JP2574037B2 - How to descale stainless steel strip - Google Patents
How to descale stainless steel stripInfo
- Publication number
- JP2574037B2 JP2574037B2 JP1250509A JP25050989A JP2574037B2 JP 2574037 B2 JP2574037 B2 JP 2574037B2 JP 1250509 A JP1250509 A JP 1250509A JP 25050989 A JP25050989 A JP 25050989A JP 2574037 B2 JP2574037 B2 JP 2574037B2
- Authority
- JP
- Japan
- Prior art keywords
- steel strip
- stainless steel
- cooling
- water
- temperature
- 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 - Lifetime
Links
Landscapes
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Description
【発明の詳細な説明】 ＜産業上の利用分野＞ この発明はステンレス鋼帯の脱スケール方法に係り、
特に塩浴に続いて水洗槽に浸漬する脱スケールの前処理
における熱応力による歪の発生を抑止した脱スケール方
法に関するものである。The present invention relates to a method for descaling a stainless steel strip,
In particular, the present invention relates to a descaling method that suppresses generation of distortion due to thermal stress in a pre-treatment for descaling in which the substrate is immersed in a washing tank following a salt bath.
＜従来の技術＞ 一般に焼鈍後のステンレス鋼帯を酸洗槽に浸漬し脱ス
ケールするにあたり、前処理が行われる。すなわち、第
１図に示す如く焼鈍後のステンレス鋼帯１は、ほぼ450
℃の（NaOH＋Na2CO3の塩浴槽２に浸漬され、続いて自然
空冷後あるいは強制空冷後に水洗槽３に入り水洗すると
いう前処理を経て酸洗槽で脱スケールされる。<Prior Art> Generally, a pretreatment is performed when the annealed stainless steel strip is immersed in an pickling tank and descaled. That is, as shown in FIG. 1, the stainless steel strip 1 after annealing is almost 450
After being immersed in a salt bath 2 of (NaOH + Na 2 CO 3) at a temperature of ° C., and then subjected to natural air cooling or forced air cooling, the water enters the washing bath 3 and is washed with water.
この前処理工程におけるステンレス鋼帯１の温度変化
を第２図に示した。すなわち、塩浴を離れる点をＡ、水
洗槽３の水の入る点をＢ、水から離れる点をＣ、強制空
冷帯に入る点をＤ、強制空冷帯を出る点をＥとして表示
した。FIG. 2 shows the temperature change of the stainless steel strip 1 in this pretreatment step. That is, the point leaving the salt bath is indicated by A, the point of entering the water in the washing tank 3 is indicated by B, the point of leaving the water is indicated by C, the point of entering the forced air cooling zone is indicated by D, and the point of exiting the forced air cooling zone is indicated by E.
従来の前処理においては、塩浴槽で加熱された高温の
ステンレス鋼帯が水洗槽に浸漬した場合にセンター部と
エッヂ部の温度差は一時的に極めて増大し、この温度差
Δｔにより次式に示す熱応力σｈが発生し、これが材料
の降伏応力σｙを越えると鋼帯は形状不良を発生し、特
に厚さ0.6mm以下の薄板では冷却速度が大きいのでこの
欠陥が発生しやすく大きな問題となっていた。In the conventional pretreatment, when a high-temperature stainless steel strip heated in a salt bath is immersed in a washing tank, the temperature difference between the center part and the edge part temporarily increases extremely. When the thermal stress σ h shown below is exceeded, and this exceeds the yield stress σ y of the material, the steel strip will have a defective shape. Particularly, in the case of a thin plate having a thickness of 0.6 mm or less, the cooling rate is high, so this defect is liable to occur, and this is a major problem. Had become.
σｈ＝β・Ｅ・Δｔ これを解決する方法として塩浴槽から水洗槽までの冷
却ゾーンを長くすることや、強制空冷帯を設けることが
考えられているが、前者は脱スケールラインが長大とな
り、後者は厚さ0.3mm以下の薄板では効果が少ない。σ h = β · E · Δt To solve this problem, it is considered to lengthen the cooling zone from the salt bath to the washing bath or to provide a forced air cooling zone, but the former requires a long descaling line. On the other hand, the latter is less effective with a thin plate having a thickness of 0.3 mm or less.
そこで、さらに一層冷却効果を高めるために冷却ゾー
ンを長くしたり、強制空冷帯での冷却能力を高め、250
℃以下にすれば形状不良の発生は防止できるが、300℃
未満になるとNaOH＋Na2CO3が凝固して浸漬ロールによっ
て鋼帯に押疵を発生していた。Therefore, in order to further enhance the cooling effect, the cooling zone is lengthened, and the cooling capacity in the forced air cooling zone is increased,
If the temperature is below ℃, the occurrence of shape defects can be prevented, but 300 ℃
When the temperature was less than that, NaOH + Na 2 CO 3 was solidified and the steel strip was pressed by the immersion roll.
＜発明が解決しようとする課題＞ 本発明の目的は、厚さ0.3mm以下の薄板でも形状不良
の発生を抑え、NaOH＋Na2CO3の凝固を防止したステンレ
ス鋼帯の脱スケール方法を提案するものである。<Problem to be Solved by the Invention> An object of the present invention is to propose a descaling method for a stainless steel strip which suppresses the occurrence of shape defects even in a thin plate having a thickness of 0.3 mm or less and prevents solidification of NaOH + Na 2 CO 3. It is.
＜課題を解決するための手段＞ 本発明の要旨とするところは次の如くである。すなわ
ち、ステンレス鋼帯を塩浴槽に浸漬し続いて水洗槽で水
洗する前処理工程を有して成るステンレス鋼帯の脱スケ
ール方法において、前記塩浴槽に浸漬後のステンレス鋼
帯を、気水スプレーによる冷却または気水スプレーによ
る冷却と自然冷却との組み合わせにより250℃以下に冷
却した後、水温60℃以上の前記水洗槽で水洗することを
特徴とするステンレス鋼帯の脱スケール方法である。<Means for Solving the Problems> The gist of the present invention is as follows. That is, in a method of descaling a stainless steel strip having a pretreatment step of immersing the stainless steel strip in a salt bath and then rinsing in a washing tank, the stainless steel strip immersed in the salt bath is sprayed with air and water. A method for descaling a stainless steel strip, comprising cooling to 250 ° C. or less by cooling with water or a combination of cooling by air-water spray and natural cooling, and then rinsing with a water tub having a water temperature of 60 ° C. or more.
＜作用＞ 本発明者は、酸洗ラインの塩浴槽出側の水洗槽で発生
する形状不良について種々の検討を行った結果、250℃
以下まで冷却した後、水温が60℃以上の水洗槽で水洗す
ると、0.3mm以下の板厚でも形状不良が発生しないこと
を見い出した。<Effect> The present inventor conducted various studies on the shape defect generated in the washing tank on the exit side of the salt bath in the pickling line.
After cooling to the temperature below, it was found that when the water was washed in a water washing tank having a water temperature of 60 ° C. or more, a shape defect did not occur even with a sheet thickness of 0.3 mm or less.
しかも気水スプレーによる強制冷却などで、冷却で凝
固する塩を気中に混入する水が溶解し、凝固を防止する
ことができることを見い出した。In addition, it has been found that water mixed into the air with a salt that solidifies by cooling is dissolved by, for example, forced cooling by air-water spray, thereby preventing solidification.
本発明では塩浴槽２と水洗槽３の間に鋼帯の冷却能力
が150℃程度の気水ノズル冷却装置５を設けることが望
ましい。In the present invention, it is desirable to provide a steam-water nozzle cooling device 5 having a cooling capacity of about 150 ° C. for the steel strip between the salt bath 2 and the washing bath 3.
450℃前後の塩浴槽２を出た加熱された鋼帯１は自然
空冷され、気水ノズル冷却装置５で弱冷され、更に自然
冷却され、250℃以下の温度で水温が60℃以上の水洗槽
３に突入する。なお、この場合、気水ノズル冷却装置５
で250℃以下の温度に冷却し、水温が60℃以上の水洗槽
３に突入せしめてもよい。気水ノズルの気水比は水の粒
径が100μｍ以下になるように調整されていれば、熱伝
達係数が300Kcal/m2hr℃程度のおだやかな弱冷ができ、
100μｍ以上では急冷されるため熱応力の大きさが材料
の降伏応力を越え、形状不良が生じるので好ましくな
い。The heated steel strip 1 that has exited the salt bath 2 at about 450 ° C. is naturally cooled by air, slightly cooled by the air-water nozzle cooling device 5 and further naturally cooled, and is washed at a temperature of 250 ° C. or less and a water temperature of 60 ° C. or more. It enters the tank 3. In this case, the air-water nozzle cooling device 5
The temperature may be cooled to a temperature of 250 ° C. or less, and the water may enter the washing tank 3 having a temperature of 60 ° C. or more. If the air-water ratio of the air-water nozzle is adjusted so that the water particle size is 100 μm or less, the heat transfer coefficient can be about 300 Kcal / m 2 hr ℃, mild and gentle cooling,
If the thickness is 100 μm or more, the material is rapidly cooled and the magnitude of the thermal stress exceeds the yield stress of the material.
次に水洗槽３の水温について説明する。水温は高いほ
ど水冷による熱伝達係数は小さく、鋼帯幅方向の温度差
が生じないので熱応力の発生が少ないため、水温を60℃
以上に限定した。Next, the water temperature of the washing tank 3 will be described. The higher the water temperature, the smaller the heat transfer coefficient due to water cooling, and there is no temperature difference in the width direction of the steel strip.
Limited to the above.
本発明における代表的鋼帯表面温度の変化を第２図に
示した。A,B,C,D,Eは第１図の測定点を示す。FIG. 2 shows changes in the surface temperature of a typical steel strip in the present invention. A, B, C, D, and E indicate the measurement points in FIG.
＜実施例＞ 板厚0.28mmのステンレス鋼帯を450℃のNaOHとNa2CO3
の混合塩浴槽に浸漬し、続いて、気水比3m3/3，水の
粒径100μｍ以下の気水スプレーにて156℃に冷却した
後、148℃で水温70℃の水洗槽で冷却した。その結果、
ステンレス鋼帯には熱歪による形状不良の発生及び押疵
等の欠陥の発生はみられなかった。<Example> A stainless steel strip having a plate thickness of 0.28 mm was subjected to NaOH and Na 2 CO 3 at 450 ° C.
Mixed salt was immersed in a bath, followed by the gas-water ratio 3m 3/3, after cooling to 156 ° C. with water having a particle size of 100μm or less of water-air spray, and cooled in the washing bath at a water temperature 70 ° C. at 148 ° C. . as a result,
The stainless steel strip did not show any shape defects due to thermal strain and no defects such as dents.
＜発明の効果＞ 本発明によれば、鋼帯を気水スプレーで冷却するの
で、冷却時における鋼帯内の温度のバラツキが減少し、
熱応力の発生を防止することができ、かつ附着した塩類
を溶解除去できるので形状不良の発生及び押疵の発生が
防止できる。<Effects of the Invention> According to the present invention, since the steel strip is cooled by air-water spray, the temperature variation in the steel strip during cooling is reduced,
The occurrence of thermal stress can be prevented, and the attached salts can be dissolved and removed, so that the occurrence of shape defects and the occurrence of dents can be prevented.
第１図は本発明が用いられる塩浴前処理装置を示す断面
図、第２図は本発明実施例および従来例の鋼帯の水洗槽
浸漬前後の温度変化を示す線図である。 １……ステンレス鋼帯、２……塩浴槽、 ３……水洗槽、４……浸漬ロール、 ５……気水ノズル冷却装置。FIG. 1 is a sectional view showing a salt bath pretreatment apparatus to which the present invention is applied, and FIG. 2 is a diagram showing temperature changes before and after immersion of a steel strip according to an embodiment of the present invention and a conventional steel strip. 1 ... Stainless steel strip, 2 ... Salt bath, 3 ... Washing tank, 4 ... Immersion roll, 5 ... Air / water nozzle cooling device.
Claims (1)
洗槽で水洗する前処理工程を有して成るステンレス鋼帯
の脱スケール方法において、前記塩浴槽に浸漬後のステ
ンレス鋼帯を、気水スプレーによる冷却または気水スプ
レーによる冷却と自然冷却との組み合わせにより250℃
以下に冷却した後、水温60℃以上の前記水洗槽で水洗す
ることを特徴とするステンレス鋼帯の脱スケール方法。1. A method for descaling a stainless steel strip comprising a pretreatment step of immersing the stainless steel strip in a salt tub and subsequently rinsing the stainless steel strip in a washing tub, wherein the stainless steel strip immersed in the salt tub is 250 ° C by cooling with air-water spray or a combination of cooling with air-water spray and natural cooling
A descaling method for a stainless steel strip, comprising: cooling the steel sheet to a temperature below 60 ° C .;
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1250509A JP2574037B2 (en) | 1989-09-28 | 1989-09-28 | How to descale stainless steel strip |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1250509A JP2574037B2 (en) | 1989-09-28 | 1989-09-28 | How to descale stainless steel strip |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03115591A JPH03115591A (en) | 1991-05-16 |
| JP2574037B2 true JP2574037B2 (en) | 1997-01-22 |
Family
ID=17208948
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1250509A Expired - Lifetime JP2574037B2 (en) | 1989-09-28 | 1989-09-28 | How to descale stainless steel strip |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2574037B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6442588A (en) * | 1987-08-07 | 1989-02-14 | Kawasaki Steel Co | Method for descaling stainless steel strip |
-
1989
- 1989-09-28 JP JP1250509A patent/JP2574037B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03115591A (en) | 1991-05-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2541901A (en) | Pickling of aluminum | |
| JP2574037B2 (en) | How to descale stainless steel strip | |
| JPS5741821A (en) | Descaling method for steel strip | |
| CA1060322A (en) | Method and apparatus for water quenching steel strip with reduced amount of oxidation | |
| JPS609834A (en) | Method and device for cooling steel strip | |
| JPH0118974B2 (en) | ||
| JPH04182020A (en) | Method for descaling stainless steel sheet | |
| KR20210036539A (en) | Composition for enhancing surface property of aluminium sheet and method of enhancing using the same | |
| JP3319067B2 (en) | Manufacturing method of steel wire rod | |
| JP2960196B2 (en) | Continuous pickling of steel strip | |
| JP2734356B2 (en) | Method for reducing internal stress of metal sheet for electronic equipment | |
| JPH10265986A (en) | Method for continuously annealing and pickling cold rolled stainless steel strip and device therefor | |
| JPH04293792A (en) | Descaling method of stainless steel strip | |
| JPS6286182A (en) | Treatment of grain oriented electrical steel strip | |
| JPH04323391A (en) | Method for controlling descaling of steel strip | |
| JP2968358B2 (en) | Fast descaling method for steel strip | |
| JPH08176866A (en) | Method for descaling stainless steel strip | |
| JPH0987871A (en) | Steel strip cooler for pretreatment before descaling of stainless steel strip and pretreatment before descaling of stainless steel strip | |
| JPH05320961A (en) | Method for descaling stainless hot rolled steel sheet | |
| JPH04129507U (en) | Steel strip descaling equipment | |
| JPH01266912A (en) | Method for rolling stainless steel | |
| JPH1147819A (en) | Peeled scale removing device | |
| JPS5864322A (en) | Method and device for cooling of band-like steel plate | |
| JPH0770776A (en) | Descaling method for steel wire | |
| JP2635464B2 (en) | Manufacturing method of controlled cooling steel sheet |