JP2997971B2 - Method and apparatus for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion - Google Patents
Method and apparatus for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesionInfo
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- JP2997971B2 JP2997971B2 JP29198692A JP29198692A JP2997971B2 JP 2997971 B2 JP2997971 B2 JP 2997971B2 JP 29198692 A JP29198692 A JP 29198692A JP 29198692 A JP29198692 A JP 29198692A JP 2997971 B2 JP2997971 B2 JP 2997971B2
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Description
【０００１】[0001]
【産業上の利用分野】本発明は熱延鋼板にＺｎ、Ａｌ等
の１種または２種以上を主成分とする溶融めっきを施し
た鋼板の製造方法および製造装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a hot-rolled steel sheet in which hot-rolled steel sheet is hot-dip coated with at least one of Zn, Al and the like.
【０００２】[0002]
【従来の技術】従来、代表的な熱延めっき鋼帯としてＺ
ｎ系溶融めっき熱延鋼帯が知られており、その一般的製
造方法は、熱間圧延終了後コイル状に巻き取られ、１０
０℃未満に３〜４日かけて自然冷却された後、生成した
表面スケール除去（１０μｍ程度）のため酸洗ラインに
おいて８０℃程度で処理され、さらにその後、溶融めっ
きラインで処理される。なお、Ｚｎ系溶融めっき冷延鋼
板の場合は、酸洗と溶融めっきの間に冷間圧延が行われ
る。2. Description of the Related Art Conventionally, a typical hot-rolled steel strip is Z
An n-type hot-dip galvanized steel strip is known, and its general manufacturing method is to wind it into a coil after hot rolling, and
After being naturally cooled to less than 0 ° C. over 3 to 4 days, it is treated at about 80 ° C. in a pickling line to remove the generated surface scale (about 10 μm), and then further processed in a hot-dip plating line. In the case of a Zn-based hot-dip cold-rolled steel sheet, cold rolling is performed between pickling and hot-dip plating.
【０００３】また、溶融めっきラインとしては、鋼帯を
７００〜８００℃程度に加熱し、酸化性雰囲気ガス中で
酸洗工程およびその後の搬送時に鋼板表面に付着したス
マット等と呼ばれる異物（酸化鉄、水酸化鉄、塩化鉄、
珪酸塩等）、油脂等のめっき性を阻害する表面皮膜・汚
物を燃焼除去し、それらの高温での除去に伴って発生す
る鋼帯表面の酸化皮膜をさらに水素雰囲気ガス中で還元
することにより、めっき密着性に必要な表面清浄性を確
保し、その後非酸化性もしくは還元性雰囲気中でめっき
浴温近傍まで冷却して溶融めっきするいわゆるゼンジマ
ー法、あるいは鋼帯を７００〜８００℃程度に加熱し、
水素雰囲気ガス中で酸洗工程およびその後の搬送時に鋼
板表面に付着したスマット等と呼ばれる異物、油脂等の
めっき性を阻害する表面皮膜・汚物を除去し、めっき密
着性に必要な表面清浄性を確保し、その後非酸化性もし
くは還元性雰囲気中でめっき浴温近傍まで冷却して溶融
めっきするいわゆる無酸化炉法が採用されている。[0003] In a hot-dip plating line, a steel strip is heated to about 700 to 800 ° C, and a foreign substance called iron (smut) or the like adhered to the steel sheet surface during the pickling step and the subsequent transportation in an oxidizing atmosphere gas. , Iron hydroxide, iron chloride,
By burning and removing surface films and dirt that inhibit the plating properties such as silicates, oils and fats, and reducing the oxide film on the steel strip surface resulting from their removal at high temperature in a hydrogen atmosphere gas. A so-called Zenzimer method in which the surface cleanliness necessary for plating adhesion is ensured, and then cooled to a temperature near the plating bath temperature in a non-oxidizing or reducing atmosphere and hot-dip plating is performed, or a steel strip is heated to about 700 to 800 ° C. And
Removes surface films and contaminants, such as smut, that adhere to the steel plate surface during the pickling process and subsequent transportation in a hydrogen atmosphere gas and impede the plating properties such as oil and grease, and improves the surface cleanliness required for plating adhesion. A so-called non-oxidizing furnace method is adopted in which the temperature is secured and then cooled to a temperature near the plating bath temperature in a non-oxidizing or reducing atmosphere to perform hot-dip plating.
【０００４】[0004]
【発明が解決しようとする課題】しかるに、めっき密着
性に必要な表面清浄性を確保するために、コイルを３〜
４日かけて１００℃未満へ冷却した後酸洗し、７００〜
８００℃程度の高温まで再加熱する従来方法は、コイル
の広大な冷却スペース、膨大な再加熱エネルギー・長大
な加熱炉を必要とするため、操業コスト負担が大きく、
長い製造工期を必要とする。However, in order to secure the surface cleanliness required for plating adhesion, the coils must be 3 to 3 mm.
After being cooled to less than 100 ° C. over 4 days,
The conventional method of reheating to a high temperature of about 800 ° C. requires a large cooling space for the coil, a huge amount of reheating energy and a long heating furnace, so that the operation cost burden is large,
Requires a long manufacturing period.
【０００５】[0005]
【課題を解決するための手段】本発明はコイルの保有熱
を利用し、酸洗工程を省略して連続的に表面清浄化手段
である還元処理、温度調整、めっきを行い、かつ、少な
くとも還元処理完了以降めっき直前までは非酸化性もし
くは還元性に雰囲気調整することにより、鋼板の温度調
整および表面清浄化に要する熱エネルギー・設備を小さ
くし、巻取り以降の所要時間を短縮し、在庫金利、在庫
スペースを極小化することにより納期短縮と操業コスト
低減を達成するとともに、すぐれためっき密着性を得る
ことを可能とする。本発明の要旨は以下の通りである。According to the present invention, a reduction treatment, a temperature adjustment, and a plating, which are surface cleaning means, are continuously performed by omitting an pickling step by utilizing heat retained in a coil, and at least reducing the surface. By adjusting the atmosphere to non-oxidizing or reducing before and just before plating, heat energy and equipment required for temperature adjustment and surface cleaning of the steel sheet are reduced, the time required after winding is shortened, and inventory interest rates are reduced. By minimizing the inventory space, it is possible to shorten delivery times and reduce operating costs, and to obtain excellent plating adhesion. The gist of the present invention is as follows.
【０００６】（１）熱間圧延され、巻取られたコイルを
対象として、１００℃以上での巻戻し、６００℃以上で
の還元処理、６００℃以下へのめっき前温度調整、溶融
めっきを連続的に行い、かつ少なくとも還元処理完了以
降めっき直前までを非酸化性もしくは還元性に雰囲気調
整することを特徴とするめっき密着性に優れた熱延溶融
めっき鋼帯の製造方法。(1) Unwinding at a temperature of 100 ° C. or more, reduction treatment at a temperature of 600 ° C. or more, temperature adjustment before plating to 600 ° C. or less, and hot-dip plating are continuously performed on a hot-rolled and wound coil. A method for producing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion, wherein the atmosphere is adjusted to non-oxidizing or reducing at least from the completion of the reduction treatment to immediately before plating.
【０００７】（２）熱間圧延され、巻取られたコイルを
対象として、１００℃以上で巻戻しを実施する設備、６
００℃以上で還元処理を実施する設備、６００℃以下に
めっき前温度を調整する設備、溶融めっきを行う設備を
順次設け、かつ少なくとも還元処理完了以降めっき直前
までを非酸化性もしくは還元性に雰囲気調整する設備を
有するめっき密着性に優れた熱延溶融めっき鋼帯の製造
装置。(2) Equipment for performing unwinding at 100 ° C. or higher for hot-rolled and wound coils, 6
Equipment for performing the reduction treatment at 00 ° C or higher, equipment for adjusting the pre-plating temperature to 600 ° C or lower, and equipment for hot-dip plating are sequentially provided. Equipment for manufacturing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion and equipment for adjusting.
【０００８】（３）熱間圧延され、巻取られたコイルを
対象として、１００℃以上での巻戻しおよび歪付加、６
００℃以上での還元処理、６００℃以下へのめっき前温
度調整、溶融めっきを連続的に行い、かつ少なくとも還
元処理完了以降めっき直前までを非酸化性もしくは還元
性に雰囲気調整することを特徴とするめっき密着性に優
れた熱延溶融めっき鋼帯の製造方法。(3) Unwinding and adding strain at 100 ° C. or higher for the coil that has been hot-rolled and wound;
A reduction treatment at a temperature of 00 ° C. or higher, a pre-plating temperature adjustment to 600 ° C. or lower, and a hot-dip plating are continuously performed, and the atmosphere is adjusted to a non-oxidizing or reducing atmosphere at least from the completion of the reduction treatment to immediately before the plating. Of hot-rolled hot-dip galvanized steel strip with excellent plating adhesion.
【０００９】（４）熱間圧延され、巻取られたコイルを
対象として、１００℃以上で巻戻しおよび歪付加を実施
する設備、６００℃以上で還元処理を実施する設備、６
００℃以下にめっき前温度を調整する設備、溶融めっき
を行う設備を順次設け、かつ少なくとも還元処理完了以
降めっき直前までを非酸化性もしくは還元性に雰囲気調
整する設備を有するめっき密着性に優れた熱延溶融めっ
き鋼帯の製造装置。(4) Equipment for performing unwinding and strain addition at 100 ° C. or more for a hot-rolled and wound coil, equipment for performing reduction treatment at 600 ° C. or more, 6
Equipment for adjusting the pre-plating temperature to 00 ° C or less, equipment for hot-dip plating are sequentially provided, and equipment for adjusting the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment to immediately before plating is excellent in plating adhesion. Hot rolled hot-dip galvanized steel strip manufacturing equipment.
【００１０】（５）熱間圧延され、巻取られたコイルを
対象として、１００℃以上での巻戻し、６００℃以上で
の還元処理、６００℃以下へのめっき前温度調整および
表面調整、溶融めっきを連続的に行い、かつ少なくとも
還元処理完了以降めっき直前までを非酸化性もしくは還
元性に雰囲気調整することを特徴とするめっき密着性に
優れた熱延溶融めっき鋼帯の製造方法。(5) Unwinding at a temperature of 100 ° C. or more, reduction treatment at a temperature of 600 ° C. or more, temperature adjustment before plating to 600 ° C. or less, surface adjustment, and melting of a hot-rolled and wound coil A method for producing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion, wherein plating is continuously performed and the atmosphere is adjusted to a non-oxidizing or reducing atmosphere at least from the completion of the reduction treatment to immediately before the plating.
【００１１】（６）熱間圧延され、巻取られたコイルを
対象として、１００℃以上で巻戻しを実施する設備、６
００℃以上で還元処理を実施する設備、６００℃以下に
めっき前温度を調整する設備および表面調整する設備、
溶融めっきを行う設備を順次設け、かつ少なくとも還元
処理完了以降めっき直前までを非酸化性もしくは還元性
に雰囲気調整する設備を有するめっき密着性に優れた熱
延溶融めっき鋼帯の製造装置。(6) equipment for performing unwinding at a temperature of 100 ° C. or higher for a coil that has been hot-rolled and wound;
Equipment for performing a reduction treatment at 00 ° C or higher, equipment for adjusting the temperature before plating to 600 ° C or lower, and equipment for surface adjustment.
An apparatus for manufacturing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion, comprising equipment for sequentially performing hot-dip plating and equipment for adjusting the atmosphere to a non-oxidizing or reducing atmosphere at least from the completion of the reduction treatment to immediately before the plating.
【００１２】（７）熱間圧延され、巻取られたコイルを
対象として、１００℃以上での巻戻しおよび歪付加、６
００℃以上での還元処理、６００℃以下へのめっき前温
度調整および表面調整、溶融めっきを連続的に行い、か
つ少なくとも還元処理完了以降めっき直前までを非酸化
性もしくは還元性に雰囲気調整することを特徴とするめ
っき密着性に優れた熱延溶融めっき鋼帯の製造方法。(7) Unwinding and straining at 100 ° C. or higher for the coil that has been hot-rolled and wound;
Continuously perform reduction treatment at 00 ° C or more, temperature adjustment and surface adjustment before plating to 600 ° C or less, and hot-dip plating, and adjust the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment to immediately before plating. A method for producing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion.
【００１３】（８）熱間圧延され、巻取られたコイルを
対象として、１００℃以上で巻戻しおよび歪付加を実施
する設備、６００℃以上で還元処理を実施する設備、６
００℃以下にめっき前温度を調整する設備および表面調
整する設備、溶融めっきを行う設備を順次設け、かつ少
なくとも還元処理完了以降めっき直前までを非酸化性も
しくは還元性に雰囲気調整する設備を有するめっき密着
性に優れた熱延溶融めっき鋼帯の製造装置。(8) Equipment for performing unwinding and strain addition at 100 ° C. or more for a hot-rolled and wound coil, equipment for performing reduction treatment at 600 ° C. or more, 6
Plating with equipment for adjusting the temperature before plating to less than 00 ° C, equipment for adjusting the surface, equipment for hot-dip plating, and equipment for adjusting the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment until immediately before the plating. Manufacturing equipment for hot-rolled hot-dip galvanized steel strip with excellent adhesion.
【００１４】（９）連続熱間圧延の仕上圧延工程におい
て、下記の式数３を満足するように仕上圧延終了温度、
巻取温度及び仕上圧延終了から巻取までの時間を制御す
ることを特徴とする前記（１）、（３）、（５）または
（７）のめっき密着性に優れた熱延溶融めっき鋼帯の製
造方法。(9) In the finish rolling step of continuous hot rolling, the finish rolling end temperature is set so as to satisfy the following equation (3).
The hot-rolled hot-dip galvanized steel strip having excellent plating adhesion according to the above (1), (3), (5) or (7), wherein the winding temperature and the time from the finish rolling to the winding are controlled. Manufacturing method.
【００１５】[0015]
【数３】 ０．０２７×ＦＴ＋０．０００１８×（ＦＴ＋ＣＴ）×ｔ≦２７．２ ただし、ＦＴ：仕上圧延終了温度（℃） ＣＴ：巻取温度（℃） ｔ ：仕上圧延終了から巻取までの時間（秒）[Formula 3] 0.027 × FT + 0.00018 × (FT + CT) × t ≦ 27.2 where FT: finish rolling end temperature (° C.) CT: winding temperature (° C.) t: from the end of finish rolling to winding up Time (seconds)
【００１６】（１０）連続熱間圧延の仕上圧延工程にお
いて、下記の式数４を満足するように仕上圧延終了温
度、巻取温度及び仕上圧延終了から巻取までの時間を制
御することを特徴とする前記（２）、（４）、（６）ま
たは（８）のめっき密着性に優れた熱延溶融めっき鋼帯
の製造装置。(10) In the finishing rolling step of continuous hot rolling, the finishing rolling temperature, the winding temperature and the time from finishing finishing to winding are controlled so as to satisfy the following equation (4). (2), (4), (6) or (8), an apparatus for producing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion.
【００１７】[0017]
【数４】 ０．０２７×ＦＴ＋０．０００１８×（ＦＴ＋ＣＴ）×ｔ≦２７．２ ただし、ＦＴ：仕上圧延終了温度（℃） ＣＴ：巻取温度（℃） ｔ ：仕上圧延終了から巻取までの時間（秒）## EQU00004 ## where 0.027.times.FT + 0.00018.times. (FT + CT) .times.t.ltoreq.27.2 where FT: finish rolling finish temperature (.degree. C.) CT: winding temperature (.degree. C.) t: from the end of finish rolling to winding. Time (seconds)
【００１８】[0018]
【作用】以下、本発明について詳細に説明する。Hereinafter, the present invention will be described in detail.
【００１９】（１）鋼板化学成分 本発明において、鋼板化学成分は特に限定されるもので
はなく、必要とされる加工特性・用途に応じて適宜選択
が可能である。例えば、Ｃ、Ｓｉ、Ｍｎ、Ａｌを基本成
分とする低炭素系軟鋼、さらに上記基本成分にＮｂ、Ｔ
ｉ、Ｃｒ、Ｐ、Ｃａ、Ｖ、Ｃｕ、Ｍｏ等の１種または２
種以上を添加した高張力鋼、加工用鋼の適用が可能であ
る。(1) Steel sheet chemical composition In the present invention, the steel sheet chemical composition is not particularly limited, and can be appropriately selected according to the required processing characteristics and applications. For example, low-carbon mild steel containing C, Si, Mn, and Al as basic components, and Nb, T
one or two of i, Cr, P, Ca, V, Cu, Mo, etc.
High-strength steel and steel for processing to which more than one kind is added can be applied.
【００２０】（２）圧延素材 本発明において、圧延素材は特に限定されるものではな
いが、例えば通常の連続鋳造スラブ、薄肉の連続鋳造ス
ラブが適用できる。また、圧延素材の熱履歴としてスラ
ブを一旦冷却した後再び加熱する再加熱法のみならず、
いわゆるダイレクト・ローリング（ＤＲ）法の適用も可
能である。(2) Rolled Material In the present invention, the rolled material is not particularly limited, and for example, a normal continuous cast slab or a thin continuous cast slab can be applied. Also, as a heat history of the rolled material, not only the reheating method of once cooling and then heating the slab again,
It is also possible to apply a so-called direct rolling (DR) method.
【００２１】（３）熱間圧延条件 本発明において、熱間圧延条件は（例えば、加熱温度、
熱間圧延温度、熱間圧延圧下率、ホットランテーブルで
の冷却履歴）必要とされる加工特性・用途に応じて適宜
選択が可能である。ただし、好ましくは還元性およびめ
っき性向上の観点から、スケールを薄くすべく、熱間圧
延条件を限定することが望ましい。以下にその詳細を述
べる。(3) Hot Rolling Conditions In the present invention, hot rolling conditions include (for example, heating temperature,
Hot rolling temperature, hot rolling reduction, cooling history with hot run table) It can be appropriately selected according to required processing characteristics and applications. However, it is desirable to limit the hot rolling conditions so as to make the scale thinner, preferably from the viewpoint of improving the reducibility and the plating property. The details are described below.
【００２２】表１に示すＡ鋼を主体として、仕上圧延終
了温度、巻取温度、仕上圧延終了から巻取までの時間が
スケール厚へ及ぼす影響について検討した結果、図１に
示すように仕上圧延終了温度の低下、巻取温度の低下、
仕上圧延終了から巻取までの時間の短縮により、スケー
ル厚は薄くなることおよび仕上圧延終了温度が高いほ
ど、巻取温度が高いほど、仕上圧延終了から巻取までの
時間の増加によるスケール厚増大作用は大きくなること
を知見した。さらに、図２に示すようにそれらの条件を
下記式数５に示す特定範囲内に制御することにより、
安定確実にスケール厚を制御することが可能であること
を知見した。すなわち、下記式を満足することによ
り、薄いスケールとすることができるため、還元性およ
びめっき性の向上が可能となる。さらに一層の向上を考
慮した場合、式で右辺の値を２５．２以下とし一層薄
いスケールとすることがより望ましい。As a result of examining the effects of the finish rolling temperature, the winding temperature, and the time from the finish rolling to the winding on the scale thickness using the steel A shown in Table 1 as a main component, as shown in FIG. Lower end temperature, lower winding temperature,
The scale thickness is reduced by shortening the time from finish rolling to winding, and the scale thickness is increased by increasing the time from finishing rolling to winding as the finishing rolling temperature is higher and the winding temperature is higher. The effect was found to be greater. Further, as shown in FIG. 2, by controlling those conditions within a specific range represented by the following equation 5,
It was found that the scale thickness can be controlled stably and reliably. That is, by satisfying the following expression, a thin scale can be obtained, so that the reducibility and the plating property can be improved. In consideration of the further improvement, it is more preferable to set the value on the right side of the equation to 25.2 or less to make the scale thinner.
【００２３】[0023]
【表１】 [Table 1]
【００２４】[0024]
【数５】 ０．０２７×ＦＴ＋０．０００１８×（ＦＴ＋ＣＴ）×ｔ≦２７．２… ただし、ＦＴ：仕上圧延終了温度（℃） ＣＴ：巻取温度（℃） ｔ ：仕上圧延終了から巻取までの時間（秒）[Formula 5] 0.027 × FT + 0.00018 × (FT + CT) × t ≦ 27.2 where FT: Finish rolling finish temperature (° C.) CT: Winding temperature (° C.) t: From finish rolling to winding Time (seconds)
【００２５】スケール厚をより薄くするために仕上圧延
開始温度≦１０００℃とする方法、スケール厚をより薄
くするために仕上圧下率≧９０％とする方法、スケール
厚をより薄くするために仕上圧延終了後１秒以内に水冷
を開始する方法、還元性の悪いＦｅ3 Ｏ4 の生成を極力
抑えるために鋼板温度がＦｅＯからＦｅ3 Ｏ4 への変態
開始温度である５７５℃近傍になった時点から還元開始
までの時間を短縮する方法の１つあるいは２つ以上を実
施することはより効果的である。A method in which the finish rolling start temperature ≦ 1000 ° C. to make the scale thickness thinner, a method in which the finish rolling reduction ≧ 90% in order to make the scale thickness thinner, and a finish rolling in order to make the scale thickness thinner Method of starting water cooling within 1 second after completion, at the time when the temperature of the steel sheet becomes close to 575 ° C., which is the transformation start temperature from FeO to Fe 3 O 4 , in order to minimize the generation of Fe 3 O 4 with poor reducibility It is more effective to carry out one or more of the methods for reducing the time from the start to the reduction.
【００２６】また、熱間圧延機出側に近接した巻取装置
（いわゆる近接コイラー）を用いて、コイルの保有熱の
最大活用、仕上圧延終了から巻取までの時間の短縮をは
かることも可能であるし、Ａｒ、Ｎ2 等の不活性雰囲気
中での圧延、スケール生成抑制作用を有する溶媒を含む
冷却水を使用した圧延スタンド間やホットランテーブル
上での冷却、巻取ったコイルのＮ2 シール雰囲気ボック
ス内での冷却、フェライト域圧延、圧延直後急冷などの
採用も可能である。Also, by using a winding device (so-called proximity coiler) close to the exit side of the hot rolling mill, it is possible to make maximum use of the heat possessed by the coil and to shorten the time from finishing rolling to winding. And rolling in an inert atmosphere such as Ar or N 2 , cooling between rolling stands or on a hot run table using cooling water containing a solvent having an action of suppressing scale formation, and N 2 of a wound coil. Cooling in a sealed atmosphere box, ferrite zone rolling, rapid cooling immediately after rolling, etc. can also be employed.
【００２７】（４）コイル巻戻し条件 コイル巻戻しは１００℃以上で実施しなければならな
い。１００℃未満では、コイルの広大な冷却スペース、
膨大な再加熱エネルギー・長大な加熱炉を必要とするた
め、操業コスト負担が大きく、製造工期が長くなる。ま
た、還元効率の向上、外観品位の向上を目的として巻戻
しに際して歪付加を行ってもよい。(4) Coil unwinding condition Coil unwinding must be performed at 100 ° C. or higher. If the temperature is lower than 100 ° C., a vast cooling space for the coil,
Since a huge amount of reheating energy and a long heating furnace are required, the operating cost burden is large and the manufacturing period is long. Further, distortion may be added at the time of rewinding for the purpose of improving the reduction efficiency and the appearance quality.
【００２８】スキンパス、テンションレベラー、ベンデ
ィングロール等による歪付加により、スケールが脱落し
たり、スケール中へクラックが導入されるために、還元
効率が向上する。また、歪付加により鋼板表面に歪模様
が細かいピッチで多数発生するため、通板時の曲げ曲げ
戻し等に伴う鋼板の変形により発生する腰折れと称され
る外観品位を害する歪模様が無害化され、外観品位が向
上する。[0028] The scale is dropped or cracks are introduced into the scale due to the addition of distortion by a skin pass, a tension leveler, a bending roll, or the like, so that the reduction efficiency is improved. In addition, since many strain patterns are generated at a fine pitch on the surface of the steel sheet due to the addition of strain, distortion patterns that degrade the appearance quality called waist breaks caused by deformation of the steel sheet due to bending and returning during passing are made harmless. The appearance quality is improved.
【００２９】（５）還元処理条件 還元処理は６００℃以上で実施しなければならない。６
００℃未満では還元反応が緩慢となり、未還元スケール
が残存し、めっき密着性および耐食性を害する。(5) Reduction treatment conditions The reduction treatment must be performed at 600 ° C. or higher. 6
If the temperature is lower than 00 ° C., the reduction reaction becomes slow, and unreduced scale remains, impairing plating adhesion and corrosion resistance.
【００３０】（６）還元処理後の工程条件 還元処理により得られためっき密着性に必要な表面清浄
性を維持ないしはその効果をより高めるため、還元処理
完了後、連続的に非酸化性もしくは還元性雰囲気中で６
００℃以下にめっき前板温調整を行い、めっきを行う。(6) Process conditions after the reduction treatment In order to maintain the surface cleanliness required for the adhesion of the plating obtained by the reduction treatment or to enhance the effect thereof, after the reduction treatment is completed, the non-oxidizing or reduction is continuously performed. 6 in a sexual atmosphere
Pre-plating temperature is adjusted below 00 ° C to perform plating.
【００３１】６００℃超ではＺｎとＦｅの合金化反応が
過度に進行し、Γ相等の脆いめっき層が出現し、めっき
密着性を劣化させる。還元手段としては水素プラズマ、
Ｈ2＋Ｎ2 ガス、直火バーナーによる直火還元等を利用
できる。If the temperature exceeds 600 ° C., the alloying reaction between Zn and Fe proceeds excessively, and a brittle plating layer such as a Γ phase appears to deteriorate the plating adhesion. Hydrogen plasma,
H 2 + N 2 gas, direct flame reduction by direct flame burner, etc. can be used.
【００３２】なお、本発明によれば、鋼板表面にポーラ
スな鉄層が存在するため、低温かつ短時間のめっき浴と
の反応で密着性のよいめっき層の生成が可能である。According to the present invention, since a porous iron layer is present on the surface of the steel sheet, it is possible to form a plating layer having good adhesion by reacting with a plating bath at a low temperature for a short time.
【００３３】温度調整設備としてはいわゆるラジアント
チューブ式炉のみならず、設備コンパクト化、熱応答
性、還元能等の観点から、通電加熱、直火還元、誘導加
熱等の急速加熱装置の採用が可能である。As the temperature control equipment, not only a so-called radiant tube furnace, but also rapid heating equipment such as electric heating, direct flame reduction, induction heating, etc. can be adopted from the viewpoint of equipment compactness, thermal responsiveness, reducing ability, etc. It is.
【００３４】さらに、上記めっき密着性の改善、後述の
合金化処理時の合金化特性の改善を目的にめっき前にブ
ラシ研磨、スキンパス圧下等の表面調整手段を採用する
ことも可能であり、めっき完了後、必要とされる特性・
用途に応じて、いわゆる合金化処理、スキンパス、クロ
メート処理、ボンデ処理、塗装などの種々の後処理を１
種ないしは２種以上適宜選択することが可能である。Further, for the purpose of improving the plating adhesion and the alloying characteristics at the time of the alloying treatment described later, it is possible to employ a surface adjusting means such as brush polishing or skin pass pressure reduction before plating. After completion, required characteristics
Depending on the application, various post-treatments such as so-called alloying treatment, skin pass, chromate treatment, bond treatment, and painting can be performed.
The species or two or more species can be appropriately selected.
【００３５】また、溶融めっき方法として、浴中への鋼
帯浸漬のみならず、ロールコーター、スプレー、電磁ポ
ンプ等による浴の持ち上げ等を利用することも可能であ
り、本発明を真空蒸着、イオンプレーティング等へ利用
することも可能である。As the hot-dip plating method, not only immersion of the steel strip in the bath but also lifting of the bath by a roll coater, spray, electromagnetic pump or the like can be used. It can also be used for plating and the like.
【００３６】[0036]
実施例１ 表２に示す化学成分を有する鋼片を連続鋳造により製造
し、表３に示す条件で溶融Ｚｎ−０．２％Ａｌ〜５％Ａ
ｌめっき熱延鋼板を製造した。なお、還元前のスケール
厚、スケール組成を表４に示す。Example 1 A slab having the chemical components shown in Table 2 was produced by continuous casting, and molten Zn-0.2% Al to 5% A under the conditions shown in Table 3.
A 1-plated hot-rolled steel sheet was manufactured. Table 4 shows the scale thickness and scale composition before reduction.
【００３７】[0037]
【表２】 [Table 2]
【００３８】[0038]
【表３】 [Table 3]
【００３９】[0039]
【表４】 [Table 4]
【００４０】不めっきの有無を目視で、めっき密着性は
落重式デュポン（ＤＵＰＯＮＴ）衝撃試験機（落下高
さ：５０ｃｍ、落下重量：２７ｋｇ重、ポンチ形状：φ
１０×５ｍｍ、ダイス径：φ２０）で加工後のめっき剥
離状況を目視で、腰折れを目視で評価した。なお、評価
はめっき後３０日経過してから実施した。いずれも不め
っきがなく、優れためっき密着性を示し、腰折れも認め
られず、良好なめっき製品が得られた。The presence or absence of non-plating was visually observed, and the plating adhesion was measured by a dropping-type DuPont impact tester (drop height: 50 cm, drop weight: 27 kg weight, punch shape: φ)
(10 × 5 mm, die diameter: φ20) The plating peeling state after processing was visually evaluated, and the waist break was visually evaluated. The evaluation was performed 30 days after plating. In each case, there was no non-plating, excellent plating adhesion was exhibited, no break was observed, and good plated products were obtained.
【００４１】さらに、裸耐食性、塗装耐食性を塩水噴霧
試験で、化成処理性を化成皮膜付着量で、塗装密着性を
エリクセン試験で評価したが、いずれの特性も良好であ
った。Further, the bare corrosion resistance and the coating corrosion resistance were evaluated by a salt spray test, the chemical conversion treatment property was evaluated by a conversion film adhesion amount, and the coating adhesion was evaluated by an Erichsen test, and all properties were good.
【００４２】実施例２ 図３、４に本発明の製造装置の例を示す。Embodiment 2 FIGS. 3 and 4 show an example of the manufacturing apparatus of the present invention.
【００４３】[0043]
【発明の効果】本発明により、Ｚｎ系溶融めっき熱延鋼
板製造に要する熱エネルギー・設備を小さくし、巻取り
以降の所要日数を短縮し、操業コストを低減しつつ、良
好なめっき密着性を得ることが可能となり、産業上、そ
の効果は極めて大きい。According to the present invention, it is possible to reduce the heat energy and equipment required for manufacturing a hot-rolled Zn-based hot-rolled steel sheet, shorten the number of days required after winding, reduce the operating cost, and improve the adhesion of the plating. It can be obtained, and the effect is extremely large industrially.
【図１】ＦＴ、ＣＴおよびｔとスケール厚の関係を示す
図である。FIG. 1 is a diagram showing the relationship between FT, CT, and t and scale thickness.
【図２】式とスケール厚の関係を示す図である。FIG. 2 is a diagram showing a relationship between an equation and a scale thickness.
【図３】本発明の製造装置の例を示す図である。FIG. 3 is a diagram showing an example of a manufacturing apparatus of the present invention.
【図４】本発明の製造装置の例を示す図である。FIG. 4 is a diagram showing an example of the manufacturing apparatus of the present invention.
【図５】本発明の製造方法の熱履歴の例を従来法と比較
した模式図である。FIG. 5 is a schematic diagram comparing an example of a thermal history of the manufacturing method of the present invention with a conventional method.
【図６】歪付加装置の例としてベンディングロールを示
す図である。FIG. 6 is a diagram illustrating a bending roll as an example of a distortion applying device.
１ 熱間圧延 ２ ホットランテーブル ３ コイル ４ 保温台車 ８ ペイオフリール ９ 歪付加装置 １０ シャー １１ ウェルダー １２ 入側ルーパー １３ トリマー １４ ブラッシング １８ 還元処理＋温度調整 １９ 表面調整装置 ２０ めっきポット ２１ 合金化炉 ２２ 気水冷却部 ２３ スキンパス ２４ テンションレベラー ２５ クロメート処理 ２６ 出側ルーパー ２７ オイラー ２８ 検査床 ２９ シャー ３０ テンションリール ３１ コイル ３２ ベンディングロール ３３ 鋼板 REFERENCE SIGNS LIST 1 hot rolling 2 hot run table 3 coil 4 warming trolley 8 payoff reel 9 distortion applying device 10 shear 11 welder 12 entry side looper 13 trimmer 14 brushing 18 reduction treatment + temperature adjustment 19 surface adjustment device 20 plating pot 21 alloying furnace 22 gas Water cooling unit 23 Skin pass 24 Tension leveler 25 Chromate treatment 26 Outgoing looper 27 Euler 28 Inspection floor 29 Shear 30 Tension reel 31 Coil 32 Bending roll 33 Steel plate
フロントページの続き (72)発明者 小倉 正美 大分県大分市大字西ノ洲１ 新日本製鐵 株式会社 大分製鐵所内 (72)発明者 山崎 二郎 大分県大分市大字西ノ洲１ 新日本製鐵 株式会社 大分製鐵所内 (72)発明者 加藤 秀夫 大分県大分市大字西ノ洲１ 新日本製鐵 株式会社 大分製鐵所内 (72)発明者 江坂 一彬 愛知県東海市東海町５−３ 新日本製鐵 株式会社 名古屋製鐵所内 (72)発明者 土師 純治 大分県大分市大字西ノ洲１ 新日本製鐵 株式会社 大分製鐵所内 (72)発明者 河野 治 大分県大分市大字西ノ洲１ 新日本製鐵 株式会社 大分製鐵所内 (58)調査した分野(Int.Cl.7，ＤＢ名) C23C 2/00 - 2/40 B21B 1/26 Continued on the front page (72) Inventor Masami Ogura Oishi, Oita-shi, Oita Prefecture, Nishi-no-Susu 1 Nippon Steel Corporation Oita Works (72) Inventor Jiro Yamazaki 1, Oita-shi, Oita-shi, Oita Oita-shi Ozai, Nippon Steel Corporation Oita Inside the Iron Works (72) Inventor Hideo Kato 1 Nishinosu, Oita, Oita City, Oita Prefecture Inside Nippon Steel Corporation Oita Works (72) Inventor Kazuaki Esaka 5-3 Tokaicho, Tokai City, Aichi Prefecture Nippon Steel Nagoya Corporation Inside the steelworks (72) Inventor Junji Hashi, Oita-shi, Oita, Oita, Oita Prefecture Nippon Steel Corporation Oita Works (72) Inventor, Osamu Kawano, Oita-shi, Oita, Oita Prefecture, Oaza, 1 Nippon Steel Corporation Nippon Steel Corporation Oita Steel Corporation In-house (58) Field surveyed (Int. Cl. 7 , DB name) C23C 2/00-2/40 B21B 1/26
Claims (10)
として、１００℃以上での巻戻し、６００℃以上での還
元処理、６００℃以下へのめっき前温度調整、溶融めっ
きを連続的に行い、かつ少なくとも還元処理完了以降め
っき直前までを非酸化性もしくは還元性に雰囲気調整す
ることを特徴とするめっき密着性に優れた熱延溶融めっ
き鋼帯の製造方法。1. Continuously unwinding at a temperature of 100 ° C. or more, reducing at a temperature of 600 ° C. or more, adjusting the temperature before plating to 600 ° C. or less, and hot-dip coating the hot-rolled and wound coil. A hot-rolled hot-dip galvanized steel strip having excellent plating adhesion, wherein the atmosphere is adjusted to a non-oxidizing or reducing atmosphere at least from the completion of the reduction treatment to immediately before the plating.
として、１００℃以上で巻戻しを実施する設備、６００
℃以上で還元処理を実施する設備、６００℃以下にめっ
き前温度を調整する設備、溶融めっきを行う設備を順次
設け、かつ少なくとも還元処理完了以降めっき直前まで
を非酸化性もしくは還元性に雰囲気調整する設備を有す
るめっき密着性に優れた熱延溶融めっき鋼帯の製造装
置。2. A facility for performing unwinding at a temperature of 100 ° C. or higher for a coil that has been hot-rolled and wound,
Equipment for performing reduction treatment at a temperature of ℃ or higher, equipment for adjusting the pre-plating temperature to 600 ° C or less, and equipment for hot-dip plating are sequentially provided, and the atmosphere is adjusted to non-oxidizing or reducing at least from the completion of the reduction treatment until immediately before plating. Equipment for manufacturing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion.
として、１００℃以上での巻戻しおよび歪付加、６００
℃以上での還元処理、６００℃以下へのめっき前温度調
整、溶融めっきを連続的に行い、かつ少なくとも還元処
理完了以降めっき直前までを非酸化性もしくは還元性に
雰囲気調整することを特徴とするめっき密着性に優れた
熱延溶融めっき鋼帯の製造方法。3. Unwinding and applying strain at 100 ° C. or higher for a coil that has been hot-rolled and wound,
The method is characterized in that a reduction treatment at a temperature of at least 100 ° C., a pre-plating temperature adjustment to 600 ° C. or less, and a hot-dip plating are performed continuously, and the atmosphere is adjusted to a non-oxidizing or reducing atmosphere at least from the completion of the reduction treatment until immediately before plating. A method for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion.
として、１００℃以上で巻戻しおよび歪付加を実施する
設備、６００℃以上で還元処理を実施する設備、６００
℃以下にめっき前温度を調整する設備、溶融めっきを行
う設備を順次設け、かつ少なくとも還元処理完了以降め
っき直前までを非酸化性もしくは還元性に雰囲気調整す
る設備を有するめっき密着性に優れた熱延溶融めっき鋼
帯の製造装置。4. A facility for performing unwinding and strain addition at 100 ° C. or higher for a hot-rolled and wound coil, a facility for performing reduction treatment at 600 ° C. or higher,
Equipment for adjusting the pre-plating temperature below ℃ and equipment for hot-dip plating in order, and equipment for adjusting the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment to immediately before plating. Equipment for manufacturing hot-dip galvanized steel strip.
として、１００℃以上での巻戻し、６００℃以上での還
元処理、６００℃以下へのめっき前温度調整および表面
調整、溶融めっきを連続的に行い、かつ少なくとも還元
処理完了以降めっき直前までを非酸化性もしくは還元性
に雰囲気調整することを特徴とするめっき密着性に優れ
た熱延溶融めっき鋼帯の製造方法。5. A method for unwinding at a temperature of 100 ° C. or more, a reduction treatment at a temperature of 600 ° C. or more, a temperature adjustment before plating to 600 ° C. or less and a surface adjustment, and hot-dip plating for a coil that has been hot-rolled and wound. A hot-rolled hot-dip steel strip having excellent plating adhesion, wherein the atmosphere is adjusted to non-oxidizing or reducing at least from the completion of the reduction treatment to immediately before the plating.
として、１００℃以上で巻戻しを実施する設備、６００
℃以上で還元処理を実施する設備、６００℃以下にめっ
き前温度を調整する設備および表面調整する設備、溶融
めっきを行う設備を順次設け、かつ少なくとも還元処理
完了以降めっき直前までを非酸化性もしくは還元性に雰
囲気調整する設備を有するめっき密着性に優れた熱延溶
融めっき鋼帯の製造装置。6. An apparatus for performing unwinding at a temperature of 100 ° C. or more for a coil that has been hot-rolled and wound,
Equipment to carry out the reduction treatment at a temperature of ℃ or more, equipment to adjust the temperature before plating to 600 ℃ or less, equipment to adjust the surface, equipment to perform hot-dip plating, and at least the non-oxidizing or A hot-rolled hot-dip galvanized steel strip manufacturing equipment with excellent plating adhesion, which has equipment for adjusting the atmosphere to reduce.
として、１００℃以上での巻戻しおよび歪付加、６００
℃以上での還元処理、６００℃以下へのめっき前温度調
整および表面調整、溶融めっきを連続的に行い、かつ少
なくとも還元処理完了以降めっき直前までを非酸化性も
しくは還元性に雰囲気調整することを特徴とするめっき
密着性に優れた熱延溶融めっき鋼帯の製造方法。7. Unwinding and applying strain at a temperature of 100 ° C. or more for a hot-rolled and wound coil;
It is necessary to continuously perform reduction treatment at a temperature of at least 100 ° C., temperature adjustment and surface adjustment before plating to 600 ° C. or less, and hot-dip plating, and adjust the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment until immediately before plating. A method for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion.
として、１００℃以上で巻戻しおよび歪付加を実施する
設備、６００℃以上で還元処理を実施する設備、６００
℃以下にめっき前温度を調整する設備および表面調整す
る設備、溶融めっきを行う設備を順次設け、かつ少なく
とも還元処理完了以降めっき直前までを非酸化性もしく
は還元性に雰囲気調整する設備を有するめっき密着性に
優れた熱延溶融めっき鋼帯の製造装置。8. A facility for performing unwinding and strain addition at 100 ° C. or higher for a hot-rolled and wound coil, a facility for performing reduction treatment at 600 ° C. or higher,
Equipment for adjusting the pre-plating temperature below ℃, equipment for adjusting the surface, equipment for hot-dip plating, and equipment for adjusting the atmosphere to non-oxidizing or reducing at least from the completion of the reduction treatment until immediately before plating. Equipment for hot-rolled hot-dip galvanized steel strip with excellent heat resistance.
下記の式数１を満足するように仕上圧延終了温度、巻取
温度及び仕上圧延終了から巻取までの時間を制御するこ
とを特徴とする請求項１、３、５または７記載のめっき
密着性に優れた熱延溶融めっき鋼帯の製造方法。 【数１】 ０．０２７×ＦＴ＋０．０００１８×（ＦＴ＋ＣＴ）×ｔ≦２７．２ ただし、ＦＴ：仕上圧延終了温度（℃） ＣＴ：巻取温度（℃） ｔ ：仕上圧延終了から巻取までの時間（秒）9. In the finish rolling step of continuous hot rolling,
The plating adhesion according to claim 1, 3, 5 or 7, wherein the finish-rolling end temperature, the winding temperature and the time from the finish-rolling end to winding are controlled so as to satisfy the following equation (1). Method for producing hot-rolled hot-dip galvanized steel strip with excellent performance. [Formula 1] 0.027 × FT + 0.00018 × (FT + CT) × t ≦ 27.2 where FT: Finish rolling finish temperature (° C.) CT: Winding temperature (° C.) t: From finish rolling to winding up Time (seconds)
て、下記の式数２を満足するように仕上圧延終了温度、
巻取温度及び仕上圧延終了から巻取までの時間を制御す
ることを特徴とする請求項２、４、６または８記載のめ
っき密着性に優れた熱延溶融めっき鋼帯の製造装置。 【数２】 ０．０２７×ＦＴ＋０．０００１８×（ＦＴ＋ＣＴ）×ｔ≦２７．２ ただし、ＦＴ：仕上圧延終了温度（℃） ＣＴ：巻取温度（℃） ｔ ：仕上圧延終了から巻取までの時間（秒）10. In the finish rolling step of continuous hot rolling, the finish rolling end temperature is set so as to satisfy the following equation (2).
9. The apparatus for producing a hot-rolled hot-dip galvanized steel strip having excellent plating adhesion according to claim 2, wherein the winding temperature and the time from finish rolling to winding are controlled. [Formula 2] 0.027 × FT + 0.00018 × (FT + CT) × t ≦ 27.2 where FT: Finish rolling finish temperature (° C.) CT: Winding temperature (° C.) t: From finish rolling to winding Time (seconds)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29198692A JP2997971B2 (en) | 1992-10-07 | 1992-10-07 | Method and apparatus for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29198692A JP2997971B2 (en) | 1992-10-07 | 1992-10-07 | Method and apparatus for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06116695A JPH06116695A (en) | 1994-04-26 |
| JP2997971B2 true JP2997971B2 (en) | 2000-01-11 |
Family
ID=17776040
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29198692A Expired - Lifetime JP2997971B2 (en) | 1992-10-07 | 1992-10-07 | Method and apparatus for producing hot-rolled hot-dip galvanized steel strip with excellent plating adhesion |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2997971B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3444117B2 (en) * | 1996-12-06 | 2003-09-08 | Ｊｆｅスチール株式会社 | Manufacturing method of hot-dip hot-rolled steel sheet |
| TW418122B (en) * | 1998-12-29 | 2001-01-11 | Po Hang Iron & Steel | Method for manufacturing hot rolled galvanized steel sheet at high speed, with pickling skipped |
| JP4543566B2 (en) * | 2001-03-08 | 2010-09-15 | Ｊｆｅスチール株式会社 | Manufacturing method of hot-dip galvanized steel sheet with excellent press formability |
| DE102008010062A1 (en) * | 2007-06-22 | 2008-12-24 | Sms Demag Ag | Process for hot rolling and heat treatment of a strip of steel |
| CN112143993B (en) * | 2019-06-26 | 2023-06-02 | 宝山钢铁股份有限公司 | Continuous hot galvanizing plating process method and equipment with post-plating dehydrogenation function |
-
1992
- 1992-10-07 JP JP29198692A patent/JP2997971B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06116695A (en) | 1994-04-26 |
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