SE439025B - SET TO REMOVE OXID LAYERS FROM THE SURFACE OF HOT ROLLED STAINLESS STEEL - Google Patents
SET TO REMOVE OXID LAYERS FROM THE SURFACE OF HOT ROLLED STAINLESS STEELInfo
- Publication number
- SE439025B SE439025B SE7907610A SE7907610A SE439025B SE 439025 B SE439025 B SE 439025B SE 7907610 A SE7907610 A SE 7907610A SE 7907610 A SE7907610 A SE 7907610A SE 439025 B SE439025 B SE 439025B
- Authority
- SE
- Sweden
- Prior art keywords
- solution
- stainless steel
- sulfuric acid
- remove
- rolled stainless
- Prior art date
Links
- 229910001220 stainless steel Inorganic materials 0.000 title claims description 11
- 239000010935 stainless steel Substances 0.000 title claims description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 11
- 235000016068 Berberis vulgaris Nutrition 0.000 claims description 7
- 241000335053 Beta vulgaris Species 0.000 claims description 7
- 238000005096 rolling process Methods 0.000 claims description 2
- 238000009210 therapy by ultrasound Methods 0.000 claims description 2
- 238000001816 cooling Methods 0.000 claims 1
- 238000005554 pickling Methods 0.000 description 8
- 239000000203 mixture Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 235000011149 sulphuric acid Nutrition 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000009533 lab test Methods 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
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000010327 methods by industry Methods 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- GQPLMRYTRLFLPF-UHFFFAOYSA-N nitrous oxide Inorganic materials [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002110 toxicologic effect Effects 0.000 description 1
- 231100000027 toxicology Toxicity 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
- C23G1/081—Iron or steel solutions containing H2SO4
Description
19o7s1o-s 2 en kombination mellan betning i H/HNO5 och H01) eller b) bet- ning i HCl, àtföljt eventuellt av betning i H/HNO5, betning i reducerande eller oxiderande saltbad samt slutligen betning i H01. 19o7s1o-s 2 a combination between pickling in H / HNO5 and H01) or b) pickling in HCl, followed possibly by pickling in H / HNO5, pickling in reducing or oxidizing salt baths and finally pickling in H01.
Föreliggande uppfinning har till ändamål att åstadkom- ma ett sätt att avlägsna oxiden eller glödskalet från den di- rektkylda valsprodukten, såsom valstråden, av rostfritt stål med hjälp av en enklare, miljövänligare och billigare kemisk behandling.The object of the present invention is to provide a method of removing the oxide or scale from the directly cooled roll product, such as the wire rod, of stainless steel by means of a simpler, more environmentally friendly and cheaper chemical treatment.
Vid sättet enligt uppfinningen har konstaterats den överraskande effekten att glödskalet eller oxidskiktet på den varmvalsade produkten av rostfritt stål kan-avlägsnas genom behandling under en tidrymd av 1 - 120 minuter i en lösning av utspädd svavelsyra med en koncentration av 25 - 1200 g sva- velsyra per liter lösning, varvid temperaturen hos lösningen hållas via ao - 1oo° o.In the method according to the invention, the surprising effect has been found that the scale or oxide layer on the hot-rolled stainless steel product can be removed by treatment for a period of 1 - 120 minutes in a solution of dilute sulfuric acid with a concentration of 25 - 1200 g sulfuric acid. per liter of solution, the temperature of the solution being maintained via ao - 100 ° o.
Vid en speciell utföringsform enligt uppfinningen hål- les svavelsyrakoncentrationen vid 200 - 400 g per liter bet- lösning. Vidare hålles vid en speciell utföringsform av upp- finningen temperaturen hos betlösningen vid 65 - 85° C. Den varmvalsade produkten av rostfritt stål behandlas vid en spe- ciell utföringsform av uppfinningen under en tidrymd av 10 - 20 minuter.In a special embodiment according to the invention, the sulfuric acid concentration is maintained at 200 - 400 g per liter of beet solution. Furthermore, in a special embodiment of the invention, the temperature of the beet solution is maintained at 65 - 85 ° C. The hot-rolled stainless steel product is treated in a special embodiment of the invention for a period of 10 to 20 minutes.
Sättet att avlägsna oxidskikt på valsprodukter i en- lighet med uppfinningen eliminerar helt de problem med nitrösa gaser som uppstår vid betning med H/HNO5, varjämte omhänder- tagandet av det förbrukade betbadet avsevärt förenklas.The method of removing oxide layers on roll products in accordance with the invention completely eliminates the problems with nitrous gases which arise during pickling with H / HNO5, as well as the disposal of the spent pickling bath is considerably simplified.
Förutom de miljömässiga fördelar som vinnes medelst sättet enligt uppfinningen genom att de toxikologiska risker- na minskar vinnes ur processteknisk synpunkt bl.a. den förde- len att hanteringen av betbadet blir enklare genom enklare analys och dosering av tillsatser, varjämte omhändertagandet av avlägsnat glödskal blir enklare och bättre. Uppfinningen ger även mycket stora ekonomiska fördelar genom att svavelsy- ran är den billigaste mineralsyran samt omhändertagandet och utvinningen av metaller såsom järn, krom och nickel fràn det förbrukade betbadet förenklas, varjämte reningen av gaserna (svavelsyradimma) avsevärt förenklas. Sättet enligt uppfin- 5 7907610-s ningen beskrives närmare i det följande under hänvisning till nedanstående utföringsexempel på uppfinningen jämte ett jämfö- rande exempel som faller utanför ramen för uppfinningen.In addition to the environmental benefits that are gained by the method according to the invention by reducing the toxicological risks, from a process engineering point of view, e.g. the advantage that the handling of the beet bath is simpler through simpler analysis and dosing of additives, and the disposal of removed embers is simpler and better. The invention also offers very great economic advantages in that sulfuric acid is the cheapest mineral acid and the disposal and recovery of metals such as iron, chromium and nickel from the spent beet bath is simplified, and the purification of the gases (sulfuric acid mist) is considerably simplified. The method according to the invention is described in more detail in the following with reference to the following exemplary embodiments of the invention together with a comparative example which falls outside the scope of the invention.
Uppfinningen bygger på det faktum att cxidsammansätt- ningen på direktkyld valsprodukt, såsom valstràd, skiljer sig såväl med avseende på metalloxidinnehåll som skikttjocklek från oxidsammansättningen hos den konventionellt värmebehand- lade tråden och av den anledningen kan borttagas med svavelsy- ra.The invention is based on the fact that the oxide composition of directly cooled roll product, such as wire rod, differs both in terms of metal oxide content and layer thickness from the oxide composition of the conventional heat-treated wire and for that reason can be removed with sulfuric acid.
Vid utförda laboratorieförsök att avlägsna glödskalet hos direktkyld valstråd av rostfritt stål av typ SIS 2532 be- handlades tråden i en 2M H2SO4-lösning vid en temperatur av 85° C under 10 minuter. Under denna behandling kunde man kons- tatera en kraftig reaktion i lösningen, varvid gasutveckling uppstod. Den gas som därvid erhölls var vätgas. När valstrn- den togs upp ur HZSO4-lösningen kunde man visuellt iakttaga en attack på oxidskiktet och att en nyansförändring hade in- träffat. Vid efterföljande högtrycksspolning med vatten in- träffade det helt oväntade resultatet att valstråden blev helt befriad från oxidskiktet och en metalliskt ren yta erhölls.In laboratory experiments to remove the scale of directly cooled SIS 2532 stainless steel wire rod, the wire was treated in a 2M H 2 SO 4 solution at a temperature of 85 ° C for 10 minutes. During this treatment, a strong reaction in the solution could be observed, whereby gas evolution occurred. The gas thus obtained was hydrogen. When the rolling stock was taken up from the HZSO4 solution, one could visually observe an attack on the oxide layer and that a shade change had occurred. Upon subsequent high-pressure rinsing with water, the completely unexpected result occurred that the wire rod was completely freed from the oxide layer and a metallically clean surface was obtained.
Oxidskiktet som till 90 % fanns kvar på valstràdytan efter H2S04-behandlingen kunde avlägsnas antingen med högtrycksspol- ning eller med ultraljudbehandling i vatten. Slammet som sam- lades på behandlingskärlets botten kunde separeras efter nå- gon timme och var därigenom lätt att avskilja exempelvis ge- nom dekantering. Ett antal ytterligare försök har utförts med olika HQSO4-koncentraticner på olika kvaliteter av rost- fritt stàl av direktkyld valstràd med samma goda resultat som ovan. Två exempel på dylika försök ges nedan jämte såsom jäm- förelse exempel på ett sätt som inte faller under uppfinning- ens ram.The oxide layer, which remained at 90% on the wire rod surface after the H2SO4 treatment, could be removed either by high-pressure rinsing or by ultrasonic treatment in water. The sludge collected on the bottom of the treatment vessel could be separated after an hour and was thus easy to separate, for example by decantation. A number of further experiments have been performed with different HQSO4 concentrates on different grades of stainless steel of direct-cooled wire rod with the same good results as above. Two examples of such experiments are given below, as well as comparative examples of a method which does not fall within the scope of the invention.
Exempel l I en 150 ml glasbägare bereddes 100 ml av en SM H2S04- blandning. Blandningen värmdes till 750 C och en mångfald bi- tar av direktkyld valstràd av rostfritt stål betades i 15 min.Example 1 In a 150 ml glass beaker, 100 ml of a SM H 2 SO 4 mixture was prepared. The mixture was heated to 750 DEG C. and a variety of pieces of directly cooled stainless steel wire rod were pickled for 15 minutes.
Trádkvaliteterna var SIS 2520, 2552, 2540, 2545 och AISI 508L.The wire grades were SIS 2520, 2552, 2540, 2545 and AISI 508L.
Vid en efterföljande högtrycksspolning med vatten blev tràdbitarna fria från oxid (glödskal). 79057610-5 4 Exempel 2 I en 150 ml glasbägare bereddes 100 ml av en 5M HESOQ- blandning. Blandningen värmdes till 750 O och en mångfald bi- tar av glödgad valstråd av rostfritt stål betades mellan 15 till 120 min. Trådkvaliteterna var SIS 2520, 2552, 2540, 2545 och AISI 508L. 5 Vid efterföljande högtrycksspolning med vatten kunde man konstatera att 90 % av oxiden blev kvar på valstrådsytan.During a subsequent high-pressure rinsing with water, the wire pieces became free of oxide (shell). Example 2 In a 150 ml glass beaker, 100 ml of a 5M HESOQ mixture was prepared. The mixture was heated to 750 DEG C. and a variety of pieces of annealed stainless steel wire was pickled between 15 to 120 minutes. The wire grades were SIS 2520, 2552, 2540, 2545 and AISI 508L. Subsequent high-pressure rinsing with water showed that 90% of the oxide remained on the wire rod surface.
Exempel 5 I ett bad med koncentrationen 5M HESOQ och volymen 5000 l och temperaturen 75° C behandlades 4 st trådringar å 500 kg/ring av direktkyld valstràd av rostfritt stål av dimen- sionen 5,60 till 8,0 mm ø. Trådkvaliteterna var SIS 2520, SIS 2552, SIS 2540, SIS 2545 och AISI 508L.Example 5 In a bath with a concentration of 5M HESOQ and a volume of 5000 l and a temperature of 75 ° C, 4 wire rings of 500 kg / ring of directly cooled stainless steel wire rod of the dimension 5.60 to 8.0 mm ø were treated. The wire grades were SIS 2520, SIS 2552, SIS 2540, SIS 2545 and AISI 508L.
Efter behandling under 15 min i betbadet och en efter- följande högtrycksspolning med vatten var trådringarna fria från oxid. Totalt har 200 ton av ovanstående kvaliteter i di- rektkylt utförande behandlats med mycket gott resultat.After treatment for 15 minutes in the beet bath and a subsequent high-pressure rinsing with water, the wire rings were free of oxide. A total of 200 tonnes of the above grades in directly cooled design have been treated with very good results.
För att undersöka om den erhållna effekten var selek- tiv för svavelsyra utfördes ett flertal försök med olika kom- binationer av mineralsyror såsom salt-, salpeter- och fosfor- syra. Inte vid någon av de försökskombinationer som utfördes uppnâddes samma goda resultat som med enbart HZSO4.To investigate whether the effect obtained was selective for sulfuric acid, several experiments were performed with different combinations of mineral acids such as hydrochloric, nitric and phosphoric acid. None of the experimental combinations performed achieved the same good results as with HZSO4 alone.
Ett flertal försök att med H2SO4 avlägsna oxiden från olika rostfria stål som glödgats har utförts men betningsre- sultaten har blivit dåliga. Vanligtvis har ca 90 % av oxiden blivit kvar.Several attempts to remove the oxide from various annealed stainless steels with H2SO4 have been carried out, but the pickling results have been poor. Usually about 90% of the oxide has remained.
De praktiska försök som hittills utförts under drifts- mässiga förhållanden har givit goda belägg för att tekniska möjligheter finns för att under produktionsmässiga förhållan- den använda sättet enligt föreliggande uppfinning.The practical experiments which have hitherto been carried out under operational conditions have provided good evidence that there are technical possibilities for using the method according to the present invention under production conditions.
Claims (3)
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7907610A SE439025B (en) | 1979-09-13 | 1979-09-13 | SET TO REMOVE OXID LAYERS FROM THE SURFACE OF HOT ROLLED STAINLESS STEEL |
| DE19803029525 DE3029525A1 (en) | 1979-09-13 | 1980-08-04 | METHOD FOR REMOVING OXIDE LAYERS FROM THE SURFACE OF HOT ROLLED, STAINLESS STEEL |
| GB8026245A GB2058140B (en) | 1979-09-13 | 1980-08-12 | Removing oxide scale from surface of stainless steel |
| ES494393A ES494393A0 (en) | 1979-09-13 | 1980-08-20 | METHOD OF REMOVING HOT ROLLED STAINLESS STEEL SURFACE OXIDE SCREW |
| NL8004889A NL8004889A (en) | 1979-09-13 | 1980-08-29 | METHOD FOR REMOVING THE OXIDE SKIN OF STAINLESS STEEL. |
| JP12072980A JPS5641012A (en) | 1979-09-13 | 1980-09-02 | Method of removing oxide scale from surface of stainless steel hot rolled |
| IT24478/80A IT1132666B (en) | 1979-09-13 | 1980-09-05 | METHOD TO ELIMINATE OXIDE FLAKES FROM THE SURFACE OF HOT ROLLED STAINLESS STEELS |
| FR8019698A FR2465012A1 (en) | 1979-09-13 | 1980-09-12 | PROCESS FOR REMOVING OXIDE LAYERS FROM THE STEEL SURFACE |
| BE0/202093A BE885220A (en) | 1979-09-13 | 1980-09-12 | PROCESS FOR REMOVING OXIDIZED LAYERS FROM THE STEEL SURFACE |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7907610A SE439025B (en) | 1979-09-13 | 1979-09-13 | SET TO REMOVE OXID LAYERS FROM THE SURFACE OF HOT ROLLED STAINLESS STEEL |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| SE7907610L SE7907610L (en) | 1981-03-14 |
| SE439025B true SE439025B (en) | 1985-05-28 |
Family
ID=20338819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SE7907610A SE439025B (en) | 1979-09-13 | 1979-09-13 | SET TO REMOVE OXID LAYERS FROM THE SURFACE OF HOT ROLLED STAINLESS STEEL |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5641012A (en) |
| BE (1) | BE885220A (en) |
| DE (1) | DE3029525A1 (en) |
| ES (1) | ES494393A0 (en) |
| FR (1) | FR2465012A1 (en) |
| GB (1) | GB2058140B (en) |
| IT (1) | IT1132666B (en) |
| NL (1) | NL8004889A (en) |
| SE (1) | SE439025B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NO175906C (en) * | 1992-05-18 | 1995-01-04 | Leif Inge Aanestad | Method of metal coating interior surfaces of tanks and pipes |
| TW416996B (en) * | 1996-05-24 | 2001-01-01 | Armco Inc | Hydrogen peroxide pickling of stainless steel |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB385429A (en) * | 1931-12-31 | 1932-12-29 | Wiggin & Co Ltd Henry | Improvements relating to the treatment of corrosion or heat-resisting alloys to remove oxide scale therefrom |
| US2605775A (en) * | 1947-02-21 | 1952-08-05 | Superior Steel Corp | Process of teating cold rolled straight chrome type stainless steel |
| US2895856A (en) * | 1955-12-15 | 1959-07-21 | United States Steel Corp | Method of pickling chromium-containing steel tubes |
| US2981643A (en) * | 1958-02-19 | 1961-04-25 | Russell D Baybarz | Process for descaling and decontaminating metals |
-
1979
- 1979-09-13 SE SE7907610A patent/SE439025B/en not_active IP Right Cessation
-
1980
- 1980-08-04 DE DE19803029525 patent/DE3029525A1/en not_active Withdrawn
- 1980-08-12 GB GB8026245A patent/GB2058140B/en not_active Expired
- 1980-08-20 ES ES494393A patent/ES494393A0/en active Granted
- 1980-08-29 NL NL8004889A patent/NL8004889A/en not_active Application Discontinuation
- 1980-09-02 JP JP12072980A patent/JPS5641012A/en active Pending
- 1980-09-05 IT IT24478/80A patent/IT1132666B/en active
- 1980-09-12 BE BE0/202093A patent/BE885220A/en not_active IP Right Cessation
- 1980-09-12 FR FR8019698A patent/FR2465012A1/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| GB2058140A (en) | 1981-04-08 |
| JPS5641012A (en) | 1981-04-17 |
| ES8202065A1 (en) | 1982-02-01 |
| FR2465012A1 (en) | 1981-03-20 |
| SE7907610L (en) | 1981-03-14 |
| IT8024478A0 (en) | 1980-09-05 |
| DE3029525A1 (en) | 1981-04-02 |
| GB2058140B (en) | 1982-12-22 |
| IT1132666B (en) | 1986-07-02 |
| BE885220A (en) | 1981-03-12 |
| ES494393A0 (en) | 1982-02-01 |
| NL8004889A (en) | 1981-03-17 |
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| Date | Code | Title | Description |
|---|---|---|---|
| NUG | Patent has lapsed |
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