EP2078181A2 - Controlling curtain opening system in continuous furnaces - Google Patents

Controlling curtain opening system in continuous furnaces

Info

Publication number
EP2078181A2
EP2078181A2 EP07852725A EP07852725A EP2078181A2 EP 2078181 A2 EP2078181 A2 EP 2078181A2 EP 07852725 A EP07852725 A EP 07852725A EP 07852725 A EP07852725 A EP 07852725A EP 2078181 A2 EP2078181 A2 EP 2078181A2
Authority
EP
European Patent Office
Prior art keywords
light
curtain
photo cell
opening
passing
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP07852725A
Other languages
German (de)
French (fr)
Other versions
EP2078181A4 (en
Inventor
Mircea Stefan Stanescu
Paul Francis Stratton
Leontin Nicolae Druga
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Messer LLC
Original Assignee
Linde Inc
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 Inc filed Critical Linde Inc
Publication of EP2078181A2 publication Critical patent/EP2078181A2/en
Publication of EP2078181A4 publication Critical patent/EP2078181A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D99/00—Subject matter not provided for in other groups of this subclass
    • F27D99/0073—Seals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D19/00—Arrangements of controlling devices

Definitions

  • the present invention relates to a system in a heating furnace, and more particularly, controlling curtain opening system in a continuous furnaces.
  • Metal wire mesh, chain curtains and curtains made of Refrasil (tape and cordage) or other refractory materials are used in continuous furnaces.
  • Box curtains containing a metal wire mesh (or metal chain) and several Refrasil, or Nextel 312 tape or cordage curtains located on the cold side of the metal mesh curtain are increasingly used in continuous furnaces.
  • various designs of box curtains are easier to visit, adjust, maintain and replace than the conventional curtains that are separately installed in continuous furnaces.
  • a curtain box installed at the charge end, discharge end and between hot zone and cooling zone or between different zones, containing several curtains is easy to visit, maintain, adjust and replace, by opening a very well sealed cup on the top of the box.
  • curtain boxes or curtains are installed at the charge end opening and discharge end opening, they significantly contribute to reduce air ingress into the furnace, reduce protective atmosphere flow rate and reduce heat losses through the charge and discharge end openings
  • the curtain boxes or curtains installed at the discharge end of the continuous furnace do not have metal curtains and the materials could be less expensive because the working temperature is lower, such as to a temperature of less than about 650 0 F
  • curtain boxes or curtains are installed at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone), they significantly contribute to reduce heat losses from the hot zone into the cooling zone, separate the atmosphere of the hot zone from that in the cooling zone (which require a higher H 2 /H 2 O ratio at lower temperature to protect against oxidation of metals) and permits a higher cooling rate, shortening the cooling time and, in many cases, the cycle time
  • cooling from the annealing temperature must be rapid, no more than approximately 3 minutes in cooling from about 1600 0 F to about 800 0 F If cooling (zone) does not provide a cooling rate sufficient to prevent carbide precipitation, maximum corrosion resistance will not be obtained
  • This invention is directed to a controlling curtain opening system in a continuous furnace which comprises a light-photo cell eye system positioned in front of a curtain box, a series of light beams casting across the light-photo cell eye system there through, which measures the dimension of a metal substance passing across the series of light beams
  • This invention is also directed to a method of controlling the curtain in a continuous furnace, the method comprises a) positioning a light-photo cell eye system in front of a curtain box, in which a series of light beams casts across the light-photo cell eye system there through, b) measuring the dimension of a metal substance passing across the series of light beams, and c) adjusting the opening of the curtain using the measurements from the dimension of the metal substance
  • FIG 1 is a perspective view of the metal assembly in a controlled atmosphere as embodied in this invention
  • FIG 2 is a perspective view of the moving products relative to the laser photo cell eye system
  • Product such as steel tubes, steel bars, etc , entangling with curtains made of Refrasil or Nextel 312, product scratching with curtains made of metal wire mesh or metal chain could be removed by manual or automatic adjustment of curtains opening, depending on the height of the product.
  • An automatic adjustment of curtains opening system could be installed in continuous furnaces, including belt, humpback, roller hearth, and pusher continuous furnaces using a plurality of gases including N 2 and H 2 , Ar and He, or substantially pure H 2 to anneal different products.
  • gases including N 2 and H 2 , Ar and He, or substantially pure H 2 to anneal different products.
  • the products include steel and stainless steel tubes, bars, stainless steel sinks, etc.
  • FIG. 1 The automatic curtain opening adjustment system of this invention depending on the height of the products, in continuous furnaces, is showed in FIG. 1 .
  • the system automatically adjusts the opening of curtains in the curtain boxes installed at the charge vestibule, discharge vestibule and at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone).
  • a source of light or a laser on one side of the charging (loading) table (the light-photo cell eye system) and photo-electric cells on the other side of the charging table (the light-photo cell eye system) would sense the height of the moving product or group of products (in FIG. 2 shown as steel bars or steel tubes).
  • the signal is captured by a processor which will increase or decrease curtains opening through an electro-mechanical system (electrical servo-motor and gears system or screw system). Opening of curtains in a curtain box could be adjusted automatically by a program in addition to a laser (or light)-photo cell eye. system, depending on the height of the product.
  • electro-mechanical system electrical servo-motor and gears system or screw system. Opening of curtains in a curtain box could be adjusted automatically by a program in addition to a laser (or light)-photo cell eye. system, depending on the height of the product.
  • FIG. 1 shows the continuous furnace with automatic adjustment of curtains opening depending on the height of the moving products.
  • the moving products is a metal substance.
  • the system 100 is provided where a metal substances is passed through a changing table 1 10 on which a laser- photo cell eye system 1 15 is placed. The metal then passes through a first curtain box 120, a charge vestibule 125, followed by hot zone 130, a second curtain box 135 and a cooling zone 140 After the cooling zone, the metal passes through a discharge vestibule 145 followed by a third curtain box 150
  • FIG 2 shows a laser photo cell eye system measuring the height of the product and automatically adjusting the opening of the curtains in the curtain box
  • the beam of light 210 measures the height of the product 220 and automatically adjusts the opening of the curtains in the curtain box
  • the curtain opening system of this invention eliminate or significantly reduce incidents of product (steel tubes, steel bars, etc ) entangling with curtains made of Refrasil or Nextel 312 and product scratching with curtains made of metal wire mesh or metal chain
  • the curtain opening system of this invention reduces consumption of fuel (ex natural gas) used for heating the furnace by 10%-22%
  • the curtain opening system of this invention reduces the consumption of the gas(es) used for the atmosphere by 10%- 20% This aspect contributes to reducing the cooling time
  • the curtain opening system of this invention is easy to build, install and could work for groups of moving products of different heights Each group of moving products must have the same height
  • the curtain opening system of this invention actuates a curtain box, which is installed at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone), could contribute to a higher rate of cooling by significantly reducing heat losses from hot zone into the cooling zone
  • the products made of austenitic stainless steels and other materials proceeds with cooling from the annealing temperature that must be rapid, and no more than approximately 3 minutes in cooling from about 1600 0 F to about 800 0 F).
  • the curtain opening system of this invention provides for laser (or light)-photo cell eye system could verify the settings of the program for a given product, to ensure the correct setting of the curtain opening.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat Treatment Of Articles (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Tunnel Furnaces (AREA)

Abstract

This invention is directed to a controlling curtain opening system in a continuous furnace which comprises a laser photo cell eye system situated in front of the curtain box. The laser photo cell eye system comprises a plurality of laser beams to monitor and adjust to the height of a moving products passing there through.

Description

CONTROLLING CURTAIN OPENING SYSTEM IN CONTINUOUS
FURNACES
CROSS-REFERENCE TO RELATED APPLICATION
[001] The present application claims priority from US Provisional Patent Application 60/829,163 riled October 12, 2006.
FIELD OF THE INVENTION
[002] The present invention relates to a system in a heating furnace, and more particularly, controlling curtain opening system in a continuous furnaces.
BACKGROUND OF THE INVENTION
[003] Metal wire mesh, chain curtains and curtains made of Refrasil (tape and cordage) or other refractory materials are used in continuous furnaces. Box curtains containing a metal wire mesh (or metal chain) and several Refrasil, or Nextel 312 tape or cordage curtains located on the cold side of the metal mesh curtain are increasingly used in continuous furnaces. Also, various designs of box curtains are easier to visit, adjust, maintain and replace than the conventional curtains that are separately installed in continuous furnaces. A curtain box installed at the charge end, discharge end and between hot zone and cooling zone or between different zones, containing several curtains is easy to visit, maintain, adjust and replace, by opening a very well sealed cup on the top of the box. Such an assembly (curtain box or a box with curtains) will separate the temperature zones and atmosphere composition in a continuous furnace much better than the conventional curtains and will be easier to visit, maintain, adjust and replace. [004] If curtain boxes or curtains are installed at the charge end opening and discharge end opening, they significantly contribute to reduce air ingress into the furnace, reduce protective atmosphere flow rate and reduce heat losses through the charge and discharge end openings In continuous furnaces used in annealing of steel products, the curtain boxes or curtains installed at the discharge end of the continuous furnace do not have metal curtains and the materials could be less expensive because the working temperature is lower, such as to a temperature of less than about 650 0F
[005] If curtain boxes or curtains are installed at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone), they significantly contribute to reduce heat losses from the hot zone into the cooling zone, separate the atmosphere of the hot zone from that in the cooling zone (which require a higher H2/H2O ratio at lower temperature to protect against oxidation of metals) and permits a higher cooling rate, shortening the cooling time and, in many cases, the cycle time In the case of austenitic stainless steels and other materials, cooling from the annealing temperature must be rapid, no more than approximately 3 minutes in cooling from about 1600 0F to about 800 0F If cooling (zone) does not provide a cooling rate sufficient to prevent carbide precipitation, maximum corrosion resistance will not be obtained
[006] It is therefore desirable in the art for an automatic curtain opening system that reduces incidents of product entangling and reduces fuel consumption
SUMMARY OF THE INVENTION
[007] This invention is directed to a controlling curtain opening system in a continuous furnace which comprises a light-photo cell eye system positioned in front of a curtain box, a series of light beams casting across the light-photo cell eye system there through, which measures the dimension of a metal substance passing across the series of light beams
[008] This invention is also directed to a method of controlling the curtain in a continuous furnace, the method comprises a) positioning a light-photo cell eye system in front of a curtain box, in which a series of light beams casts across the light-photo cell eye system there through, b) measuring the dimension of a metal substance passing across the series of light beams, and c) adjusting the opening of the curtain using the measurements from the dimension of the metal substance
BRIEF DESCRIPTION OF THE DRAWINGS
[009] While the specification concludes with claims distinctly pointing the subject matter that applicants regard as their invention, it is believed that the invention would be better understood when taken in connection with the accompanying drawings in which FIG 1 is a perspective view of the metal assembly in a controlled atmosphere as embodied in this invention, and FIG 2 is a perspective view of the moving products relative to the laser photo cell eye system
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0010] Selection of curtain material and adjustment of curtaιn(s) should take into account the danger of Refrasil or Nextel 312 curtain and the product scratching of metal curtains (chains and wire mesh) The curtains should have an opening that avoids entangling and scratching of moving products
[0011] Product, such as steel tubes, steel bars, etc , entangling with curtains made of Refrasil or Nextel 312, product scratching with curtains made of metal wire mesh or metal chain could be removed by manual or automatic adjustment of curtains opening, depending on the height of the product.
[0012] An automatic adjustment of curtains opening system could be installed in continuous furnaces, including belt, humpback, roller hearth, and pusher continuous furnaces using a plurality of gases including N2 and H2, Ar and He, or substantially pure H2 to anneal different products. The products include steel and stainless steel tubes, bars, stainless steel sinks, etc.
[0013] The automatic curtain opening adjustment system of this invention depending on the height of the products, in continuous furnaces, is showed in FIG. 1 . The system automatically adjusts the opening of curtains in the curtain boxes installed at the charge vestibule, discharge vestibule and at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone). A source of light or a laser on one side of the charging (loading) table (the light-photo cell eye system) and photo-electric cells on the other side of the charging table (the light-photo cell eye system) would sense the height of the moving product or group of products (in FIG. 2 shown as steel bars or steel tubes). The signal is captured by a processor which will increase or decrease curtains opening through an electro-mechanical system (electrical servo-motor and gears system or screw system). Opening of curtains in a curtain box could be adjusted automatically by a program in addition to a laser (or light)-photo cell eye. system, depending on the height of the product.
[0014] FIG. 1 shows the continuous furnace with automatic adjustment of curtains opening depending on the height of the moving products. The moving products is a metal substance. The system 100, is provided where a metal substances is passed through a changing table 1 10 on which a laser- photo cell eye system 1 15 is placed. The metal then passes through a first curtain box 120, a charge vestibule 125, followed by hot zone 130, a second curtain box 135 and a cooling zone 140 After the cooling zone, the metal passes through a discharge vestibule 145 followed by a third curtain box 150
[0015] FIG 2 shows a laser photo cell eye system measuring the height of the product and automatically adjusting the opening of the curtains in the curtain box The beam of light 210 measures the height of the product 220 and automatically adjusts the opening of the curtains in the curtain box
[0016] In an embodiment, the curtain opening system of this invention eliminate or significantly reduce incidents of product (steel tubes, steel bars, etc ) entangling with curtains made of Refrasil or Nextel 312 and product scratching with curtains made of metal wire mesh or metal chain
[0017] In an embodiment, the curtain opening system of this invention reduces consumption of fuel (ex natural gas) used for heating the furnace by 10%-22%
[0018] In an embodiment, the curtain opening system of this invention reduces the consumption of the gas(es) used for the atmosphere by 10%- 20% This aspect contributes to reducing the cooling time
[0019] In an embodiment, the curtain opening system of this invention is easy to build, install and could work for groups of moving products of different heights Each group of moving products must have the same height
[0020] In an embodiment, the curtain opening system of this invention actuates a curtain box, which is installed at the beginning of the cooling zone (or in the intermediary zone or at the end of the hot zone), could contribute to a higher rate of cooling by significantly reducing heat losses from hot zone into the cooling zone In an embodiment, the products made of austenitic stainless steels and other materials, proceeds with cooling from the annealing temperature that must be rapid, and no more than approximately 3 minutes in cooling from about 1600 0F to about 800 0F).
[0021] In an embodiment, the curtain opening system of this invention provides for laser (or light)-photo cell eye system could verify the settings of the program for a given product, to ensure the correct setting of the curtain opening.
[0022] It will be understood that the embodiment(s) described herein are merely exemplary, and that one skilled in the art may make variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention as described hereinabove. Further, all embodiments disclosed are not necessarily in the alternative, as various embodiments of the invention may be combined to provide the desired result.

Claims

What is claimed is
1 A controlling curtain opening system in a continuous furnace which comprises a light-photo cell eye system positioned in front of a curtain box, a series of light bedims casting across the light-photo cell eye system there through, which measures the dimension of a metal object passing across the series of light beams
2 The controlling curtain opening system of claim 1 wherein the light-photo cell eye system comprises a source of light on one and a photoelectric cell on the other side there through
3 The controlling curtain opening system of claim 1 wherein the light-photo cell eye system comprises a plurality of light beams to monitor and adjust to the height of a moving products passing there through
4 The controlling curtain opening system of claim 3 wherein a signal processor processes signals from the light beams that passes the metal objects
5 The controlling curtain opening system of claim 3 wherein the light-photo cell eye system adjusts the opening of curtains in the curtain box by a electro-mechanical system
6 The controlling curtain opening system of claim 5 wherein the electro-mechanical system comprises an electrical servo-motor and gear system or screw system
7 The controlling curtain opening system of claim 1 wherein the light beams are laser beams
8. A method of controlling the curtain in a continuous furnace, the method comprises a) positioning a light-photo cell eye system in front of a curtain box, in which a series of light beams casts across the light-photo cell eye system there through, b) measuring the dimension of a metal substance passing across the series of light beams, and c) adjusting the opening of the curtain using the measurements from the dimension of the metal substance.
9. The method of claim 8 which comprises passing a light source from one side of the light-photo cell eye system to photo-electric cell on the other side of the light-photo cell eye system.
10. The method of claim 8 which comprises passing a plurality of light beams to monitor and adjust to the height of a moving products passing there through.
1 1 . The method of claim 8 which further comprises passing signals resulting from the passing a plurality of light beams to monitor and adjust to the height of a moving products passing the light-photo cell eye system to a signal processor.
12. The method of claim 8 which further comprises adjusting the opening of curtains in the curtain box by an electro-mechanical system triggered from the signal processor.
13. The method of claim 12 wherein the electro-mechanical system comprises an electrical servo-motor and gear system or screw system.
14. The method of claim 8 wherein the light beams are laser beams.
EP07852725A 2006-10-12 2007-10-12 Controlling curtain opening system in continuous furnaces Withdrawn EP2078181A4 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US82916706P 2006-10-12 2006-10-12
US11/974,045 US20080271653A1 (en) 2006-10-12 2007-10-11 Controlling curtain opening system in continuous furnaces
PCT/US2007/021900 WO2008045562A2 (en) 2006-10-12 2007-10-12 Controlling curtain opening system in continuous furnaces

Publications (2)

Publication Number Publication Date
EP2078181A2 true EP2078181A2 (en) 2009-07-15
EP2078181A4 EP2078181A4 (en) 2010-06-23

Family

ID=39283483

Family Applications (1)

Application Number Title Priority Date Filing Date
EP07852725A Withdrawn EP2078181A4 (en) 2006-10-12 2007-10-12 Controlling curtain opening system in continuous furnaces

Country Status (3)

Country Link
US (1) US20080271653A1 (en)
EP (1) EP2078181A4 (en)
WO (1) WO2008045562A2 (en)

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4997364A (en) * 1988-02-22 1991-03-05 Radiant Technology Corporation Furnace assembly for reflowing solder on printed circuit boards
DE3916178C1 (en) * 1989-05-18 1990-06-13 Mahler Dienstleistungs-Gmbh Loeten-Haerten-Anlagenbau, 7300 Esslingen, De
DE29918341U1 (en) * 1999-10-18 2001-03-01 Tassakos Charalambos Device for determining the position of measuring points of a measuring object relative to a reference system
US6278374B1 (en) * 2000-05-05 2001-08-21 Kellogg Brown & Root, Inc. Flame detection apparatus and method
DE10123241C1 (en) * 2001-05-12 2002-10-02 Sgl Carbon Ag Gas sealing system for reactor treating carbon fiber strand or tape, includes gas distribution system with nozzles and baffles near openings, to direct flow toward interior

Also Published As

Publication number Publication date
EP2078181A4 (en) 2010-06-23
US20080271653A1 (en) 2008-11-06
WO2008045562A3 (en) 2008-06-26
WO2008045562A2 (en) 2008-04-17

Similar Documents

Publication Publication Date Title
EP0181830B1 (en) Method and apparatus for heating a strip of metallic material in a continuous annealing furnace
CN105420483B (en) Continuous annealing furnace for processing aluminum alloy sheet material
TWI381142B (en) Roller hearth furnace for heating and/or thermally balancing continuously cast products of steel or alloy steels and arrangement thereof upstream of a hot strip finishing mill train
JP5655852B2 (en) Manufacturing method and manufacturing apparatus for hot-rolled steel sheet
EP2267171B1 (en) Annealing of cold rolled aluminium strip
US20120160377A1 (en) Method and device for producing a microalloyed steel, in particular a pipe steel
EP4553178A1 (en) Continuous annealing equipment, continuous annealing method, cold-rolled steel sheet manufacturing method, and plated steel sheet manufacturing method
JP5327140B2 (en) Method for cooling hot rolled steel sheet
US20080271653A1 (en) Controlling curtain opening system in continuous furnaces
CN114602971B (en) A production process of pure titanium ingot-pyrotechnical material
EP3192593A1 (en) Method for continuously casting slab containing titanium or titanium alloy
US11414736B2 (en) Production method of hot-dip galvanized steel sheet
NL2004883C2 (en) Annealing installation with m-shaped strip treatment tunnel.
DE102017113358A1 (en) Hot dip galvanizing and hot dip galvanizing
EP0835330B1 (en) Fuel boxes and a method for manufacturing fuel boxes
CN101168827A (en) A kind of heating method of light metal billet
JP5277641B2 (en) Heating furnace temperature control method
US7736583B2 (en) Gas curtain assemby for muffled continuous furnaces
JP2010149138A (en) Heat-keeping device for preventing crack in steel material
SU700253A1 (en) Automatic line for drop stamping
SU1337426A1 (en) Method of heat treatment of strip cold-rolled low-carbon steel
JP4935305B2 (en) Heating control method for continuous heating furnace
KR20190059690A (en) Apparatus for anneaing metal plate
RU2329106C1 (en) Method of heating reflecting surface of screens of heat preserving plant from initial cold condition on broad-strip mill of hot rolling
DE2019490C (en) Pusher furnace

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20090407

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR

DAX Request for extension of the european patent (deleted)
A4 Supplementary search report drawn up and despatched

Effective date: 20100527

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20101228