EP0236354B1 - Procede de decapage acide de produits en acier inoxydable - Google Patents
Procede de decapage acide de produits en acier inoxydable Download PDFInfo
- Publication number
- EP0236354B1 EP0236354B1 EP19860904835 EP86904835A EP0236354B1 EP 0236354 B1 EP0236354 B1 EP 0236354B1 EP 19860904835 EP19860904835 EP 19860904835 EP 86904835 A EP86904835 A EP 86904835A EP 0236354 B1 EP0236354 B1 EP 0236354B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- bath
- pickling
- stainless steel
- pickled
- process according
- 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
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 38
- 239000010935 stainless steel Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000005530 etching Methods 0.000 title abstract 6
- 239000002253 acid Substances 0.000 title description 7
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 24
- 238000002347 injection Methods 0.000 claims abstract description 23
- 239000007924 injection Substances 0.000 claims abstract description 23
- 230000003647 oxidation Effects 0.000 claims abstract description 19
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 claims abstract description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 11
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims abstract description 5
- 238000005554 pickling Methods 0.000 claims description 94
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 35
- 230000008569 process Effects 0.000 claims description 24
- 238000007792 addition Methods 0.000 claims description 10
- 239000007800 oxidant agent Substances 0.000 claims description 7
- 230000001590 oxidative effect Effects 0.000 claims description 7
- 238000004064 recycling Methods 0.000 claims description 4
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 229910000963 austenitic stainless steel Inorganic materials 0.000 claims description 3
- 230000000295 complement effect Effects 0.000 claims description 3
- 239000012286 potassium permanganate Substances 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 2
- 230000001105 regulatory effect Effects 0.000 claims 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 claims 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 abstract description 3
- 229910017604 nitric acid Inorganic materials 0.000 abstract description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 50
- 229910052742 iron Inorganic materials 0.000 description 14
- 239000000243 solution Substances 0.000 description 14
- 238000012360 testing method Methods 0.000 description 13
- 238000004090 dissolution Methods 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 239000010802 sludge Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- SHXXPRJOPFJRHA-UHFFFAOYSA-K iron(iii) fluoride Chemical compound F[Fe](F)F SHXXPRJOPFJRHA-UHFFFAOYSA-K 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 3
- 230000001172 regenerating effect Effects 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 238000005273 aeration Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000001186 cumulative effect Effects 0.000 description 2
- 238000007922 dissolution test Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 150000002826 nitrites Chemical class 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 230000003252 repetitive effect Effects 0.000 description 2
- 229910021653 sulphate ion Inorganic materials 0.000 description 2
- 229910015475 FeF 2 Inorganic materials 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- GQPLMRYTRLFLPF-UHFFFAOYSA-N nitrous oxide Inorganic materials [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 230000001502 supplementing effect Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/086—Iron or steel solutions containing HF
Definitions
- the field of the present invention is that of surface treatments and more specifically of the acid pickling of stainless steel products.
- the acid pickling of stainless steels is usually carried out with fluonitric baths, in which the use of nitric acid has the disadvantage of causing the formation of nitrous vapors polluting the atmosphere and soluble nitrates polluting the liquid effluents.
- J.H.G. MONYPENNY indicates pp. 183 - 184 that, to minimize the problem of vapors from fluonitric pickling baths, stainless steel sheets were used for pickling baths containing 6 to 12% of 90% solution of ferric sulfate and 1.5 to 3% hydrofluoric acid and this for example at 70 - 80 ° C for descaling a hot rolled sheet.
- the initial concentration of ferric iron in the preceding baths is thus approximately 16.5 to 33 g / I.
- the tests of the applicant have shown that, when successive samples of stainless steel sheet are scoured in such baths, the speed and the quality of the pickling deteriorate rapidly. These acid pickling baths are therefore not satisfactory as such for serial or continuous pickling of stainless steel products.
- document DE-C-899 890 published in 1953, describes a process for regenerating an HF / Fe 3+ pickling bath of steels by adding nitrites, part of these nitrites being able to be replaced by l oxygen introduced into the bath by means of air injection.
- document GE-A-2 000 196 describes a process for controlling the composition of a pickling bath for stainless steels containing HF and ferric sulphate, in which the REDOX potential of the bath is maintained within a chosen interval by addition of hydrogen peroxide and sulfuric acid.
- one or more pickling baths are used, initially containing HF 10 at 35 g / I and Fe 3+ > 20 g / I, and during the pickling operation (s) the Fe 3+ content of this bath or these baths is kept at least 20 g / I thanks to an oxidation of the bath or baths comprising one or more air injections total flow between 1 and 8 Nm 3 per m 2 of pickled stainless steel and per hour of pickling of each pickled surface element. Air injections of greater total flow have proved to be of no interest, the saturation of the bath with oxygen in the air being undoubtedly reached and the additional air flows no longer apparently serving only to stir the bath, and this in a way eventually excessive.
- the concentration of ferric iron in the bath can be calculated as the difference between the concentration of total iron, determined for example by atomic absorption, and the concentration of Fe2 + measured by its oxidation to Fe 3+ in the presence of permanganate KMn0 4 .
- Adequate aeration of the pickling bath typically by air injection, allows the quality of pickling to be maintained during successive pickling or continuous pickling of stainless steel products by regenerating Fe 3+ .
- the total volume of air injected into the pickling bath essentially depends on the amount of pickled stainless steel, which quantity itself is proportional to the pickled surface and the duration of pickling of this surface.
- the total flow rate of air injected into the pickling bath of the invention is typically between 2 and 5 Nm 3 per m 2 d '' pickled stainless steel and per hour of pickling of each pickled surface element. So that the pickling bath is adequately aerated, it is then advisable to inject a good part of this volume of air, typically typically at least half of this volume, with nozzles directed towards the bottom of the bath at the lower half. from this bath.
- the injected air is preferably preheated to a temperature close to that of the bath, ie typically between 35 and 60 ° C.
- the refills are carried out as usual, and, rather than determining the concentration of the bath, it is practical to determine the REDOX potential of the bath and to set it between 0 and +800 mV and preferably between +100 and +300 mV by acting if necessary on the oxidation of the bath.
- the reference REDOX potential is chosen according to the grade and surface condition of the strip and readjusted, if necessary, based on surface condition observations after pickling.
- the REDOX potential is measured between a platinum electrode and an Ag / AgCI reference electrode or with fixed potential, reproducible and with zero irreversibility power.
- a device for measuring this REDOX potential can be suitably sealed so as to allow continuous measurements in the bath.
- an oxidation means temporarily and / or locally supplementing the action of the air to return more quickly to the desired Fe 3+ concentration or at the set REDOX potential, so as to find good pickling.
- strong oxidant for example hydrogen peroxide or potassium permanganate, is then used as a complementary means of oxidizing the bath. It is still possible in certain cases to introduce an oxygen injection or to increase the air flow.
- the Applicant has found that it was then possible to modify the solubility of the sludge, or precipitated from the spent bath, by adjusting the REDOX potential of the bath during pickling.
- the "sludge" is not very soluble when the bath has been adjusted below +100 mV or above +300 to 350 mV, and their solubility is greatly improved between +100 mV and +300 mV, and more particularly between +190 mV and +260 mV, the optimal bath control being 220 ⁇ 20 mV.
- ferric fluoride or ferric sulphate or ferric chloride For the preparation of the pickling bath, use is generally made of ferric fluoride or ferric sulphate or ferric chloride, with a ferric iron concentration of between 20 and 40 g / l, with a preference for ferric fluoride, so as to have only one acid radical in the bath.
- This air injection here was of the order of 1 1 / min, that is to say very in excess with respect to the useful flow rate.
- Consistent pickling tests were carried out in the laboratory of several hundred samples similar to the samples in test series No. 1, always in the same pickling solution of initial composition HF 20 g / I, with periodic recharging. on the one hand in order to conserve 20 g / I and on the other hand in H 2 0 2 to the minimum necessary taking into account the concentration of iron in the solution, this with injection of air into the pickling bath.
- the total dissolved iron concentration, the cumulative consumption of and the cumulative consumption of hydrogen peroxide H 2 0 2 were respectively monitored as a function of the number of pickled samples, each for 2 min. It has been observed that up to 275 to 300 pickled samples, corresponding to 25 to 27 g / I of dissolved iron, the consumption of HF and H 2 0 2 are fairly high and roughly proportional to the number of pickled samples, and beyond that consumption of HF and H 2 0 2 becomes very low. Thus, when the concentration of dissolved iron becomes greater than 25 g / l, the consumption of concentrated HF at 70% jumps surprisingly from 7 ml per 100 pickled samples to 0.3 ml per 100 pickled samples.
- the oxygen in the air injected into the bath acts as an ion regenerator (Fe 3 +) according to the equilibrium reaction (C) already indicated, by moving this equilibrium in direction 3 of the formation of Fe 3 +, the pH of the solution being favorable and of the order of 2 as a result of the HF concentration. If this reaction (C) is adjusted so that it allows a regeneration of Fe2 + to Fe 3+ fast enough to always have Fe 3+ > 20 to 25 g / I, there is almost no need for H 2 0 2 . And consumption is surprisingly much lower than for lower concentrations of iron and therefore Fe 3 +.
- the bath contained 20 g / l of and initially 25 g / l of Fe 3+ , coming from ferric fluoride dissolved in the bath. Air was injected into the bath mainly with nozzles spaced 2 to 3 m apart and directed downwards with an inclination of 15 ° with respect to the vertical, the air being released at the end of these nozzles towards the bottom of the tray and 15 cm from this bottom.
- the total flow rate of air injected into the bath was 100 Nm 3 / h, 2/3 of which towards the bottom and in the vicinity of this bottom with the nozzles which have just been described.
- the bath temperature was 40 to 45 ° C. The bath was run by measuring and adjusting its REDOX potential above +150 mV.
- the total flow of injected air is therefore: or 3.1 Nm 3 per m 2 of pickled stainless steel and per hour of pickling of each pickled surface element.
- the baths contained 25 g / I of HF and initially 20 g / I of Fe 3 +. Air was injected with nozzles with a layout similar to that of Example 1 with a total flow rate for each tank of 80 m 3 / h and a pressure of 0.2 MPa, ie a flow rate of approximately 160 Nm 3 / h.
- the bath temperature was 50 to 55 ° C.
- the bath was controlled by measuring and adjusting its REDOX potential above +200 mV. Additions of hydrogen peroxide were planned as a complementary means of oxidation to readjust the REDOX potential when it had become too low. We were able to operate for periods of several days without using this additional oxidation means and while retaining a potential of +200 to +300 mV with a good quality of pickling.
- the injected air flow here is 4 Nm 3 per m 2 of pickled stainless steel and per hour of pickling of each pickled surface element.
- the complex formed is of the FeF 3 , 3H 2 0 type. It has been found that this compound was soluble neither in water at 20 ° C. nor in an aqueous solution of 20 g of per liter at 20 ° C. hydrolyzes). On the other hand, at 50 ° C, it is moderately soluble: at 31 g / I in water and at 38 g / I in 20 g / I. This dissolution, unstable on cooling, is not satisfactory.
- This type of "mud” can be recycled in a new bath, according to the method described above.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- ing And Chemical Polishing (AREA)
- Detergent Compositions (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8514220 | 1985-09-19 | ||
| FR8514220A FR2587369B1 (fr) | 1985-09-19 | 1985-09-19 | Procede de decapage acide de produits en acier inoxydable |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0236354A1 EP0236354A1 (fr) | 1987-09-16 |
| EP0236354B1 true EP0236354B1 (fr) | 1989-07-12 |
Family
ID=9323241
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19860904835 Expired EP0236354B1 (fr) | 1985-09-19 | 1986-07-28 | Procede de decapage acide de produits en acier inoxydable |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0236354B1 (es) |
| JP (1) | JPS62501981A (es) |
| BR (1) | BR8606873A (es) |
| CA (1) | CA1272980A (es) |
| DE (1) | DE3664340D1 (es) |
| ES (1) | ES2000222A6 (es) |
| FI (1) | FI81126C (es) |
| FR (1) | FR2587369B1 (es) |
| MX (1) | MX168028B (es) |
| WO (1) | WO1987001739A1 (es) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5843240A (en) * | 1995-10-18 | 1998-12-01 | Novamax Itb S.R.L. | Process for stainless steel pickling and passivation without using nitric acid |
| DE19850524C2 (de) * | 1998-11-03 | 2002-04-04 | Eilenburger Elektrolyse & Umwelttechnik Gmbh | Nitratfreies Recycling-Beizverfahren für Edelstähle |
| US6554908B1 (en) | 1999-05-03 | 2003-04-29 | Henkel Kommanditgesellschaft Auf Aktien | Process for pickling stainless steel in the absence of nitric acid and in the presence of chloride ions |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5338367A (en) * | 1989-07-26 | 1994-08-16 | Ugine, Aciers De Chatillon Et Gueugnon | Pickling process in an acid bath of metallic products containing titanium or at least one chemical element of the titanium family |
| FR2650303B1 (fr) * | 1989-07-26 | 1993-12-10 | Ugine Aciers Chatillon Gueugnon | Procede de decapage en bain acide de produits metalliques contenant du titane ou au moins un element chimique de la famille du titane |
| FR2673200A1 (fr) * | 1991-02-25 | 1992-08-28 | Ugine Aciers | Procede de surdecapage de materiaux en acier tels que les aciers inoxydables et les aciers allies. |
| IT1245594B (it) * | 1991-03-29 | 1994-09-29 | Itb Srl | Processo di decapaggio e di passivazione di acciaio inossidabile senza acido nitrico |
| FR2683551B1 (fr) * | 1991-11-07 | 1994-09-16 | Ugine Sa | Procede de decapage de materiaux en acier en continu sur une ligne de traitement. |
| IT1255655B (it) * | 1992-08-06 | 1995-11-09 | Processo di decapaggio e passivazione di acciaio inossidabile senza impiego di acido nitrico | |
| IT1255855B (it) * | 1992-10-12 | 1995-11-17 | Cesare Pedrazzini | Processo di decapaggio e di passivazione per lamiere di titanio in nastro, senza impiego di acido nitrico. |
| FR2721328B1 (fr) * | 1994-06-15 | 1996-09-06 | Ugine Sa | Procédé de décapage de matériaux métalliques, notamment en acier allié, en acier inoxydable ou en alliage de titane, par une solution du type contenant des ions ferriques en milieu acide. |
| FR2745301B1 (fr) * | 1996-02-27 | 1998-04-03 | Usinor Sacilor | Procede de decapage d'une piece en acier et notamment d'une bande de tole en acier inoxydable |
| FR2772050B1 (fr) * | 1997-12-10 | 1999-12-31 | Imphy Sa | Procede de decapage d'acier et notamment d'acier inoxydable |
| GB9807286D0 (en) * | 1998-04-06 | 1998-06-03 | Solvay Interox Ltd | Pickling process |
| WO2014021639A1 (ko) * | 2012-07-31 | 2014-02-06 | 주식회사 포스코 | 오스테나이트계 스테인리스 냉연강판을 제조하기 위한 고속 산세 프로세스 |
| CN109328245A (zh) * | 2017-05-31 | 2019-02-12 | 天佑科技有限责任公司 | 为清除在不锈钢管道及构筑物焊接部位的剥落和铁锈而进行的酸洗及形成钝化膜的处理剂 |
| IT201900006672A1 (it) | 2019-05-10 | 2020-11-10 | Condoroil Stainless Srl | Unita' per il decapaggio elettrolitico interno ed esterno di tubi in acciaio inossidabile |
| KR102300834B1 (ko) | 2019-11-21 | 2021-09-13 | 주식회사 포스코 | 스테인리스강 산세용 이온성 액체 및 이를 이용한 스테인리스강의 산세방법 |
| EP3951014B1 (en) | 2020-01-09 | 2024-05-22 | Primetals Technologies Japan, Ltd. | Method for pickling steel plate and pickling apparatus |
| IT202000005848A1 (it) | 2020-03-19 | 2021-09-19 | Tenova Spa | Processo per decapare e/o passivare un acciaio inossidabile. |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2474526A (en) * | 1940-06-15 | 1949-06-28 | Monsanto Chemicals | Picking of stainless steels |
| US2564549A (en) * | 1945-07-02 | 1951-08-14 | Albert R Stargardter | Pickling treatment |
| DE899890C (de) * | 1952-03-18 | 1953-12-17 | Deutsche Edelstahlwerke Ag | Verfahren zum Regenerieren von Beizbaedern |
| JPS549120A (en) * | 1977-06-24 | 1979-01-23 | Tokai Electro Chemical Co | Method of controlling acid cleaning liquid for stainless steel |
| JPS57194262A (en) * | 1981-05-26 | 1982-11-29 | Mitsubishi Gas Chem Co Inc | Descaling method for stainless steel |
| DE3222532A1 (de) * | 1982-06-16 | 1983-12-22 | Arno 5042 Erftstadt Kuhlmann | Verfahren und mittel zum sauren beizen von austenitischen edelstaehlen |
| FR2551465B3 (fr) * | 1983-09-02 | 1985-08-23 | Gueugnon Sa Forges | Procede de decapage acide des aciers inoxydables et solution acide pour sa mise en oeuvre |
| ATE121804T1 (de) * | 1985-01-22 | 1995-05-15 | Ugine Sa | Verfahren zum säuren beizen von stahlen, insbesondere von rostfreien stahlen. |
-
1985
- 1985-09-19 FR FR8514220A patent/FR2587369B1/fr not_active Expired - Lifetime
-
1986
- 1986-07-25 CA CA000514703A patent/CA1272980A/fr not_active Expired - Lifetime
- 1986-07-28 EP EP19860904835 patent/EP0236354B1/fr not_active Expired
- 1986-07-28 JP JP50418386A patent/JPS62501981A/ja active Granted
- 1986-07-28 WO PCT/FR1986/000267 patent/WO1987001739A1/fr active IP Right Grant
- 1986-07-28 DE DE8686904835T patent/DE3664340D1/de not_active Expired
- 1986-07-28 BR BR8606873A patent/BR8606873A/pt not_active IP Right Cessation
- 1986-07-29 MX MX329086A patent/MX168028B/es unknown
- 1986-07-29 ES ES8600701A patent/ES2000222A6/es not_active Expired
-
1987
- 1987-05-18 FI FI872187A patent/FI81126C/fi not_active IP Right Cessation
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5843240A (en) * | 1995-10-18 | 1998-12-01 | Novamax Itb S.R.L. | Process for stainless steel pickling and passivation without using nitric acid |
| DE19850524C2 (de) * | 1998-11-03 | 2002-04-04 | Eilenburger Elektrolyse & Umwelttechnik Gmbh | Nitratfreies Recycling-Beizverfahren für Edelstähle |
| US6554908B1 (en) | 1999-05-03 | 2003-04-29 | Henkel Kommanditgesellschaft Auf Aktien | Process for pickling stainless steel in the absence of nitric acid and in the presence of chloride ions |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0420996B2 (es) | 1992-04-07 |
| WO1987001739A1 (fr) | 1987-03-26 |
| EP0236354A1 (fr) | 1987-09-16 |
| FI872187A (fi) | 1987-05-18 |
| MX168028B (es) | 1993-04-29 |
| ES2000222A6 (es) | 1988-01-16 |
| FR2587369A1 (fr) | 1987-03-20 |
| JPS62501981A (ja) | 1987-08-06 |
| DE3664340D1 (en) | 1989-08-17 |
| CA1272980A (fr) | 1990-08-21 |
| FI81126B (fi) | 1990-05-31 |
| FI81126C (fi) | 1990-09-10 |
| FR2587369B1 (fr) | 1993-01-29 |
| FI872187A0 (fi) | 1987-05-18 |
| BR8606873A (pt) | 1987-11-03 |
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