JPH04165090A - Method and device for descaling stainless steel - Google Patents
Method and device for descaling stainless steelInfo
- Publication number
- JPH04165090A JPH04165090A JP28829390A JP28829390A JPH04165090A JP H04165090 A JPH04165090 A JP H04165090A JP 28829390 A JP28829390 A JP 28829390A JP 28829390 A JP28829390 A JP 28829390A JP H04165090 A JPH04165090 A JP H04165090A
- Authority
- JP
- Japan
- Prior art keywords
- treated
- molten salt
- washing tank
- descaling
- stainless steel
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 41
- 229910001220 stainless steel Inorganic materials 0.000 title claims description 27
- 239000010935 stainless steel Substances 0.000 title claims description 27
- 150000003839 salts Chemical class 0.000 claims abstract description 90
- 239000000463 material Substances 0.000 claims abstract description 65
- 238000005406 washing Methods 0.000 claims abstract description 34
- 239000007921 spray Substances 0.000 claims abstract description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 23
- 238000000137 annealing Methods 0.000 claims abstract description 19
- 238000005507 spraying Methods 0.000 claims abstract description 5
- 159000000011 group IA salts Chemical class 0.000 claims abstract 2
- 239000007864 aqueous solution Substances 0.000 claims description 13
- 238000011282 treatment Methods 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 18
- 229910000831 Steel Inorganic materials 0.000 abstract description 16
- 239000010959 steel Substances 0.000 abstract description 16
- 239000003513 alkali Substances 0.000 abstract description 4
- 238000010791 quenching Methods 0.000 abstract description 2
- 230000000171 quenching effect Effects 0.000 abstract description 2
- 238000010438 heat treatment Methods 0.000 description 13
- 239000000243 solution Substances 0.000 description 6
- 235000011121 sodium hydroxide Nutrition 0.000 description 5
- 150000001447 alkali salts Chemical class 0.000 description 4
- 238000007654 immersion Methods 0.000 description 4
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 238000005554 pickling Methods 0.000 description 3
- 238000004881 precipitation hardening Methods 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- KEAYESYHFKHZAL-UHFFFAOYSA-N Sodium Chemical compound [Na] KEAYESYHFKHZAL-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910000734 martensite Inorganic materials 0.000 description 2
- 150000007522 mineralic acids Chemical class 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 239000012312 sodium hydride Substances 0.000 description 2
- 229910000104 sodium hydride Inorganic materials 0.000 description 2
- 235000010344 sodium nitrate Nutrition 0.000 description 2
- 239000004317 sodium nitrate Substances 0.000 description 2
- 239000002436 steel type Substances 0.000 description 2
- 239000010965 430 stainless steel Substances 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 150000004678 hydrides Chemical class 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000002075 main ingredient Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 235000011118 potassium hydroxide Nutrition 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- -1 steam Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
- 238000005491 wire drawing Methods 0.000 description 1
Landscapes
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
Description
【発明の詳細な説明】
【産業上の利用分野〕
本発明はステンレス鋼の焼鈍などのための加熱後の脱ス
ケール処理法と装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for descaling treatment after heating for annealing stainless steel.
より具体的には、クローム含有鋼、特に１８クロームス
テンレス鋼、１８クローム・８ニツケルステンレス鋼を
基本とし、それらに更に各種の改良元素を添加した各種
ステンレス鋼の帯材、板材の焼鈍などの加熱の後の脱ス
ケール処理に関し、それらの材料を圧延、線引後、固溶
化焼鈍やその他の熱処理のために加熱したことにより生
ずる酸化皮膜を溶融ソルトを使用して除去するに際し、
従来のようにソルトバス中を通過させる代りに、焼鈍炉
を出て移送される鋼材を進行方向に対し斜下向きに傾斜
させて走行させる間に、アルカリ溶融塩をノズルから噴
射し処理した後水洗槽に導くことにより、ソルトバス法
では被処理材料をソルトバスの浴面下の前後に配置され
たロールを通過させて案内するため、被処理材料とロー
ルとの接触により発生が不可避であったスクラッチキズ
及び押し傷などを回避し得る処理方法と装置に関する。More specifically, the heating process includes annealing of various stainless steel strips and plates based on chromium-containing steel, especially 18 chrome stainless steel, 18 chrome/8 nickel stainless steel, and various improving elements added thereto. Regarding descaling treatment after rolling, wire drawing, and heating for solution annealing and other heat treatments, oxide films are removed using molten salt.
Instead of passing through a salt bath as in the conventional method, the steel material leaving the annealing furnace is run at an angle downward relative to the direction of travel, while alkaline molten salt is injected from a nozzle to treat the steel material, followed by washing with water. In the salt bath method, the material to be treated is guided through rolls placed before and after the bath surface of the salt bath. The present invention relates to a processing method and device that can avoid scratches, pressure marks, etc.
［従来の技術］
ステンレス鋼の帯材、線材が建築物、車両、家庭電器、
事務用機器などに多用されるようになったのにに伴い、
それらの鋼材をユーザーの要求する種々の寸法に仕上げ
るための圧延、線引も多岐化し、それに伴う焼鈍も不可
欠となるが、焼鈍によって生じた酸化皮膜を除去する処
理も一貫した連続方式で行う必要がある。[Prior art] Stainless steel strips and wires are used in buildings, vehicles, home appliances,
As it has come to be widely used in office equipment, etc.
The rolling and drawing methods used to finish these steel materials into the various dimensions requested by users are becoming more diverse, and the accompanying annealing is also essential, but the process to remove the oxide film produced by annealing also needs to be carried out in a consistent and continuous manner. There is.
前述した酸化皮膜は、スケールと呼ばれ、以下本明細書
でもスケールと呼ぶが、この種のスケールの除去には、
大別すると、
（１）無機強酸または中性塩を用いる電解方式と、（２
）溶融アルカリ塩中に浸漬するソルトバス方式のいずれ
かにより行われていた。The oxide film mentioned above is called scale, and will be referred to hereinafter as scale, but to remove this type of scale,
Broadly speaking, there are (1) electrolytic methods using strong inorganic acids or neutral salts, and (2)
) It was carried out by either the salt bath method of immersion in molten alkali salt.
上記の２種の処理法の中でも、（２）のソルトバス方式
は、溶融塩、いわゆるソルトがスケールのみに選択的に
作用して母材金属であるステンレス鋼には作用しないこ
と、温度調節が容易であり処理時間が短く脱スケールが
完全で、しかも良好な仕上がり面が得られるなどの点か
ら現在でも多用されている。Among the above two treatment methods, the salt bath method (2) is characterized by the fact that the molten salt, so-called salt, acts selectively only on the scale and does not act on the base metal, stainless steel. It is still widely used today because it is easy, takes a short processing time, completely descales, and provides a good finished surface.
従来のソルトバス方式は、苛性ソーダｌＮａ０旧を主剤
として、４００〜５００℃に保持した混合アルカリ溶融
塩浴中に浸漬するものであって、さらに脱スケール効果
を高めるために、他の添加剤を配合するようになったが
、添加剤の種類によりＳｏｄｉｕｍＨｙｄｒｉｄｅ法と
Ｈｏｏｋｅｒ法に大別される。The conventional salt bath method uses caustic soda lNaO as the main ingredient and is immersed in a mixed alkali molten salt bath maintained at 400 to 500°C, and other additives are added to further enhance the descaling effect. However, it is broadly divided into the Sodium Hydride method and the Hooker method depending on the type of additive.
１１Ｓｏｄｉｕｉ Ｈｙｄｒｉｄｅ法
苛性ソーダ（ＮａＯ旧に、還元剤として１．５〜２％
′の水化ソーダ（ＮａＨｌを添加しながら３７０℃程度
のソルトバス中に浸漬すると、次に示す反応式２式％
により、ステンレス鋼表面に生じたスケール成分として
のＦｅＯ・Ｃｒ２ｅｓを、酸に可溶なＦｅとＣｒＯに変
化させ、次に水洗し、酸中に浸漬することにより脱スケ
ールする。11 Sodiui Hydride method Caustic soda (formerly NaO, 1.5-2% as a reducing agent)
When immersed in a salt bath at about 370℃ while adding sodium hydride (NaHl), FeO・Cr2es as a scale component formed on the stainless steel surface can be converted into acid according to the following reaction formula 2. It is converted into soluble Fe and CrO, then washed with water and descaled by immersion in acid.
２１Ｈｏｏｋｅｒ法
苛性ソーダに５〜４０％の硝酸ソーダ（ＮａＮＯｘｌ
を酸化剤として添加し、４００〜５００℃に保持したソ
ルトバス中に浸漬し、次に示す反応式
２式％
によりスケール成分を可溶性の塩として溶出させ後続す
る酸洗により脱スケールする。21Hooker method Add 5 to 40% sodium nitrate (NaNOxl) to caustic soda.
is added as an oxidizing agent and immersed in a salt bath maintained at 400 to 500°C, scale components are eluted as soluble salts according to the following reaction formula 2, and descaled by subsequent pickling.
上記１）と２）の２法を改良した方法も開示されている
が、いずれもソルトバス中に浸漬させるという点で軌を
−にしている。Methods that are improved from the above two methods 1) and 2) have also been disclosed, but both are different from each other in that they involve immersion in a salt bath.
前述したＨｏｏｋｅｒ法によるソルトバス方式は、溶融
塩を保持した槽中に被処理ステンレス鋼材を浸漬させる
必要上、帯鋼■をロール状のまま連続移送してソルトバ
ス２４中に浸漬させるためには、第２図に示すようにソ
ルトバスの槽２４の入口側と出口側で、ソルトバスの浴
面下に配置した一対のテンションロール２６を通過させ
、さらに絞りロール２７、洗滌設備２８、酸洗設備２９
などを通過させる必要がある。In the salt bath method using the Hooker method described above, since it is necessary to immerse the stainless steel material to be treated in a tank holding molten salt, it is necessary to continuously transport the steel strip in the form of a roll and immerse it in the salt bath 24. As shown in FIG. 2, a pair of tension rolls 26 placed below the bath surface of the salt bath are passed through at the inlet and outlet sides of the salt bath tank 24, and a squeezing roll 27, washing equipment 28, and pickling rollers are passed through. Equipment 29
etc. need to be passed.
これらのテンションロール２６は、高温に保持されてい
るソルトバス２４中に配置されるため、耐食性と耐熱性
を必要とし、しかも高温浴中で被処理材と連続接触して
いるため表面に酸化被膜やキズが発生し、完全に平滑な
表面を保つことは不可能なことにより、接触の相手とな
るステンレス鋼に対して引掻きによるスクラッチキズや
押し傷などを発生させるという問題があった。These tension rolls 26 are placed in the salt bath 24 which is maintained at a high temperature, so they require corrosion resistance and heat resistance.Moreover, since they are in continuous contact with the material to be treated in the high temperature bath, an oxide film is formed on the surface. Since it is impossible to maintain a completely smooth surface, there is a problem in that scratches and press marks occur on the stainless steel with which it comes into contact.
ステンレス鋼の帯材なとでは、最近での用途が建築物や
車輛などの内部または外部での表面の装飾的目的に供さ
れることが多くなったため、スクラッチキズの発生は重
大な品質欠陥とされるようになった。Recently, stainless steel strips have been increasingly used for decorative purposes on the interior or exterior of buildings, vehicles, etc., so scratches are considered a serious quality defect. It started to be done.
（３）ソルトバス しない スケール２１）スルト
バス浸漬によらず脱スケールを行う方法として提案され
たのが、特公昭５２−４３７６６号公報に開示された脱
スケール法である。(3) No salt bath Scaling 21) A descaling method disclosed in Japanese Patent Publication No. 43766/1983 was proposed as a method for descaling without immersion in a salt bath.
この方法は、前述のソルトバス法で脱スケール剤として
用いた苛性ソーダ、苛性カリ等のアルカリを水に溶解さ
せて水溶液とし、ステンレス鋼などの表面を濡らし、大
気中或いは酸素を含む雰囲気中で所定の時間加熱するこ
とにより、鋼材表面に適用したアルカリ水溶液皮膜中の
水分を、高温の被処理材表面で蒸発させ、アルカリ溶融
塩皮膜に変化させ、次に大気中や酸素含有雰囲気中の酸
素を利用し、１ｏｏｋｅｒでの硝酸ソーダに相当する酸
化反応により、従来のソルトバス使用に相当する脱スケ
ールを行うものである。In this method, an alkali such as caustic soda or caustic potash used as a descaling agent in the salt bath method described above is dissolved in water to form an aqueous solution, wet the surface of stainless steel, etc., and then apply the solution to a specified level in the air or an atmosphere containing oxygen. By heating for a period of time, the water in the alkaline aqueous solution coating applied to the steel surface is evaporated on the high-temperature surface of the treated material, changing to an alkaline molten salt coating, and then oxygen in the air or oxygen-containing atmosphere is utilized. However, an oxidation reaction equivalent to sodium nitrate in one ooker is used to perform descaling equivalent to the use of a conventional salt bath.
この方法により、ソルトバスの設置を必要とすることな
（、スプレー、塗布などにより被処理材の表面を濡らす
だけでよいので、設備コスト、溶液の濃度調節、スクラ
ッチキズの防止に有効であるとされている。This method does not require the installation of a salt bath (it only requires wetting the surface of the material to be treated by spraying, coating, etc.), so it is effective in reducing equipment costs, adjusting the concentration of the solution, and preventing scratches. has been done.
２）上記特公昭５２−４３７６６号公報の出願人により
、前記発明の技術思想を基本とし、焼鈍された被処理鋼
材が保有している熱を有効に利用するようさらに改良さ
れた方法として、特公昭５３−３４１６７号公報による
「ステンレス鋼の処理方法と題する」方法が提案された
。2) The applicant of the above-mentioned Japanese Patent Publication No. 52-43766 has proposed a method based on the technical idea of the above-mentioned invention, which is further improved to effectively utilize the heat possessed by the annealed steel material. A method entitled ``Method for treating stainless steel'' was proposed in Japanese Publication No. 53-34167.
この方法では第３図に示すように被処理材Ｗを焼鈍炉ｌ
で焼鈍した後、空冷あるいは強制空冷などの冷却設備２
３°により被処理材を６００〜９００℃程度まで冷却し
、苛性ソーダなどの苛性アルカリ又はオルソ珪酸、亜硝
酸などのアルカリ塩類の水溶液をストレージタンク３４
に溜め、スプレー装置２３のノズルの先端からスプレー
処理し、ステンレス鋼の保有熱を一部利用して、その表
面上で前記のアルカリ塩を瀉融点以上の温度で所定時間
反応させた後酸化帯３７を経て洗浄設備２８により水洗
脱スケールするか、必要に応じ酸洗タンク２９により硝
酸、硫酸、弗酸等の無機強酸を用いて脱スケールし洗滌
設備３１を通過させ製品とする。上記の２方法は、それ
までは不可欠とされた脱スケールでのソルトバスが不要
になる点を特徴とする。In this method, the workpiece W is placed in an annealing furnace as shown in Figure 3.
After annealing, use cooling equipment 2 such as air cooling or forced air cooling.
The material to be treated is cooled to about 600 to 900°C by 3 degrees, and an aqueous solution of a caustic alkali such as caustic soda or an alkali salt such as orthosilicic acid or nitrous acid is stored in a storage tank 34.
The alkali salt is collected in the stainless steel and sprayed from the tip of the nozzle of the spray device 23, and the alkali salt is reacted on the surface of the stainless steel at a temperature higher than the melting point for a predetermined period of time, using part of the heat retained in the stainless steel, and then an oxidation zone is formed. 37, the product is descaled by washing with water in the cleaning equipment 28, or if necessary, is descaled using a strong inorganic acid such as nitric acid, sulfuric acid, or hydrofluoric acid in the pickling tank 29, and then passed through the cleaning equipment 31 to form a product. The above two methods are characterized in that they do not require a salt bath for descaling, which was previously considered indispensable.
［発明が解決しようとする課題］
１）ソルトバスを使用する脱スケール方式では、温度の
管理が容易である反面、被処理材がソルトバスの浴面下
に設けたテンションロールと接触することにより発生す
るスクラッチキズ等が最大の問題であることは前項で述
べた。[Problems to be solved by the invention] 1) In the descaling method using a salt bath, temperature control is easy, but on the other hand, the material to be treated comes into contact with the tension roll installed under the bath surface of the salt bath, As mentioned in the previous section, the scratches, etc. that occur are the biggest problem.
２）一方、前記３の１）と２）によるスプレー処理方式
では、焼鈍炉から出た被処理材を所定の温度を下回らぬ
ように調整する必要があるが、板の厚さや幅により冷却
速度も異なり特に薄板では温度が低くなりやすいなど温
度調節が困難である。2) On the other hand, in the spray treatment method according to 1) and 2) of 3 above, it is necessary to adjust the temperature of the material to be treated after coming out of the annealing furnace so that it does not fall below a predetermined temperature, but the cooling rate may vary depending on the thickness and width of the plate. Temperature control is difficult, especially with thin plates, as the temperature tends to drop.
３）ステンレス鋼には、オーステナイト系、フェライト
系、マルテンサイト系、析出硬化系などの多くの鋼種が
ある。3) There are many types of stainless steel, such as austenitic, ferritic, martensitic, and precipitation hardening.
そのため、熱処理も多岐にわたり、ＪＩＳ鉄鋼規格によ
り、オーステナイト系については固溶化処理後急冷、フ
ェライト系では焼きなまし後急冷または徐冷、マルテン
サイト系では焼きなまし後は急冷または徐冷であるが、
焼き入れの際は加熱後急冷、析出硬化系では固溶化処理
の際には所定温度に保持された炉中から急冷し、その後
の析出硬化熱処理では所定の冷却速度で冷却するなど細
部にわたり規定されている。Therefore, heat treatments vary widely, and according to JIS steel standards, austenitic steels are rapidly cooled after solution treatment, ferritic steels are rapidly cooled or slowly cooled after annealing, and martensitic steels are rapidly cooled or slowly cooled after annealing.
During quenching, the material is rapidly cooled after heating; for precipitation hardening systems, during solution treatment, it is rapidly cooled in a furnace maintained at a predetermined temperature; and during subsequent precipitation hardening heat treatment, it is cooled at a predetermined cooling rate. ing.
このような鋼種によって異なる冷却条件により保持温度
から急冷を要する熱処理に対しては、前記の特公昭５３
−３４１６７号による焼鈍材の保有熱を利用する方法は
適用できないという問題があった。For heat treatment that requires rapid cooling from the holding temperature due to cooling conditions that differ depending on the steel type, the above-mentioned Japanese Patent Publication No. 53
There was a problem in that the method of utilizing the heat retained in the annealed material according to No. 34167 could not be applied.
４）また、前記公報の請求項２のようにアルカリ水溶液
スプレー後に、さらに酸化帯を設は脱スケールする方法
では、処理ラインの長さの増大を伴うという難点があっ
た。4) Furthermore, the method of descaling by further providing an oxidation zone after spraying the alkaline aqueous solution as claimed in claim 2 of the above-mentioned publication has the disadvantage that the length of the treatment line is increased.
［課題を解決するための手段］
本発明では、前項で述べたソルトバスによる場合にテン
ションロールとの接触によるスクラ・ンチキズや押し傷
の発生、アルカリ水溶液スプレーによる場合に、被処理
材の温度を所定範囲に保持することの困難性、溶体化処
理など加熱後の急冷を必要とする鋼種への適用不能など
の種々の課題を解決する手段として、焼鈍炉などから出
された被処理材を、進行方向に下向に傾斜した経路に沿
ってツルトスプレーゾーン内を進行させ、その間に３５
０〜４８０℃に保持したソルト供給タンクから、溶融ソ
ルトをパイプで送り、３３０〜４６０℃に保持されたス
プレーノズルから溶融ソルトとしてスプレーした後、少
なくとも１回水洗槽を通過させて、脱スケールするとい
う手段を採用して課題を解決した。[Means for Solving the Problems] In the present invention, the temperature of the material to be treated can be adjusted to prevent scratches and scratches caused by contact with the tension roll when using the salt bath described in the previous section, and when using an alkaline aqueous solution spray. As a means to solve various problems such as the difficulty of maintaining the material within a specified range and the inability to apply it to steel types that require rapid cooling after heating such as solution treatment, It travels through the Tsuruto spray zone along a path that is inclined downward in the direction of travel, and during that time
Molten salt is sent through a pipe from a salt supply tank maintained at 0 to 480°C, sprayed as molten salt from a spray nozzle maintained at 330 to 460°C, and then passed through a washing tank at least once to descale. This method was adopted to solve the problem.
［作 用１
焼鈍炉から出された被処理材は、ツルトスブレーゾーン
に送られ鋼材の温度の低下の程度に関係なく、はぼ３３
０〜４６０℃の温度でスプレーされる溶融ソルトによっ
て該ソルトと同一温度にされ、被処理材の表面が溶融ソ
ルトに十分濡らされた状態で、所定の時間移送される間
に脱スケールに必要な反応物質が形成され、余剰のソル
トは表面から下方に落下し、被処理材の表面に付着した
反応物質は水洗槽、スチーム、水などのスプレー処理に
より被処理材の表面から脱落し脱スケールが完了する。[Function 1: The material to be treated taken out of the annealing furnace is sent to the Tsuruto Brake Zone and is heated to about 33 degrees regardless of the degree of decrease in the temperature of the steel material.
The molten salt that is sprayed at a temperature of 0 to 460°C is brought to the same temperature as the salt, and while the surface of the material to be treated is sufficiently wetted with the molten salt, it is transferred for a predetermined period of time to remove the necessary amount for descaling. Reactants are formed and excess salt falls downward from the surface, and the reactants adhering to the surface of the material to be treated are removed from the surface of the material by washing with water, steam, water, etc., and descaling occurs. Complete.
［実施例］ 第１図を参照して本発明の詳細な説明する。[Example] The present invention will be described in detail with reference to FIG.
符号Ｗは被処理材で、この実施例ではＪＩＳＧ４３０７
のＳＵＳ ４３０ステンレス鋼帯を使用した。The code W is the material to be treated, and in this example, it is JIS G4307.
SUS 430 stainless steel strip was used.
被処理材を焼鈍炉ｌを通過させ８２０″Ｇに加熱した後
、炉外で大気中冷却しながらツルトスブレーゾーン２に
送り、この中では矢印Ａで示す進行方向に約３０度の角
度に傾斜した経路に沿って進行させ、その間被処理材の
上下両面を挟んで被処理材に平行に配置され４２０６Ｃ
に保持されたツルトスブレーノズル５から溶融状態のソ
ルトＳを被処理材Ｗの上下両面に吹き付けた。After passing through the annealing furnace 1 and heating the material to 820"G, the material to be treated is sent to the Tsuruto Brake Zone 2 while being cooled in the atmosphere outside the furnace, where it is tilted at an angle of about 30 degrees in the direction of movement shown by arrow A. The 4206C
The molten salt S was sprayed onto both the upper and lower surfaces of the material W to be treated from the sturt spray nozzle 5 held in the holder.
この溶融ソルトＳは、４５０°Ｃに保持されたソルト供
給タンク７から配管７゛を経て、ポンプＰ２により圧送
される。This molten salt S is pumped from a salt supply tank 7 maintained at 450° C. via a pipe 7′ by a pump P2.
ツルトスブレーノズル５は、ツルトスプレーゾーン２の
入り口近くにスプレーゾーン２の全長の約４分の１長さ
で傾斜して延在し、その直下の床１１は被処理材の経路
と同じ方向に、かつ、より緩い角度で傾斜し、被処理材
の表面から落下したソルトＳが温度の低下に伴って一時
的に凝固し集積することもあるが、後述する第１水洗槽
３からポンプＰＩにより汲み上げられてスプレーゾーン
２の入り口直下の床面１１の高い部分に加えられるソル
ト水溶液により渚解され、傾斜した床面の低い方（図で
右側）へ移動するようになっている。The Tsuruto spray nozzle 5 extends near the entrance of the Tsuruto spray zone 2 at an angle of approximately one quarter of the total length of the spray zone 2, and the floor 11 directly below it extends in the same direction as the path of the material to be treated. , and the salt S that falls from the surface of the material to be treated by tilting at a gentler angle may temporarily solidify and accumulate as the temperature decreases. The salt aqueous solution is pumped up and added to the high part of the floor 11 directly below the entrance to the spray zone 2, where it is dissolved and moved to the lower part of the sloping floor (to the right in the figure).
ツルトスプレーノズル５を通過した被処理材Ｗは、さら
に送られて前記の床１１に隣接して配置された第１水洗
槽３に導かれて水中に浸漬され、付着しているソルトを
脱落させるが、水中に浸漬される直前にスチームノズル
６から高温の蒸気が吹き付けられ水中に浸漬される以前
にソルトが脱落しやすいようにされている。The treated material W that has passed through the Tsuruto spray nozzle 5 is further sent to the first washing tank 3 disposed adjacent to the floor 11 and immersed in water to remove the salt attached thereto. However, just before being immersed in water, high-temperature steam is sprayed from a steam nozzle 6 to make it easier for the salt to fall off before being immersed in water.
第１水洗槽３の床面１３は、前記のツルトスプレーゾー
ン２の床１１の傾斜よりも傾斜がやや急にされ、更に床
１１の床面１３に近い部分には仕切り１２が設けられて
いる。The floor 13 of the first washing tank 3 has a slightly steeper slope than the floor 11 of the Tsuruto spray zone 2, and a partition 12 is provided in a portion of the floor 11 close to the floor 13. .
第１水洗槽３内で水中に浸漬されてソルトが除去された
被処理材Ｗは、ローラ１４により送り方向が上向きに変
えられて水面から離れ、第１水洗槽３の出口部に向うが
、中間に第２のスチーム（または水）ノズル６°が設け
られている。The treated material W, which has been immersed in water in the first washing tank 3 to have the salt removed, is moved upward by the rollers 14, away from the water surface, and toward the outlet of the first washing tank 3. A second steam (or water) nozzle 6° is provided in the middle.
第１水洗槽３から出された被処理材Ｗは、更に第２水洗
槽４に導かれるが第１水洗槽３と第２のスチーム（また
は水）ノズル６°によるソルトの脱落が十分な場合は第
２水洗槽４は省略できる。The material to be treated W discharged from the first washing tank 3 is further guided to the second washing tank 4, but when the salt is removed sufficiently by the first washing tank 3 and the second steam (or water) nozzle 6°. In this case, the second washing tank 4 can be omitted.
第１水洗槽３内の水には、被処理材Ｗから脱落あるいは
除去されたソルト成分が溶解されて、ソルトの水溶液に
なっているので、ポンプＰ４により水溶液をソルト回収
タンク８まで汲み上げ、補充用ソルトとして貯留してお
き、ソルト供給タンク７内のソルトが消耗して不足した
場合にポンプＰ３によりソルト供給タンク７まで汲み上
げ水溶液の状態で補給する。The water in the first washing tank 3 dissolves the salt components that have fallen off or been removed from the material W to be treated and becomes an aqueous solution of salt, so the aqueous solution is pumped up to the salt recovery tank 8 by the pump P4 and refilled. When the salt in the salt supply tank 7 is exhausted and becomes insufficient, the salt is pumped up to the salt supply tank 7 by the pump P3 and replenished in the form of an aqueous solution.
［効果］
１）本発明では、焼鈍炉などを出た被処理材にはは３３
０〜４６０°Ｃに保持されたツルトスブレーノズルから
溶融状態のソルトが被処理材の上下両面に吹き付けられ
るので、被処理材が室温程度にまで冷却された状態でも
、又ある程度高温に保持されている状態でも適用できる
ので、ステンレス鋼の各種の鋼種や各種熱処理のための
加熱後の脱スケールに対しても広く適用可能である。[Effects] 1) In the present invention, the treated material leaving the annealing furnace etc. contains 33
Since molten salt is sprayed onto both the upper and lower surfaces of the material to be treated from the Surutosuhure nozzle, which is maintained at a temperature of 0 to 460°C, even if the material to be treated has been cooled to around room temperature, it can still be maintained at a certain high temperature. Since it can be applied even in the state where it is present, it can be widely applied to various types of stainless steel and descaling after heating for various heat treatments.
２）また、ソルトの水溶液でなく溶融状態のソルトを使
用する方法でありながら、ソルトバスを使用せず、被処
理材を傾斜した経路に沿って移送する間に３３０〜４６
０°Ｃに保持されたツルトスブレーノズルから溶融状態
のソルトをスプレーするため、ソルトバスの浴面下をロ
ールで案内する必要がなく、ロールと被処理材の接触摩
擦によるスクラッチキズや押し傷等の発生を回避できる
。2) Although this method uses molten salt rather than an aqueous solution of salt, it does not use a salt bath and the material to be treated is transported along an inclined path while the
Since molten salt is sprayed from a sult spray nozzle kept at 0°C, there is no need to guide the surface of the salt bath with a roll, and there is no need to use a roll to guide the surface of the salt bath, eliminating scratches and pressure marks caused by contact friction between the roll and the treated material can be avoided.
３）溶融状態のソルトを供給するため４５０〜４８０℃
に保持したソルト供給タンクを使用するので、ソルト回
収タンク内のソルト水溶液をそのままの状態でソルト供
給タンクに少量ずつ滴下して補充することができる。3) 450-480℃ to supply molten salt
Since the salt supply tank is kept at a constant temperature, the aqueous salt solution in the salt recovery tank can be dripped into the salt supply tank little by little to be replenished.
４）以上の特徴に加え、装置全体を比較的狭いスペース
内に効率よく配置できる。4) In addition to the above features, the entire device can be efficiently arranged within a relatively narrow space.
第１図は、本発明の脱スケール装置を示す概略側面図、
第２図は、従来技術のソルトバス脱スケール装置を示す
概略側面図、第３図は、従来技術の水渚液ソルトによる
脱スケール装置を示す概略側面図である。
図面中の符号
１：焼鈍炉、 ２：ツルトスプレーゾーン、３：
第１水洗槽、 ４：第２水洗槽、
５：ツルトスブレーノズル、
６：スチームノズル、６°ニスチーム（水）ノズル７：
ソルト供給タンク、８：ソルト回収タンク、１１：床面
、１２：仕切り、１３：第１水洗槽の床面、１４：ロー
ル、Ｓ：ソルト、Ｗ：被処理材、Ｐｌ、Ｐ２．Ｐ３．Ｐ
４：ポンプ。
代理人 弁理士 藤 本 礒
代理人 弁理士 後 藤 武 夫FIG. 1 is a schematic side view showing the descaling device of the present invention;
FIG. 2 is a schematic side view showing a conventional salt bath descaling device, and FIG. 3 is a schematic side view showing a conventional descaling device using water salt. Code 1 in the drawing: Annealing furnace, 2: Tsuruto spray zone, 3:
1st washing tank, 4: 2nd washing tank, 5: Tsurutosuburai nozzle, 6: Steam nozzle, 6° Nisteam (water) nozzle 7:
Salt supply tank, 8: Salt recovery tank, 11: Floor surface, 12: Partition, 13: Floor surface of first washing tank, 14: Roll, S: Salt, W: Material to be treated, Pl, P2. P3. P
4: Pump. Agent Patent Attorney Isao Fujimoto Agent Patent Attorney Takeo Goto
Claims (6)
過して加熱され、表面に酸化被膜が形成された帯状のス
テンレス鋼の被処理処材を溶融状態のアルカリ性の塩に
より前記の酸化被膜を除去する脱スケール処理法におい
て、 供給タンク内に溶融塩を３５０〜４８０℃に保持し、前
記被処理材を進行方向に対し下向きに傾斜した状態で移
送している間に、前記供給タンクから溶融ソルトを送り
３３０〜４６０℃の温度で、ノズルから前記被処理材の
表面にスプレーして溶融塩の膜を形成して所定の時間反
応させ、 反応の終った被処理材を少なくとも一つの水洗槽を通過
させて急冷し、脱スケールすることを特徴とするステン
レス鋼の脱スケール方法。1. A strip of stainless steel is wound into a roll and heated through a metallurgical furnace such as an annealing furnace to form an oxide film on its surface.The oxide film is then removed using molten alkaline salt. In the descaling treatment method for removing Spray the molten salt onto the surface of the treated material from a nozzle at a temperature of 330 to 460°C to form a molten salt film and react for a predetermined time, and after the reaction, the treated material is washed with at least one water bath. A method for descaling stainless steel, which is characterized by passing it through a tank to rapidly cool it and descaling it.
に溶融塩の膜が形成された後、水洗槽を通過させる前に
空気、スチームまたは水により予冷させることを特徴と
するステンレス鋼の脱スケール方法。2. 2. The method according to claim 1, wherein after a film of molten salt is formed on the surface of the material to be treated, the material is pre-cooled with air, steam or water before passing through a washing tank. Method.
材が溶融塩の膜による所定の反応の終った後、第１の水
洗槽を通過させ、さらに前記被処理材を第２の水洗槽を
通過させ脱スケールすることを特徴とするステンレス鋼
の脱スケール方法。3. 3. The method according to claim 1, wherein after the material to be treated has undergone a predetermined reaction with a molten salt film, the material to be treated is passed through a first washing tank, and the material to be processed is further passed through a second washing tank. A method for descaling stainless steel, which is characterized by descaling.
て、被処理材にスプレーされた溶融塩の余剰分をノズル
の下方に落下させ、前記水洗槽内の水に、前記水洗槽で
のスケール除去処理により除去した成分と、前記ノズル
の下方に落下した溶融塩の余剰分とを溶解させ、前記の
溶融塩を溶解した水洗槽内の水溶液を供給タンク内に補
給することを特徴とするステンレス鋼の脱スケール方法
。4. In the method according to any one of claims 1 to 3, an excess amount of the molten salt sprayed on the material to be treated is dropped below a nozzle, and added to the water in the washing tank to remove scale in the washing tank. A stainless steel characterized in that the components removed by the treatment and the surplus of the molten salt that has fallen below the nozzle are dissolved, and the aqueous solution in the washing tank in which the molten salt is dissolved is replenished into the supply tank. Descaling method.
過して加熱され、表面に酸化被膜が形成された帯状のス
テンレス鋼の被処理処材をアルカリ性の溶融塩により前
記の酸化被膜を除去する脱スケール処理装置において、 前記帯状のステンレス鋼の被処理処材を進行方向に対し
下向きに傾斜した状態で移送する移送ラインと、 前記溶融塩を３５０〜４８０℃に保持するタンクと、前
記供給タンクから溶融ソルトを供給されて、３３０〜４
６０℃の温度に保持し、前記被処理材が前記移送ライン
内を下向きに傾斜して移送されている間に、前記被処理
材の表面に溶融塩をスプレーして溶融塩の膜を形成させ
るノズルと、 反応の終った被処理材を通過させて、スチーム又は水に
より予冷する予冷装置と、 脱スケールのための少くとも一つの水洗槽と、を備えて
成ることを特徴とするステンレス鋼の脱スケール装置。5. A strip of stainless steel that has been wound into a roll and heated through a metallurgical furnace such as an annealing furnace has an oxide film formed on its surface, and the oxide film is removed using an alkaline molten salt. A descaling treatment apparatus comprising: a transfer line that transfers the strip-shaped stainless steel material to be treated in a state inclined downward with respect to the traveling direction; a tank that maintains the molten salt at a temperature of 350 to 480°C; Supplied with molten salt from the tank, 330~4
Maintaining the temperature at 60° C. and spraying molten salt onto the surface of the material to be treated to form a film of molten salt while the material to be treated is being transferred in a downwardly inclined manner within the transfer line. A stainless steel apparatus comprising: a nozzle; a pre-cooling device for passing the treated material after reaction and pre-cooling it with steam or water; and at least one washing tank for descaling. Descaling equipment.
送ラインと、スプレーノズルと、一つの水洗槽とが１つ
のスプレーゾーン内に配置されて、前記スプレーノズル
は前記スプレーゾーンの入り口近くに、下向きに傾斜し
て移送される被処理材に平行に、その上下両面に溶融塩
を所定量だけスプレー可能な長さに配置され、 前記スプレーゾーン内の前記スプレーノズルよりも下流
側には、被処理材が水洗槽の浴面中に浸漬される位置の
前、または後の少なくとも一方の位置に、被処理材にス
チームまたは水をスプレーするノズルが設けられ、 前記スプレーゾーンの前記スプレーノズルの下方の床面
は、前記被処理材の表面にスプレーされた後、被処理材
の表面から落下した余剰の溶融塩を貯留するとともに、
水洗槽から加えられる溶融塩の水溶液に溶解されて前記
水洗槽内に流入可能な緩い傾斜面にされ、 前記スプレーゾーンの前記スプレーノズルより下流側の
床面は、前記スプレーノズルの下方の緩い傾斜の床面に
連続してさらに一層傾斜されて前記水洗槽の床面を形成
し、 前記水洗槽と保持タンクとの間には、水洗槽内の溶融塩
の水溶液を前記保持タンク内に水溶液の状態で補給する
ための配管などの輸送手段が設けられていることを特徴
とするステンレス鋼の脱スケール装置。6. 6. The descaling apparatus according to claim 5, wherein the transfer line, a spray nozzle, and a rinsing tank are arranged in a spray zone, and the spray nozzle is directed downwardly near the entrance of the spray zone. The spray nozzle is arranged parallel to the material to be treated, which is being transported at an angle, and has a length that allows a predetermined amount of molten salt to be sprayed on both the upper and lower surfaces of the material. A nozzle for spraying steam or water onto the treated material is provided at least one of the positions before or after the position where the material is immersed in the bath surface of the washing tank, and the floor below the spray nozzle of the spray zone is provided. The surface stores surplus molten salt that has fallen from the surface of the material to be treated after being sprayed onto the surface of the material to be treated, and
The molten salt aqueous solution added from the washing tank is dissolved into a gently sloped surface that can flow into the washing tank, and the floor surface on the downstream side of the spray nozzle of the spray zone has a gentle slope below the spray nozzle. The floor surface of the washing tank is further sloped continuously from the floor surface of the washing tank, and between the washing tank and the holding tank, the aqueous solution of the molten salt in the washing tank is transferred to the holding tank. A stainless steel descaling device characterized in that it is provided with a means of transportation such as piping for replenishing the stainless steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28829390A JP2949642B2 (en) | 1990-10-29 | 1990-10-29 | Stainless steel descaling method and equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28829390A JP2949642B2 (en) | 1990-10-29 | 1990-10-29 | Stainless steel descaling method and equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04165090A true JPH04165090A (en) | 1992-06-10 |
| JP2949642B2 JP2949642B2 (en) | 1999-09-20 |
Family
ID=17728284
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28829390A Expired - Lifetime JP2949642B2 (en) | 1990-10-29 | 1990-10-29 | Stainless steel descaling method and equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2949642B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994003651A2 (en) * | 1992-08-05 | 1994-02-17 | Kolene Corporation | Method, apparatus and salt for descaling metal strip |
| US5505786A (en) * | 1992-08-05 | 1996-04-09 | Kolene Corporation | Method for treating surface oxides on a metal alloy strip |
| TWI450976B (en) * | 2012-01-02 | 2014-09-01 | China Steel Corp | Induction heat treatment method of spring wire rod |
| CN107923050A (en) * | 2015-07-22 | 2018-04-17 | 寇林公司 | For optimizing the oxide skin adjusting method of high strength carbon steel alloy |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20150018086A (en) * | 2013-08-09 | 2015-02-23 | 주식회사 포스코 | cooling apparatus for metal strip |
-
1990
- 1990-10-29 JP JP28829390A patent/JP2949642B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994003651A2 (en) * | 1992-08-05 | 1994-02-17 | Kolene Corporation | Method, apparatus and salt for descaling metal strip |
| WO1994003651A3 (en) * | 1992-08-05 | 1994-08-18 | Kolene Corp | Method, apparatus and salt for descaling metal strip |
| US5505786A (en) * | 1992-08-05 | 1996-04-09 | Kolene Corporation | Method for treating surface oxides on a metal alloy strip |
| TWI450976B (en) * | 2012-01-02 | 2014-09-01 | China Steel Corp | Induction heat treatment method of spring wire rod |
| CN107923050A (en) * | 2015-07-22 | 2018-04-17 | 寇林公司 | For optimizing the oxide skin adjusting method of high strength carbon steel alloy |
| EP3325690A4 (en) * | 2015-07-22 | 2019-04-17 | Kolene Corporation | Scale conditioning process for advanced high strength carbon steel alloys |
| CN107923050B (en) * | 2015-07-22 | 2019-12-31 | 寇林公司 | Oxide skin adjusting method for optimizing high-strength carbon steel alloy |
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| Publication number | Publication date |
|---|---|
| JP2949642B2 (en) | 1999-09-20 |
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