.
  • Figures 2 shows an embodiment of the invention to avoid condensation of atmospheric air inside the shroud 6 when the shroud 6 and the roll 1 are moved apart from each other.
  • Figures 3 and 4 show a cross section of another inventive embodiment which is very similar to the embodiment of figure 2. In the following figures 2 to 4 will be explained together and same reference numbers will be used for the same features.
  • the shroud 6 has the shape of a cylinder with a recess 20 for the roll 1 in its front face. In the working configuration, as shown in figure 2, the roll 1 fits into the recess 20.
  • the shroud 6 comprises a fixed outer part 21 of cylindrical shape with the recess 20 for the roll 1 and two movable inner shields 22a, 22b of sectoral shape.
  • the two inner shields 22a, 22b are rotatable with respect to the symmetry axis 23 of the cylindrical shroud 6.
  • the shields 22a, 22b can either be moved or rotated to a closed position wherein the shields 22a, 22b cover the recess 20 and close the shroud 6 (figures 2 and 4).
  • the shields 22a, 22b can be moved to an open position wherein the shields 22a, 22b are moved into the shroud 6 such that the recess 20 is open (figure 3).
  • the side walls 43 of the fixed outer part 21 are profiled to match the curvature of the work roll 1 so that they seal against the work roll 1 , i.e. the fixed part 21 is sealed against the work roll 1 all the way around the opening, at the top, at the bottom and at the sides. It is also possible to profile the side walls of the shields 22a, 22b such that they match the curvature of the work roll 1 in the. working configuration. In that case it is preferred to make the side walls of the shields 22a, 22b overlap in the maintenance
  • both shields 22a, 22b are provided with contact rolls 38.
  • the contact rolls 38 are in contact with the work roll 1 and ensure that the same gap is maintained between the shields 22a, 22b and the work roll 1.
  • the movable shields 22a, 22b allow the shroud 6 to fit many different sizes of work rolls 1 by varying the degree of opening the recess 20 in the shroud 6. As long as the contact rolls 38 are in contact with the roll 1 there is always the same gap between the shroud 6 or the shields 2 , 22 and the roll 1.
  • both sectoral shields 22a, 22b are moved backwards into the shroud 6 so that the recess 20 can be covered by the roll 1.
  • the adjusting mechanism guarantees that the inner space of the shroud 6 is always sealed to the surrounding atmosphere:
  • the opening in the shroud 6 is covered by the work roll 1.
  • the opening in the shroud 6 is closed by the sectoral shaped shields 22a, 22b.
  • the shields 22a, 22b are closed depending on the distance between shroud 6 and roll 1.
  • the adjusting mechanism can be realised by rolls, sensors and controllers in combination with means to move the shields 22a, 22b.
  • Such means to move the shields 22a, 22b can, for example, be a motor, hydraulics, an elastic element or a spring element.
  • the fixed outer part 21 is double-walled forming an outer pocket 26.
  • the outer pocket 26 is purged with a gas, preferably a warm gas and/or an inert gas, which is supplied via feed port 28.
  • the outer pocket 26 insulates the shroud 6 and keeps the outer surface of the shroud 6 warm such that no condensation of humid air will occur.
  • the purge gas 31 flows through the outer pocket 26 and exits the outer pocket 26 at the edge 27.
  • the purge gas 31 seals the joint between the outer part 21 and the work roll 1.
  • a portion 30 of the purge gas will leave the outer pocket to the ambient atmosphere outside the shroud 6
  • another portion 29 of the purge gas will leave the outer pocket 26 and enter the interior of the shroud 6.
  • the purge gas flowing through the outer pocket 26 has a double function: First, it insulates the shroud 6 and keeps the outer wall of the outer part 21 warm to avoid condensation on the outer part 21. Second, in the working configuration the purge gas leaving the outer pocket 26 at the edge 27 works as a gas seal between the shroud 6 and the work roll 1.
  • the rotatable inner shields 22a, 22b are also double-walled. Between the double walls a passage 32 is formed. As shown in figures 3 and 4 the passage 32 is preferably closed by a bar 33 at its inner end which is moved into the outer part 21. The outer wall of the passage 22 comprises an opening 34 close to the bar 33. The fixed outer part 21 has an aperture 35 with a gas port 36.
  • a purge gas 37 is supplied to gas port 36 and flows through aperture 35 and opening 34 into the passage 32.
  • the purge gas 37 continues to flow through the passage 32 and leaves it at the end where the two shields 22a, 22b abut.
  • the purge gas 37 keeps the outer surface of the shields 22a, 22b warm and works as a gas seal between the two shields 22a, 22b.
  • the double wall structure of the shields 22a, 22b can also be used to gas seal the gap between the shroud 6 and the work roll 1.
  • Purge gas 37 supplied via gas port 36 flows through aperture 35 into the gap between the outer part 21 and the shield 22a, 22b and then through opening 34 into passage 32.
  • the purge gas 37 leaves the passage 32 close to the contact area between the outer part 21 and the work roll 1 and forms an additional gas seal.
  • the shields 22a, 22b are also double-walled forming a passage for a purge gas between the walls of the double-wall structure.
  • the gas port 39 for the purge gas is directly connected to the shields 22a, 22b.
  • the shroud is essentially formed as a right circular cylinder.
  • the shroud might also comprise additional feed ports 40, 41 , 42 for feeding purge gas to the side walls 43 of the fixed outer part 21 and to the gaps between the side walls 44 of the shields and the side walls 43 fixed outer part 21.
  • the term "side wall of the fixed outer part” shall mean the base area(s) of the right circular cylinder forming the shroud 6.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
  • Pressure Vessels And Lids Thereof (AREA)
  • Auxiliary Devices For Machine Tools (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Vacuum Packaging (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)

Abstract

Method and apparatus to isolate the cold in cryogenic equipment The invention relates to an apparatus and a method for spraying a cryogenic fluid to a workpiece (1) comprising a cryogen feed line, at least one delivery nozzle for delivering the cryogenic fluid, a shroud (6) which surrounds at least part of said delivery nozzle and which has a front face with an opening which is directed to the workpiece (1). The shroud (6) and the workpiece (1) are movable relative to each other between a working configuration and a maintenance configuration. In the maintenance configuration the shroud (6) comprises a barrier (22a, 22b) which prevents or minimizes ambient air from entering the shroud (6).

Description

Description
Method and apparatus to isolate the cold in cryogenic equipment
The invention relates to an apparatus for spraying a cryogenic fluid to a work piece comprising a cryogen feed line, at least one delivery nozzle for delivering the cryogenic fluid, a shroud which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece, said shroud and said work piece being movable relative to each other between a working configuration and a maintenance configuration, wherein in said maintenance configuration the front face of the shroud is not completely closed or covered by the work piece, said shroud being arranged to form an essentially closed space together with the work piece in said working configuration.
The invention further relates to a method for spraying a cryogenic fluid to a work piece wherein said cryogenic fluid is sprayed by means of at least one delivery nozzle, and wherein a shroud is provided which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece, and wherein said shroud and said workpiece can be arranged in a working configuration wherein said shroud forms an essentially closed space together with said work piece, and wherein said shroud and said workpiece can be arranged in a maintenance configuration wherein said opening of said shroud is not sealed by the work piece.
It is well known that metal rolling processes produce a lot of heat and that the most common method for removing this heat is to spray a coolant onto the rolls. The most common coolants are water and kerosene but recently the use of cryogenic fluids has been suggested in WO 2012/1 10241 A1.
A major problem with the use of cryogenic fluids for cooling in some metal rolling processes such as the cold rolling of aluminium is that moisture from the surrounding atmosphere can condense onto the equipment and form water, ice or snow which can then fall or be carried onto the strip and damage it.
WO 2012/1 10241 A1 proposes to provide a shroud which surrounds at least part of the delivery nozzle for spraying the cryogenic fluid. The shroud is arranged to form an essentially closed space together with the work piece and it comprises means for keeping the outside of said shielding means at a temperature above the dew point.
When the spraying system according to WO 2012/110241 A1 is in operation, i.e. when cryogenic fluid is sprayed onto the work piece, the shroud and the work piece are arranged close to each other and an essentially closed space is formed which prevents atmospheric air from entering the area within the shroud.
From time to time it is necessary to stop the spraying process and to retract the delivery nozzle and the shroud from the work piece for maintenance operations. When the delivery nozzle with the shroud is retracted from the work piece, the interior of the shroud is no longer closed to the surrounding atmosphere and ambient air will enter the shroud. Since the interior of the shroud is still very cold, there is a certain risk that moisture from the ambient air will condense on the shroud.
An object of this invention is to avoid getting any water into the shroud when it has been retracted from the work piece.
Another object of the invention is to avoid getting moisture into the shroud while the shroud is being retracted from the work piece.
Another object of the invention is to prevent water droplets from staining the work piece. At least some of these objects are achieved by an apparatus for spraying a cryogenic fluid to a work piece comprising
- a cryogen feed line,
- at least one delivery nozzle for delivering the cryogenic fluid,
- a shroud which surrounds at least part of said delivery nozzle and which has a front face with an opening which is directed to the workpiece,
- said shroud and said work piece being movable relative to each other between a working configuration and a maintenance configuration,
- wherein in said maintenance configuration the front face of the shroud is not completely closed or covered by the work piece
- said shroud being arranged to form an essentially closed space together with the work piece in said working configuration,
and which is characterized in that
in said maintenance configuration said shroud comprises a barrier which prevents or minimizes ambient air from entering the shroud shroud and wherein said barrier comprises one or more physical covers which can be arranged to cover said opening.
The inventive method for spraying a cryogenic fluid to a work piece wherein said cryogenic fluid is sprayed by means of at least one delivery nozzle, and wherein a shroud is provided which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece, wherein said shroud and said workpiece can be arranged in a working configuration wherein said shroud forms an essentially closed space together with said work piece, and wherein said shroud and said workpiece can be arranged in a maintenance configuration wherein said opening of said shroud is not sealed by the work piece, is characterized in that in said
maintenance configuration said opening is sealed by means of a barrier which prevents or minimizes ambient air from entering the shroud, wherein said barrier comprises one or more covers which are arranged to cover said opening in said maintenance configuration. When a cryogenic fluid, such as liquid nitrogen, is sprayed, the cryogenic fluid will evaporate and displace the air from the volume confined by the shroud and the work piece. The shroud will be filled with liquid and gaseous cryogen.
The shroud is preferably provided with an opening aligned with the orifice of the delivery nozzle(s). The term "aligned" shall mean that the nozzle orifice and the opening in the front face of the shroud are arranged in such a way that the cryogenic fluid leaving the delivery nozzle passes part of the interior of the shroud, that is the essentially closed space, and then leaves the shroud through said opening in the front face of the shroud in order to be sprayed to or onto the work piece.
The shroud might surround only one delivery nozzle or more than one delivery nozzle, that is two or more delivery nozzles. Preferably all delivery nozzles for supplying the cryogenic fluid are located within one shroud. According to the invention the open front face of the shroud is closed by the work piece when the delivery nozzle for spraying the cryogenic fluid and the work piece are in working configuration. The term "working configuration" shall mean that the delivery nozzle and the work piece are arranged in such a way that cryogenic fluid can be sprayed onto the work piece without causing condensation of atmospheric water vapour / moisture on the work piece or within the shroud. In particular, in the working configuration the shroud and the work piece form an essentially closed space.
The outer surface of the shroud is preferably kept at a temperature above the dew point temperature. The dew point is defined as the temperature at which at a given pressure water vapour will condense into water. According to the invention, the temperature of the outer walls of the shroud shall be above the dew point of the surrounding ambient air. In particular, the outside of the shroud shall be kept at a temperature of at least a few degrees centigrade above the dew point temperature of the ambient air. In a preferred embodiment the outer surface of the shroud is kept at least at the temperature of the surrounding atmosphere. Thereby, condensation of water vapour at the outer surface of the shroud is avoided.
The shroud preferably comprises an enclosure, a shell or a box-like element with an opening arranged to be turned towards the workpiece. The edge of the shroud which is directed towards the work piece is preferably designed to form a seal with the work piece.
For maintenance or for other operations it is possible to retract the delivery nozzle with the shroud and the work piece from each other. That configuration when the delivery nozzle with the shroud and the work piece are not positioned close to each other, do not abut each other and when the opening in the front face of the shroud is not completely closed or covered by the work piece shall be called the "maintenance configuration".
According to the invention in the maintenance configuration a barrier is provided which seals the opening in the front face of the shroud to avoid the intrusion of ambient air into the shroud. Thus the barrier prevents water vapour entering the shroud and water droplets from staining the work piece. The barrier prevents condensation or icing from occurring inside the closed space, on the nozzles or on the workpiece because the ambient atmosphere is excluded and the inner space of the shroud only contains cold dry gas.
According to the invention the barrier comprises one or more physical covers which can be arranged to cover the opening in the front face of the shroud. Preferably, the covers are movably connected to the shroud. For example, the covers can be rotated, slided and/or pivoted or swung relative to the shroud in order to close the opening in the front face. Examples of such covers are cover sheets, doors or door-like means, sliding doors, shields, lids, louvres or partition elements, such as partition walls.
According to one embodiment the shroud has a cylindrical shape with a sectoral aperture or opening which is directed to the work piece. One or more, especially two, covers are rotatably connected to the shroud and are able to move in an essentially circular motion. The circular motion of the covers is preferably around the axis of the cylindrical shroud.
According to another embodiment the covers can be moved into the shroud in order to uncover the opening in the front face of the shroud. The covers can for example slide or rotate into the shroud. The shroud could be provided with a guide rail, guide groove, guide bar or guide plate along which the cover is allowed to move.
The position and/or motion of the cover(s) is preferably linked to the relative position of the delivery nozzle and the shroud with respect to the work piece. When the shroud is positioned close to the work piece as in the working configuration, the cover or the covers are moved into the shroud and the opening in the shroud is uncovered by the cover(s) but sealed by the work piece. With increasing distance of the shroud from the work piece the cover(s) cover more and more of the opening in the front face of the shroud. The covers could be linked to the retraction mechanism by guide grooves or other means so that as the shroud and the delivery nozzle are retracted, the retractive motion will cause the cover(s) to close. It is also possible to move the cover(s) by other means such as a motor or hydraulics. By such motion of the covers the opening in the front face of the shroud is always covered: In the working configuration the opening is covered by the work piece. When the shroud is far removed from the work piece the opening is closed by the cover and at a distance inbetween the opening is partly covered by the cover and partly by the work piece.
As described above the cover can preferably be moved into the shroud in the working configuration. Therefore, it is preferred that the shroud comprises a space or pocket for the cover(s) where they fit in. It is further possible to continuously heat and/or purge the space or pocket with an inert gas or another dry gas. The inert gas, for example gaseous nitrogen, has preferably ambient temperature. By heating and/or purging the covers are kept at a sufficient high temperature such that when they leave the shroud in order to close or seal the opening, the outside of the cover(s) is at a sufficient high temperature to prevent condensation or icing on their outer surfaces. Preferably the temperature of the cover(s) is kept at or above the dew point of the surrounding ambient atmosphere.
According to another embodiment an inert gas curtain prevents ambient air from entering the shroud in addition to the physical barrier or cover(s). Gas is blown parallel to the plane of the opening and/or in a direction from inside the shroud to the outside of the shroud forming a gas flow out of the shroud. Thereby, ambient air is pushed away from the opening and the ingress of humid air into the shroud is prevented.
The pressure of the gas blown into the vicinity of the gap between the shroud and the work piece is preferably controlled to be above the atmospheric pressure of the surrounding ambient air and above the pressure inside the essentially closed space. This ensures that air is not sucked into the essentially closed space and that no cold gaseous coolant leaves the essentially closed space through said gap.
The flow of gas forming the gas curtain preferably consists of dry gas. The term 'dry gas' shall mean a gas which contains essentially no water vapour or such a low level of water vapour that no condensation or ice is formed when this gas comes into contact with the cryogenic fluid or with equipment such as the edge of the interior part of the shielding which has been cooled by the cryogenic fluid. The dry gas will prevent formation of ice on the shielding means, especially on the edge of the opening.
Preferably, the content of H20 in the dry gas is less than 10 ppm or less than 10 vpm (parts per million by volume). According to another preferred embodiment gaseous nitrogen is used as dry gas. The gas outlet or gas outlets for supplying the dry gas to the opening of the shroud and to the gap between the shroud and the work piece are preferably in fluid communication with a source of gaseous nitrogen. It is possible to use other dry gases, in particular inert gases, as dry gas but gaseous nitrogen is preferred.
The invention is in particular used for cooling in a metal rolling process of rolling a metal strip. In that case the essentially closed space is defined by the shroud and the part of the outside surface of the work roll which shall be cooled. The work roll is the work piece which is sprayed with the cryogenic fluid. In the working configuration the opening of the shroud is closed by the work roll thereby forming an essentially closed space inside. The essentially closed space does preferably not include the whole of the workpiece, in this case not the whole of the work roll. The invention prevents condensation outside the essentially closed space and thus no water, ice or snow is formed which could fall onto the metal strip and damage it.
In the maintenance configuration, for example when a roll shall be changed, the opening in the front face of the shroud is covered by the barrier. The barrier could be a physical barrier such as one or more doors or other covers.
The shroud might comprise a sealing member arranged to sealingly close the gap between the shroud and the work piece. Preferably, the cover(s) are also provided with a sealing member in order to seal the gap between the cover(s) and the work piece and/or between the covers themselves and/or between the cover(s) and the shroud. The sealing member can comprise an elastic material, for example a plastic material. The sealing member could also be realised by a pressure barrier or a gas flow which prevents any gas below the dew point from escaping from the essentially closed space into the area local to the work piece.
According to the invention the outside of the shroud shall be kept at a temperature above the dew point of the surrounding ambient air, preferably above the temperature of the surrounding ambient air. In the maintenance configuration the same applies to the cover(s). The means to keep the temperature of the outside of the shroud and/or of the cover(s) in the desired range may include passive elements, such as thermal insulation, which reduce the rate of heat transfer between the inside of the closed space and the outside walls of the shroud and/or of the cover(s). These means preferably comprise material with a low heat transfer coefficient, for example one or more layers of a solid material with a low thermal conductivity. Further, the means for keeping the outside of said shroud and/or of the cover(s) at a temperature above the dew point may also include active elements which keep the wall temperature above the dew point by heat supply, for example by provision of heating means, in particular electric heating means. According to another preferred embodiment the shroud and/or the cover(s) are at least partly double-walled and a source of a gas is connected to the gap between said walls. The shroud and/or the cover(s) comprise an inner and an outer wall and a gas is introduced into the gap between these walls in order to act as an insulator and to provide a source of heat to keep the outer wall above the dew point. Preferably a gas is used which is at ambient temperature or even above ambient temperature or which has been warmed up to a temperature above ambient temperature.
It is further preferred that the gap between the walls of the shroud and/or between the walls of the cover(s) comprises a gas outlet at or close to the gap between the shroud and/or the cover(s) and the work piece. At least part of the gas which is introduced into the gap between the walls of the shroud and/or of the cover(s) flows out of the gas outlet near the work piece. The gas acts as a gas seal or pressure barrier and prevents atmospheric air from entering through this gap into the essentially closed space and cold gas from escaping from the closed space into the vicinity of the workpiece.
Therefore, any condensation is kept away from the essentially closed space and the cold inner parts of the system.
Instead of or in addition to the gas outlet(s) mentioned above it is also possible to have a separate gas feed line for feeding a gas, preferably a warm gas, close to the gap between the shroud and/or the cover(s) and the work piece which then acts as a shroud or gas barrier to prevent cold gas getting out and ambient air getting into the essentially closed space. The present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: figure 1 schematically shows an apparatus for spraying liquid nitrogen onto a work roll,
figure 2 shows an embodiment of the invention,
figure 3 schematically shows a cross section of another embodiment in the working configuration which is very similar to the embodiment of figure 2, and figure 4 schematically shows a cross section of the embodiment of figure 3 in the maintenance configuration.
Figure 1 schematically shows an apparatus for spraying liquid nitrogen onto a work roll 1 which is used for cold rolling a metal strip or metal foil, for example an aluminium foil. Liquid nitrogen 2 is supplied via a supply line 3 to a plurality of delivery nozzles 4. The liquid nitrogen leaves the delivery nozzles 4 in the form of nitrogen jets 5 directed to the surface of the roll 1. During and after the spraying process the liquid nitrogen evaporates and forms gaseous nitrogen. The delivery nozzles 4 are surrounded by an enclosure 6 which serves as a shroud. The enclosure or shroud 6 has in its front face an opening towards the work roll 1. The shroud 6 is at least partly designed with double walls 7. Gaseous nitrogen 8 with room temperature is provided to the gap between the two walls 7 of the shroud 6. The nitrogen gas 8 flows between the two walls 7 and thereby thermally insulates the shroud 6. The outer surface of the shroud 6 remains warm although liquid nitrogen is evaporated inside the essentially closed space confined by the shroud 6 and the work roll 1. The warm gas does not only insulate the outer wall but also provides heat. The dry gaseous nitrogen leaves the annular gap 7 between the double walls close to the edge of the opening of the shroud 6, i.e. in operation close to the work roll 1.
In addition to or alternatively to the double wall insulation described above, it is possible to use a cartridge heater in the shroud 6 to heat up the outer walls or part of the outer walls of the shroud 6. It is further possible to provide the walls of the shroud 6 with insulation material and/or to contruct the shroud walls of different layers. As an example, the shroud walls or a part of the shroud walls comprise an outer layer of stainless steel coated on its inner surface and a second layer of a porous insulation material, such as an aerogel, which is bonded to an innermost layer made of polystyrene or another thermoplastic polymer. The warm nitrogen gas 9 leaving the gap 7 acts as a gas barrier and blocks the small gap between the shroud 6 and the roll 1 and thus prevents air from entering into the interior of the shroud 6 and cold gas from escaping. The pressure of the gas flow 9 is above the atmospheric pressure and above the pressure inside the essentially closed space confined by the shroud 6.
The shroud 6 further comprises a duct 1 1 which allows to withdraw gas from the essentially closed space confined by the shroud 6. The gas flow through duct 1 1 is controlled in such a way that surplus nitrogen gas is extracted from the shroud 6 and from the surface of the roll 1. That gas would otherwise create a turbulence which may affect the efficiency of the liquid nitrogen spraying. Furthermore, potentially
asphyxiating inert nitrogen gas is removed from the work environment. On the other hand, the gas flow through duct 1 1 should not suck in air from the surroundings into the enclosure 6 via the gap between the enclosure 6 and the roll 1 . That means the gas flow through duct 1 1 is preferably controlled to achieve an optimum of the above described effects. The gas flow through duct 11 is preferably controlled depending on the design of the enclosure 6, the pressure and flow of the liquid nitrogen 2, 5 and/or the pressure and flow of the dry gas 8 passed through the double-walls 7.
Preferably, the back of the enclosure 6 - behind or upstream the nozzles 4 - and the supply line 3 are insulated to ensure that those parts as well as the double walled part 7 are above the dew point. It is further preferred to also insulate the exhaust duct 11 , at least within the critical region where any condensation on the exhaust duct 1 1 could get onto the strip 10. Figure 1 shows the apparatus in the operation configuration, that means roll 1 , nozzles 4 and shroud 6 are arranged in such a way that nitrogen can be sprayed onto the roll surface without getting any water or condensation onto the roll 1 and into the shroud 6. The shroud 6 forms together with the roll 1 an essentially closed space. From time to time it is necessary to change the roll 1 or to carry out some maintenance operations at the roll 1. In that case the liquid nitrogen supply to the delivery nozzles 4 is stopped and the roll 1 is retracted from the nozzles 4 with the shroud 6 or the nozzles 4 with shroud 6 are retracted from the roll 1. This configuration when roll 1 on one hand and nozzles 4 and shroud 6 on the other hand are retracted from each other shall be called the maintenance configuration. In the maintenance configuration the shroud 6 is no more in direct contact with the rolh or in general with the work piece.
At least in the first phase after the shroud 6 and the roll 1 have been retracted from each other, the shroud 6 still contains cold and moisture in the atmospheric air entering the shroud 6 or contacting the delivering nozzles 4 would condense.
Figures 2 shows an embodiment of the invention to avoid condensation of atmospheric air inside the shroud 6 when the shroud 6 and the roll 1 are moved apart from each other. Figures 3 and 4 show a cross section of another inventive embodiment which is very similar to the embodiment of figure 2. In the following figures 2 to 4 will be explained together and same reference numbers will be used for the same features.
The shroud 6 has the shape of a cylinder with a recess 20 for the roll 1 in its front face. In the working configuration, as shown in figure 2, the roll 1 fits into the recess 20.
Thereby, the work roll 1 covers and seals the opening of the shroud 6 so that the inner space of the shroud 6 is closed to the surrounding atmosphere. Ambient air and in particular moisture cannot enter the shroud 6. The shroud 6 comprises a fixed outer part 21 of cylindrical shape with the recess 20 for the roll 1 and two movable inner shields 22a, 22b of sectoral shape. The two inner shields 22a, 22b are rotatable with respect to the symmetry axis 23 of the cylindrical shroud 6. The shields 22a, 22b can either be moved or rotated to a closed position wherein the shields 22a, 22b cover the recess 20 and close the shroud 6 (figures 2 and 4). Or the shields 22a, 22b can be moved to an open position wherein the shields 22a, 22b are moved into the shroud 6 such that the recess 20 is open (figure 3). The side walls 43 of the fixed outer part 21 are profiled to match the curvature of the work roll 1 so that they seal against the work roll 1 , i.e. the fixed part 21 is sealed against the work roll 1 all the way around the opening, at the top, at the bottom and at the sides. It is also possible to profile the side walls of the shields 22a, 22b such that they match the curvature of the work roll 1 in the. working configuration. In that case it is preferred to make the side walls of the shields 22a, 22b overlap in the maintenance
configuration.
According to the embodiment of figure 2 both shields 22a, 22b are provided with contact rolls 38. In the working configuration the contact rolls 38 are in contact with the work roll 1 and ensure that the same gap is maintained between the shields 22a, 22b and the work roll 1. The movable shields 22a, 22b allow the shroud 6 to fit many different sizes of work rolls 1 by varying the degree of opening the recess 20 in the shroud 6. As long as the contact rolls 38 are in contact with the roll 1 there is always the same gap between the shroud 6 or the shields 2 , 22 and the roll 1.
In the working configuration the contact rolls 38 are in contact with the work roll 1. Both sectoral shields 22a, 22b are moved backwards into the shroud 6 so that the recess 20 can be covered by the roll 1. There could also be an adjusting mechanism which controls the position of the sectoral shields 22a, 22b. That means, when moving the shroud 6 a short distance away from the work roll 1 the shields 22a, 22b will be closed to such an extent that the contact rolls 38 remain in contact with the work roll 1. With increasing distance between shroud 6 and work roll 1 the shields 22a, 22b will close more and more until they completely cover the opening or recess 20 of the shroud 6.
The adjusting mechanism guarantees that the inner space of the shroud 6 is always sealed to the surrounding atmosphere:
In the working configuration the opening in the shroud 6 is covered by the work roll 1. In the maintenance configuration when shroud 6 and roll 1 are spaced apart from each other the opening in the shroud 6 is closed by the sectoral shaped shields 22a, 22b. And during the retraction process when the shroud 6 is moving away from the work roll 1 the shields 22a, 22b are closed depending on the distance between shroud 6 and roll 1.
The adjusting mechanism can be realised by rolls, sensors and controllers in combination with means to move the shields 22a, 22b. Such means to move the shields 22a, 22b can, for example, be a motor, hydraulics, an elastic element or a spring element. In figures 2 to 4 the fixed outer part 21 is double-walled forming an outer pocket 26. The outer pocket 26 is purged with a gas, preferably a warm gas and/or an inert gas, which is supplied via feed port 28. The outer pocket 26 insulates the shroud 6 and keeps the outer surface of the shroud 6 warm such that no condensation of humid air will occur. The purge gas 31 flows through the outer pocket 26 and exits the outer pocket 26 at the edge 27. In the working configuration the purge gas 31 seals the joint between the outer part 21 and the work roll 1. A portion 30 of the purge gas will leave the outer pocket to the ambient atmosphere outside the shroud 6, another portion 29 of the purge gas will leave the outer pocket 26 and enter the interior of the shroud 6.
The purge gas flowing through the outer pocket 26 has a double function: First, it insulates the shroud 6 and keeps the outer wall of the outer part 21 warm to avoid condensation on the outer part 21. Second, in the working configuration the purge gas leaving the outer pocket 26 at the edge 27 works as a gas seal between the shroud 6 and the work roll 1.
The rotatable inner shields 22a, 22b are also double-walled. Between the double walls a passage 32 is formed. As shown in figures 3 and 4 the passage 32 is preferably closed by a bar 33 at its inner end which is moved into the outer part 21. The outer wall of the passage 22 comprises an opening 34 close to the bar 33. The fixed outer part 21 has an aperture 35 with a gas port 36.
In the maintenance configuration as shown in figure 4 a purge gas 37 is supplied to gas port 36 and flows through aperture 35 and opening 34 into the passage 32. The purge gas 37 continues to flow through the passage 32 and leaves it at the end where the two shields 22a, 22b abut. The purge gas 37 keeps the outer surface of the shields 22a, 22b warm and works as a gas seal between the two shields 22a, 22b. In the working configuration (figure 3) the double wall structure of the shields 22a, 22b can also be used to gas seal the gap between the shroud 6 and the work roll 1. Purge gas 37 supplied via gas port 36 flows through aperture 35 into the gap between the outer part 21 and the shield 22a, 22b and then through opening 34 into passage 32. The purge gas 37 leaves the passage 32 close to the contact area between the outer part 21 and the work roll 1 and forms an additional gas seal. In the embodiment according to figure 2 the shields 22a, 22b are also double-walled forming a passage for a purge gas between the walls of the double-wall structure. In this case the gas port 39 for the purge gas is directly connected to the shields 22a, 22b.
In the embodiments according to figures 2 to 4 the shroud is essentially formed as a right circular cylinder. In that case the shroud might also comprise additional feed ports 40, 41 , 42 for feeding purge gas to the side walls 43 of the fixed outer part 21 and to the gaps between the side walls 44 of the shields and the side walls 43 fixed outer part 21. The term "side wall of the fixed outer part" shall mean the base area(s) of the right circular cylinder forming the shroud 6.

Claims

Claims
1. Apparatus for spraying a cryogenic fluid (2) to a work piece (1) comprising
- a cryogen feed line (3),
- at least one delivery nozzle (4) for delivering the cryogenic fluid (2),
- a shroud (6) which surrounds at least part of said delivery nozzle (4) and which has a front face with an opening which is directed to the work piece,
- said shroud and said work piece being movable relative to each other between a working configuration and a maintenance configuration,
- wherein in said maintenance configuration the front face of the shroud is not completely closed or covered by the work piece,
- said shroud (6) being arranged to form an essentially closed space together with the work piece (1) in said working configuration,
characterized in that
in said maintenance configuration said shroud comprises a barrier which prevents or minimizes ambient air from entering the shroud and wherein said barrier comprises one or more physical covers which can be arranged to cover said opening.
2. Apparatus according to claim 1 characterized in that said covers are rotatably or slidably engaged with said shroud.
3. Apparatus according to any of the preceding claims characterized in that the
position of the cover(s) relative to the shroud is controlled with respect to the position of the shroud relative to the work piece.
4. Apparatus according to any of the preceding claims characterized in that said cover(s) can be moved into the shroud.
5. Apparatus according to any of the preceding claims characterized in that said shroud comprises a gas blowing means positioned close to the opening of the shroud for blowing an inert gas in a direction parallel to said opening and/or in a direction from the inside of the shroud to the outside of the shroud so as to suppress intrusion of ambient air into the shroud.
Apparatus according to any of the preceding claims characterized in that said shroud comprises an adjusting mechanism which maintains the gap between the cover(s) and the work piece during retraction of the shroud from the work piece.
Method for spraying a cryogenic fluid to a work piece
- wherein said cryogenic fluid is sprayed by means of at least one delivery nozzle,
- and wherein a shroud is provided which surrounds at least part of said delivery nozzle and which has an opening which is directed to the workpiece,
- and wherein said shroud and said workpiece can be arranged in a working configuration wherein said shroud forms an essentially closed space together with said work piece,
- and wherein said shroud and said workpiece can be arranged in a maintenance configuration wherein said opening of said shroud is not sealed by the work piece, characterized in that
in said maintenance configuration said opening is sealed by means of a barrier which prevents or minimizes ambient air from entering the shroud wherein said barrier comprises one or more covers which are arranged to cover said opening in said maintenance configuration.
8. Method according to claim 7 characterized in that the position of the cover(s)
relative to the shroud is controlled with respect to the position of the shroud relative to the work piece.
9. Method according to any of claims 7 or 8 characterized in that said cover(s) are at least partly moved into the shroud in said maintenance configuration.
10. Method according to any of claims 7 to 9 characterized in that the cover(s) or portions of the cover(s) are purged with an inert gas.
1 1. Method according to any of the claims 7 to 10 characterized in that an inert gas is blown in a direction parallel to said opening and/or in a direction from the inside of the shroud to the outside of the shroud so as to suppress intrusion of ambient air into the shroud.
PCT/EP2014/003185 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment WO2015086119A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
EP14803052.1A EP3079841B1 (en) 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment
BR112016013035A BR112016013035A2 (en) 2013-12-09 2014-11-27 METHOD AND DEVICE FOR INSULATING COLD IN CRYOGENIC EQUIPMENT
JP2016538089A JP6516745B2 (en) 2013-12-09 2014-11-27 Method and apparatus for thermally insulating low temperature in low temperature equipment
CN201480067528.9A CN106163683B (en) 2013-12-09 2014-11-27 Isolate the method and apparatus of cold in Cryo Equipment
ES14803052.1T ES2687785T3 (en) 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment
KR1020167018294A KR20160096165A (en) 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment
US15/101,484 US20160303626A1 (en) 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP13005710.2 2013-12-09
EP13005710.2A EP2881186A1 (en) 2013-12-09 2013-12-09 Method and apparatus to isolate the cold in cryogenic equipment

Publications (1)

Publication Number Publication Date
WO2015086119A1 true WO2015086119A1 (en) 2015-06-18

Family

ID=49884857

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2014/003185 WO2015086119A1 (en) 2013-12-09 2014-11-27 Method and apparatus to isolate the cold in cryogenic equipment

Country Status (8)

Country Link
US (1) US20160303626A1 (en)
EP (2) EP2881186A1 (en)
JP (1) JP6516745B2 (en)
KR (1) KR20160096165A (en)
CN (1) CN106163683B (en)
BR (1) BR112016013035A2 (en)
ES (1) ES2687785T3 (en)
WO (1) WO2015086119A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10814365B2 (en) 2018-06-13 2020-10-27 Novelis Inc. Systems and methods for cooling a roll in metal processing
US10953447B2 (en) 2018-06-13 2021-03-23 Novelis Inc. Systems and methods for containing viscous materials in roll processing
US11007557B2 (en) 2018-06-13 2021-05-18 Novelis Inc. Systems and methods for removing viscous materials in metal article processing

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2537162B (en) 2015-04-10 2017-04-19 Primetals Technologies Austria GmbH Work roll cooling apparatus and method
DE102016207138B4 (en) * 2016-04-27 2018-05-30 Sms Group Gmbh Method and device for cooling a tool

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002087803A1 (en) * 2001-05-01 2002-11-07 Air Products And Chemicals, Inc. A process and roll stand for cold rolling of a metal strip
WO2009032688A1 (en) * 2007-08-28 2009-03-12 Air Products And Chemicals, Inc. Apparatus and method for providing condensation-and frost-free surfaces on cryogenic components
GB2466458A (en) * 2008-12-19 2010-06-23 Siemens Vai Metals Tech Ltd Rolling Mill Temperature Control
WO2012110241A1 (en) * 2011-02-17 2012-08-23 Linde Aktiengesellschaft Nozzle header

Family Cites Families (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1069892A (en) * 1913-04-17 1913-08-12 William A Medlin Wire-fence stretcher.
BE755842A (en) * 1968-07-19 1971-02-15 Masch & Werkzeugbau Gmbh ROLLER CAGE AND CHANGING DEVICE FOR WORKING CYLINDERS OF A CAGE
KR930000465B1 (en) * 1985-05-17 1993-01-21 가부시기가이샤 히다찌세이사꾸쇼 Method and apparatus for cooling rolling mill rolls
GB8514598D0 (en) * 1985-06-10 1985-07-10 Davy Mckee Poole Lubrication of rolling mills
DE3675985D1 (en) * 1985-06-10 1991-01-17 Davy Mckee Poole LUBRICATION OF ROLLING MILLS.
US4899904A (en) * 1988-10-03 1990-02-13 Dooley Leslie T Beverage can cartridge
US5535884A (en) * 1994-07-15 1996-07-16 Sony Corporation Disk carrying case with sliding circular cover
USD434268S (en) * 2000-01-27 2000-11-28 Sunnex Products Limited Rectangular chafing dish
USD434594S (en) * 2000-01-27 2000-12-05 Sunnex Products Limited Oval chafing dish
USD434267S (en) * 2000-01-27 2000-11-28 Sunnex Products Limited Round chafing dish
ATE271749T1 (en) * 2001-03-09 2004-08-15 Inducs A G DEVICE AND METHOD FOR KEEPING FOOD WARM
US6872920B2 (en) * 2001-07-09 2005-03-29 Robert Haber User sensing chafing dish
US6698334B2 (en) * 2002-01-18 2004-03-02 Legion Industries, Inc. Chafer
FR2844256B1 (en) * 2002-09-06 2005-05-13 Vaslin Bucher DOOR DEVICE FOR CONTAINER UNDER PRESSURE AND CONTAINER COMPRISING SUCH A DEVICE
JP3096524U (en) * 2003-03-18 2003-09-26 博志 久保 mouse
US20140054292A1 (en) * 2006-04-24 2014-02-27 Converter Manufacturing, Inc. Multilayer Thermoformable Materials and Sanitary Food Containers Made Therefrom
US20110036555A1 (en) * 2007-08-28 2011-02-17 Air Products And Chemicals, Inc. Method and apparatus for discharging a non-linear cryogen spray across the width of a mill stand
US7922027B2 (en) * 2007-09-11 2011-04-12 Wasatch Manufacturing, Llc Food pan having elastomeric heat and scratch resistant protective flange gasket
DE102009053073A1 (en) * 2009-03-03 2010-09-09 Sms Siemag Aktiengesellschaft Method and cooling device for cooling the rolls of a roll stand
US20130142975A1 (en) * 2011-06-02 2013-06-06 Converter Manufacturing, Llc Barrier Film for Use in Multilayer Thermoformable Materials and Shaped Articles and Containers Made Therefrom
DE102011104735A1 (en) * 2011-06-16 2012-12-20 Sms Siemag Ag Method and device for cooling a work roll
DE102012202340A1 (en) * 2011-12-23 2013-06-27 Sms Siemag Ag Method and device for cooling rolls
CN202377266U (en) * 2011-12-28 2012-08-15 哈尔滨理工大学 Aluminum silicon alloy rolling roll cooling device
DE102012201496A1 (en) * 2012-02-02 2013-08-08 Sms Siemag Ag Device for directing a flow for cooling a roll or a metal strip
US20150282547A1 (en) * 2012-03-23 2015-10-08 Ahmed Imad Dhia Covering Assembly for a Helmet
DE102012216570A1 (en) * 2012-05-11 2013-11-14 Sms Siemag Ag Device for cooling rolls
CN203076332U (en) * 2012-12-25 2013-07-24 张店钢铁总厂 Water spraying pipe for cooling of roller
US10117513B1 (en) * 2013-10-17 2018-11-06 Grant M. J. Tolentino Portable chafing and serving table
US20190090688A1 (en) * 2017-09-25 2019-03-28 Austin Wilson Cooking devices

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002087803A1 (en) * 2001-05-01 2002-11-07 Air Products And Chemicals, Inc. A process and roll stand for cold rolling of a metal strip
WO2009032688A1 (en) * 2007-08-28 2009-03-12 Air Products And Chemicals, Inc. Apparatus and method for providing condensation-and frost-free surfaces on cryogenic components
GB2466458A (en) * 2008-12-19 2010-06-23 Siemens Vai Metals Tech Ltd Rolling Mill Temperature Control
WO2012110241A1 (en) * 2011-02-17 2012-08-23 Linde Aktiengesellschaft Nozzle header

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10814365B2 (en) 2018-06-13 2020-10-27 Novelis Inc. Systems and methods for cooling a roll in metal processing
US10953447B2 (en) 2018-06-13 2021-03-23 Novelis Inc. Systems and methods for containing viscous materials in roll processing
US11007557B2 (en) 2018-06-13 2021-05-18 Novelis Inc. Systems and methods for removing viscous materials in metal article processing

Also Published As

Publication number Publication date
JP6516745B2 (en) 2019-05-22
EP2881186A1 (en) 2015-06-10
CN106163683B (en) 2018-05-15
EP3079841A1 (en) 2016-10-19
ES2687785T3 (en) 2018-10-29
JP2017501882A (en) 2017-01-19
BR112016013035A2 (en) 2017-09-19
CN106163683A (en) 2016-11-23
KR20160096165A (en) 2016-08-12
US20160303626A1 (en) 2016-10-20
EP3079841B1 (en) 2018-07-18

Similar Documents

Publication Publication Date Title
EP3079841B1 (en) Method and apparatus to isolate the cold in cryogenic equipment
EP2675580B1 (en) Nozzle header
JP4040979B2 (en) Cold rolling method and rolling stand for metal strip
JP5752046B2 (en) Apparatus for rolling metal foil or strip and method for controlling the shape of a metal strip or foil during rolling
ES2605829T3 (en) Procedure and device to avoid surface defects caused by zinc dust in a continuous galvanizing process of strapping
WO1986002568A1 (en) Fireproof cabinet system for electronic equipment
US7197883B2 (en) Cooling or heating with multi-pass fluid flow
EP2193307B1 (en) Apparatus and method for providing condensation-and frost-free surfaces on cryogenic components
EP3224509B1 (en) A seal for use in cryogenic applications
WO2011126581A2 (en) System and method for delivering cryogenic fluid to a spray head used to cool an enclosed space
ES2623037T3 (en) Pre-cooling system with internal pilot regulation
ES2253645T3 (en) REFRIGERATION PROCEDURE AND INSTALLATION OF A MOVING METAL BAND.
JP5693284B2 (en) Condensate water treatment equipment for refrigerated warehouses
US20220008246A1 (en) Systemic cryotherapy device with engine room assembly
EP3444547B1 (en) Food freezer and corresponding method of exhausting freezing gas
JP2000161828A (en) Cooling facility for magnetic sheet

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14803052

Country of ref document: EP

Kind code of ref document: A1

REEP Request for entry into the european phase

Ref document number: 2014803052

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2014803052

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 15101484

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: IDP00201603810

Country of ref document: ID

ENP Entry into the national phase

Ref document number: 2016538089

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20167018294

Country of ref document: KR

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2016124587

Country of ref document: RU

Kind code of ref document: A

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112016013035

Country of ref document: BR

ENP Entry into the national phase

Ref document number: 112016013035

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20160607