EP0094808B1 - Procédé pour réduire le collage des tôles en acier pendant le recuit en caisse - Google Patents
Procédé pour réduire le collage des tôles en acier pendant le recuit en caisse Download PDFInfo
- Publication number
- EP0094808B1 EP0094808B1 EP83302724A EP83302724A EP0094808B1 EP 0094808 B1 EP0094808 B1 EP 0094808B1 EP 83302724 A EP83302724 A EP 83302724A EP 83302724 A EP83302724 A EP 83302724A EP 0094808 B1 EP0094808 B1 EP 0094808B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- sheet
- rinse
- annealing
- concentration
- ppm
- 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.)
- Expired
Links
- 238000000137 annealing Methods 0.000 title claims description 23
- 229910000831 Steel Inorganic materials 0.000 title claims description 19
- 239000010959 steel Substances 0.000 title claims description 19
- 238000000034 method Methods 0.000 title claims description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 238000004140 cleaning Methods 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 9
- 150000003839 salts Chemical class 0.000 claims description 6
- GMDNUWQNDQDBNQ-UHFFFAOYSA-L magnesium;diformate Chemical compound [Mg+2].[O-]C=O.[O-]C=O GMDNUWQNDQDBNQ-UHFFFAOYSA-L 0.000 claims description 5
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims description 4
- 229910019142 PO4 Inorganic materials 0.000 claims description 3
- 230000001590 oxidative effect Effects 0.000 claims description 3
- CBOCVOKPQGJKKJ-UHFFFAOYSA-L Calcium formate Chemical compound [Ca+2].[O-]C=O.[O-]C=O CBOCVOKPQGJKKJ-UHFFFAOYSA-L 0.000 claims description 2
- VSGNNIFQASZAOI-UHFFFAOYSA-L calcium acetate Chemical compound [Ca+2].CC([O-])=O.CC([O-])=O VSGNNIFQASZAOI-UHFFFAOYSA-L 0.000 claims description 2
- 239000001639 calcium acetate Substances 0.000 claims description 2
- 229960005147 calcium acetate Drugs 0.000 claims description 2
- 235000011092 calcium acetate Nutrition 0.000 claims description 2
- 229940044172 calcium formate Drugs 0.000 claims description 2
- 235000019255 calcium formate Nutrition 0.000 claims description 2
- 239000004281 calcium formate Substances 0.000 claims description 2
- UEGPKNKPLBYCNK-UHFFFAOYSA-L magnesium acetate Chemical compound [Mg+2].CC([O-])=O.CC([O-])=O UEGPKNKPLBYCNK-UHFFFAOYSA-L 0.000 claims description 2
- 239000011654 magnesium acetate Substances 0.000 claims description 2
- 235000011285 magnesium acetate Nutrition 0.000 claims description 2
- 229940069446 magnesium acetate Drugs 0.000 claims description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims description 2
- 239000010452 phosphate Substances 0.000 claims description 2
- 238000001035 drying Methods 0.000 claims 1
- 238000012360 testing method Methods 0.000 description 8
- 239000000654 additive Substances 0.000 description 7
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical class [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 6
- 229910052791 calcium Chemical class 0.000 description 6
- 239000011575 calcium Chemical class 0.000 description 6
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 5
- 239000011777 magnesium Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052749 magnesium Inorganic materials 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 150000001242 acetic acid derivatives Chemical class 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 150000004760 silicates Chemical class 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000004675 formic acid derivatives Chemical class 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 235000021317 phosphate Nutrition 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910001424 calcium ion Inorganic materials 0.000 description 1
- 239000001506 calcium phosphate Substances 0.000 description 1
- 229910000389 calcium phosphate Inorganic materials 0.000 description 1
- 235000011010 calcium phosphates Nutrition 0.000 description 1
- 150000001734 carboxylic acid salts Chemical class 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 239000007857 degradation product Substances 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000008233 hard water Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910001425 magnesium ion Inorganic materials 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 1
- 235000019341 magnesium sulphate Nutrition 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 229940099596 manganese sulfate Drugs 0.000 description 1
- 239000011702 manganese sulphate Substances 0.000 description 1
- 235000007079 manganese sulphate Nutrition 0.000 description 1
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical compound [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/68—Temporary coatings or embedding materials applied before or during heat treatment
- C21D1/70—Temporary coatings or embedding materials applied before or during heat treatment while heating or quenching
Definitions
- the present invention relates to the box-annealing of steel sheet.
- the heat treatment of cold-reduced steel sheet and strip is accomplished either in batch operations or in continuous operations.
- Batch heat treatment may be divided into two categories: (a) open-coil annealing in which a tight coil is first rewound with a suitable spacer in between each wrap of the coil to permit circulation of the furnace atmosphere between the individual wraps to hasten and improve the uniformity of heating, and (b) box annealing in which a large stationary mass of steel (either cut sheet or coils) is subjected to a comparatively longer heat treatment cycle by varying the temperature within the furnace that surrounds it. In the latter, box annealing practices, the mass of steel is slowly raised to the desired annealing temperature and soaked at such temperature for a period of to 24 hours.
- the prior art has resorted to the use of a variety of separating media such as colloidal solutions of alumina or silica, finely divided magnesium oxide particles and the formation of thin oxidizing films on the metal surface.
- the latter technique includes the use of silicate containing washing liquids aids in preventing sticking. This is a practice which has been recommended for many years by manufacturers of commercial cleaning compounds. Although many steel facilities use silicated cleaners, such use has not precluded the serious incidence of coil sticking.
- a method of box-annealing a mass of steel sheet wherein said sheet is electrolytically cleaned in a cleaning solution consisting of silicate or phosphate cleaners, or mixtures thereof, rinsed, dried, coiled and thereafter heated to an annealing temperature in a non-oxidizing atmosphere and soaked at such temperature for a time of at least one-half hour, characterized in that the solution utilized for said rinse contains calcium formate, magnesium formate, calcium acetate or magnesium acetate, or mixtures thereof, in a total concentration 1,500 to 10,000 ppm.
- a cleaning solution consisting of silicate or phosphate cleaners, or mixtures thereof
- Each pack consisted of 12 paired test specimens, with each pair separated by a stainless steel spacer. To simulate the pressure exerted by the wrapping of coils, a 15.2 lb. (6.9 kg) weight was used for each run.
- the test pack was placed in a sealed stainless steel annealing box containing a protective atmosphere of 6% H 2 -94% N 2 with a dew point controlled to minus 40°C by passing the gas mixture through a column of calcium sulfate.
- the annealing box was placed in a furnace and heated to an annealing temperature of 1250°F (677°C) in two hours.
- the residue concentration of said carboxylic acid salts will be within the range 0.5 to 1.2 mg/ft2 (5.4 to 12.9 mg/m 2 ).
- a silicated cleaner e.g. Condition 8
- an effective rinse additive such as a magnesium formate
- silicate levels on clean steel surfaces are important in their effect on sticking during annealing
- the fact that a final rinse with an appropriate additive was effective even after an initial rinse in hard water suggests that silicates, phosphates, and the thermal degradation products of calcium and magnesium formates and acetates all contribute to lower sticking during box annealing, as compared with a steel that does not have these residues on the surface.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
- Heat Treatment Of Articles (AREA)
- Chemical Treatment Of Metals (AREA)
Claims (7)
1. Procédé de recuit en caisse d'une masse de tôle d'acier, dans lequel la tôle est nettoyée électro- lytiquement dans une solution de nettoyage consistant en agents de nettoyage à base de silicate ou de phosphate ou de leurs mélanges, puis rincée, séchée, enroulée et enfin chauffée à une température de recuit en atmosphère non oxydante et maintenue à cette température pendant un temps d'au moins une demi-heure, caractérisé en ce que la solution utilisée pour le rinçage contient du formiate de calcium, de formiate de magnésium, de l'acétate de calcium ou de l'acétate de magnésium, ou leurs mélanges, à une concentration totale de 1 500 à 10 000 ppm.
2. Procédé selon la revendication 1, dans lequel la masse est une bobine de tôle d'acier, les feuilles adjacentes sont les spires de la bobine, la température de recuit est comprise entre 566 et 760°C, et le temps de maintien est inférieur à 24 heures, caractérisé en ce que le rinçage est réalisé par passage de la tôle à une vitesse de 305 à 914 m/min dans un bain de la solution de rinçage.
3. Procédé selon la revendication 2, dans lequel, après la rinçage, le séchage est poursuivi afin que pratiquement la totalité de l'eau non liée du résidu restant à la surface de la tôle soit chassée, caractérisé en ce que la concentration des sels dans la solution de rinçage est comprise entre 3 000 et 8 000 ppm.
4. Procédé selon la revendication 3, caractérisé en ce que la concentration est comprise entre 4000 et 6000 ppm.
5. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la tôle se déplace dans la solution de nettoyage entre plusieurs paires d'électrodes et est rendue cathodique dans son passage entre la dernière paire d'électrodes.
6. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la tôle séchée a une concentration des sels de 3,2 à 21,5 mg/m2 à sa surface.
7. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la tôle séchée a une concentration des sels de 5,4 à 12,9 mg/m2 à sa surface.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US37804782A | 1982-05-14 | 1982-05-14 | |
| US378047 | 1982-05-14 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0094808A1 EP0094808A1 (fr) | 1983-11-23 |
| EP0094808B1 true EP0094808B1 (fr) | 1985-11-21 |
Family
ID=23491512
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP83302724A Expired EP0094808B1 (fr) | 1982-05-14 | 1983-05-13 | Procédé pour réduire le collage des tôles en acier pendant le recuit en caisse |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0094808B1 (fr) |
| JP (1) | JPS5953635A (fr) |
| KR (1) | KR840004790A (fr) |
| AU (1) | AU1453883A (fr) |
| BR (1) | BR8302507A (fr) |
| CA (1) | CA1198708A (fr) |
| DE (1) | DE3361283D1 (fr) |
| ES (1) | ES522379A0 (fr) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7670177B2 (en) * | 2008-06-17 | 2010-03-02 | Tyco Electronics Corporation | Electrical connector having floating alignment member |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2076793A (en) * | 1935-06-05 | 1937-04-13 | American Rolling Mill Co | Process to prevent sticking during annealing |
| US2124446A (en) * | 1936-06-09 | 1938-07-19 | Texas Co | Slushing oil |
| US3919000A (en) * | 1973-06-15 | 1975-11-11 | Pennwalt Corp | Preanneal rinse process for inhibiting rust on steel strip |
| BE816851A (fr) * | 1973-07-30 | 1974-10-16 | Procede pour empecher les auto-soudures au cours du recuit de l'acier en lots | |
| GB1574323A (en) * | 1977-03-09 | 1980-09-03 | Nippon Steel Corp | Methods of cleaning metal sheets |
| BE889231A (fr) * | 1981-06-15 | 1981-10-01 | Centre Rech Metallurgique | Procede de traitement des objets metalliques |
-
1983
- 1983-05-11 CA CA000427899A patent/CA1198708A/fr not_active Expired
- 1983-05-13 ES ES522379A patent/ES522379A0/es active Granted
- 1983-05-13 AU AU14538/83A patent/AU1453883A/en not_active Abandoned
- 1983-05-13 EP EP83302724A patent/EP0094808B1/fr not_active Expired
- 1983-05-13 KR KR1019830002072A patent/KR840004790A/ko not_active Application Discontinuation
- 1983-05-13 JP JP58082889A patent/JPS5953635A/ja active Pending
- 1983-05-13 BR BR8302507A patent/BR8302507A/pt unknown
- 1983-05-13 DE DE8383302724T patent/DE3361283D1/de not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| ES8404713A1 (es) | 1984-05-01 |
| KR840004790A (ko) | 1984-10-24 |
| DE3361283D1 (en) | 1986-01-02 |
| AU1453883A (en) | 1983-11-17 |
| JPS5953635A (ja) | 1984-03-28 |
| CA1198708A (fr) | 1985-12-31 |
| BR8302507A (pt) | 1984-01-17 |
| EP0094808A1 (fr) | 1983-11-23 |
| ES522379A0 (es) | 1984-05-01 |
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Legal Events
| Date | Code | Title | Description |
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| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
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| 26N | No opposition filed | ||
| BERE | Be: lapsed |
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| GBPC | Gb: european patent ceased through non-payment of renewal fee |