JPH03211289A - Method for chromating zinc plated steel sheet - Google Patents
Method for chromating zinc plated steel sheetInfo
- Publication number
- JPH03211289A JPH03211289A JP450390A JP450390A JPH03211289A JP H03211289 A JPH03211289 A JP H03211289A JP 450390 A JP450390 A JP 450390A JP 450390 A JP450390 A JP 450390A JP H03211289 A JPH03211289 A JP H03211289A
- Authority
- JP
- Japan
- Prior art keywords
- chromate
- soln
- solution
- replenishment
- chromating
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 20
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 10
- 239000010959 steel Substances 0.000 title claims abstract description 10
- 239000011701 zinc Substances 0.000 title claims description 20
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 title claims description 13
- 229910052725 zinc Inorganic materials 0.000 title claims description 13
- 238000004532 chromating Methods 0.000 title abstract 7
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 claims abstract description 74
- 238000006243 chemical reaction Methods 0.000 claims description 23
- 229910001335 Galvanized steel Inorganic materials 0.000 claims description 9
- 239000008397 galvanized steel Substances 0.000 claims description 9
- 229910045601 alloy Inorganic materials 0.000 abstract description 2
- 239000000956 alloy Substances 0.000 abstract description 2
- 239000007788 liquid Substances 0.000 description 37
- 239000011651 chromium Substances 0.000 description 20
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 15
- 229910052804 chromium Inorganic materials 0.000 description 15
- 239000000203 mixture Substances 0.000 description 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 239000002253 acid Substances 0.000 description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 5
- 229910017604 nitric acid Inorganic materials 0.000 description 5
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 4
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 4
- 150000007513 acids Chemical class 0.000 description 3
- 230000009257 reactivity Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000003672 processing method Methods 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000003788 bath preparation Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007739 conversion coating Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- -1 pl+ Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000008213 purified water Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、亜鉛めっき鋼板及び亜鉛系合金めっき鋼板の
クロメート処理方法に関するものであり、対象とするク
ロメート処理としては、塗布クロメート、反応クロメー
ト電解クロメート処理等がある。[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for chromate treatment of galvanized steel sheets and zinc-based alloy coated steel sheets. There is chromate treatment, etc.
〈従来の技術〉
亜鉛めっき鋼板等の後処理として行われる化成処理方法
として、硫酸と無水クロム酸又はクロム酸塩との混合か
らなるクロメート処理液に鋼板を浸漬する、あるいはク
ロメート処理液を鋼板にスプレーする方法が知られてい
る。亜鉛めっき鋼板にクロメート処理する際、亜鉛めっ
き鋼板中の亜鉛がクロメート処理液中に溶出する。この
溶出した亜鉛がクロメート反応に影響を及ぼし、特に第
２図に示す様にクロメート処理液中の亜鉛が増加するこ
とにより、クロメート付着量が減少する。<Prior art> As a chemical conversion treatment method performed as a post-treatment for galvanized steel sheets, etc., steel sheets are immersed in a chromate treatment solution consisting of a mixture of sulfuric acid and chromic anhydride or chromate, or a chromate treatment solution is applied to steel sheets. A method of spraying is known. When a galvanized steel sheet is subjected to chromate treatment, the zinc in the galvanized steel sheet is eluted into the chromate treatment solution. This eluted zinc affects the chromate reaction, and in particular, as shown in FIG. 2, as the zinc in the chromate treatment solution increases, the amount of chromate deposited decreases.
そこで、クロメート付着量を一定に保つためには、クロ
メート液中の亜鉛濃度を一定に保てばよく、クロメート
処理中、クロメート液を徐々に棄て、新液を補給するオ
ートドレン方式が採用されている。Therefore, in order to keep the amount of chromate deposited constant, it is sufficient to keep the zinc concentration in the chromate solution constant. During chromate treatment, an auto-drain method is adopted in which the chromate solution is gradually discarded and new solution is replenished. There is.
従来のオートドレン方式は、新液の補給により、オート
ドレンによるクロメート液消費量に加えて亜鉛めっき鋼
板のクロメート反応によるクロメ−ト液消費量を同時に
まかない、クロメート液の量濃度を一定に保つ方式であ
る。そして、新液はｐＨ制御用補給液とクロム濃度制ｊ
ｌＩ用補給液から構成される。The conventional auto-drain method is a method that maintains the volume and concentration of chromate solution at a constant level by replenishing new solution to simultaneously cover the amount of chromate solution consumed by auto-drain and the amount of chromate solution consumed by the chromate reaction of galvanized steel sheets. It is. The new solution is a pH control replenishment solution and a chromium concentration control solution.
Consists of lI replenishment fluid.
ところが、オートドレンによるクロメート液消費に見合
う補給ｆＩｆの濃度バランス（ｐＨ補給用液、クロム濃
度補給用液）と、亜鉛めっき鋼板へのクロメート反応に
よるクロメート液消費に見合う補給液量の濃度バランス
（ｐｔｌ捕給月給用液ロム濃度補給用液）とが異なって
いるために、１つの新液供給で、両方の濃度バランスを
保つのは困難である。特にクロム濃度補給用液には、ク
ロム酸及びそれ以外の酸が含まれているため、クロム濃
度補給用液を補給しても、ｐｌ＋も若干かわり、ｐｌ＋
補給用液の補給量予測が困難となる。また、ｐＨ補給用
液は従来硝酸あるいはその他の酸であり、クロム濃度補
給用液はクロム酸及びそれ以外の酸が含まれているため
、オートドレンによる消費に見合う補給量とクロメート
反応による消費に見合う補給量のバランスが変わると、
処理液中の酸のバランスがくずれ、クロメート反応性あ
るいは析出物の構造が変わる可能性がある。However, the concentration balance of replenishment fIf (pH replenishment liquid, chromium concentration replenishment liquid) that corresponds to the chromate liquid consumption by auto drain, and the concentration balance of the replenishment liquid amount that corresponds to the chromate liquid consumption due to chromate reaction on galvanized steel sheets (ptl Since the monthly supply liquid (ROM concentration replenishment liquid) and the monthly supply liquid (ROM concentration replenishment liquid) are different from each other, it is difficult to maintain the balance of both concentrations by supplying one new liquid. In particular, the chromium concentration replenishment liquid contains chromic acid and other acids, so even if you replenish the chromium concentration replenishment liquid, pl+ will change slightly, and pl+
It becomes difficult to predict the amount of replenishment liquid. In addition, the pH replenishment liquid is conventionally nitric acid or other acids, and the chromium concentration replenishment liquid contains chromic acid and other acids, so the amount of replenishment commensurate with the consumption by auto drain and the consumption by chromate reaction. When the balance of appropriate supply changes,
The acid balance in the processing solution may be disrupted, and the chromate reactivity or structure of the precipitate may change.
因みに第３図は、次の条件で亜鉛めっき鋼板をクロメー
ト処理したときの、処理液中のクロム酸濃度、ｐ＋＋な
らびにＺｎ”濃度の経時的変化を示すものである。Incidentally, FIG. 3 shows the changes over time in the chromic acid concentration, p++, and Zn'' concentration in the treatment solution when a galvanized steel sheet was subjected to chromate treatment under the following conditions.
クロメート処理条件
クロメート処理液
組成（開始時） Ｃｒ”
１０ｇ／１
１０ｇ／１
２．０
５０ °Ｃ
ｌ２Ｏｍｐ霧
４．５ ｓｅｃ
スプレー法
１００ ｍｇ／イ
〜 １５ｇ／／！
１．２ｍ
１５に１
１．０ ｍ’／ｈｒ
Ｚｎ”
ｐＨ（開始時）
温度
ライン速度
処理時間
処理法
目標Ｃｒ付着量（設定値）
Ｚｎ”“の管理限界 ５
板幅
クロメート反応槽中液量
ドレン液量
間隔 連続
補給液
Ｃｒ”補給液 クロム酸、硫酸、硝酸、リン酸等
ｐＨ補給液 硝酸等
この第３図より処理液中のクロム濃度とｐＨがドレイン
による液消費量を補給するときに大きく変化しているこ
とがわかる。Chromate treatment conditions Chromate treatment liquid composition (at start) Cr” 10g/1 10g/1 2.0 50 °C 12Omp mist 4.5 sec Spray method 100mg/I ~ 15g//! 1.2m 1 in 15 1. 0 m'/hr Zn" pH (at start) Temperature line speed Processing time Processing method Target Cr deposition amount (set value) Zn"" control limit 5 Plate width Chromate reaction tank liquid volume Drain liquid volume interval Continuous replenishment liquid Cr Replenishment liquid: Chromic acid, sulfuric acid, nitric acid, phosphoric acid, etc. pH Replenishment liquid: Nitric acid, etc. From Figure 3, it can be seen that the chromium concentration and pH in the processing liquid change greatly when replenishing the amount of liquid consumed by the drain. .
〈発明が解決しようとする課題〉
本発明の目的は、クロメート処理液中の溶出亜鉛濃度を
管理限界に保ちながら操業するドレイン方式の亜鉛系め
っき鋼板のクロメート処理方法において、クロメート処
理液中のクロム濃度やｐＨの変動の小さいクロメート処
理液の補給方法を堤案することである。<Problems to be Solved by the Invention> The purpose of the present invention is to provide a drain-type chromate treatment method for zinc-plated steel sheets that operates while maintaining the eluted zinc concentration in the chromate treatment solution within a control limit. The aim is to propose a method for replenishing the chromate treatment solution with small fluctuations in concentration and pH.
く課題を解決するための手段〉
本発明は、クロメート処理液中に亜鉛系めっき鋼板を連
続的に通過させてクロメート処理する際にクロメート処
理液中に溶出した亜鉛濃度を一定に保つために所定量の
クロメート処理液を排出して新たな液を補給するオート
ドレン方式において、このオートドレンによるクロメー
ト液消費量を、クロメート反応によるクロメート液消費
量を補給するタンクとは別のサービスタンクより補給す
ることを特徴とする亜鉛系めっき鋼板のクロメート処理
方法である。Means for Solving the Problems> The present invention provides a method for keeping the concentration of zinc eluted into the chromate treatment solution constant when chromate treatment is performed by continuously passing a zinc-based plated steel sheet through the chromate treatment solution. In the auto-drain method, which drains a fixed amount of chromate treatment solution and replenishes it with new fluid, the amount of chromate solution consumed by this auto-drain is replenished from a service tank that is separate from the tank that replenishes the amount of chromate solution consumed by the chromate reaction. This is a method for chromate treatment of zinc-based plated steel sheets.
〈作用〉
本発明では、オートドレンによるクロメート液消費に見
合う補給液と、クロメート反応によるクロメート液消費
に見合う補給液と、２系統持ち、それぞれの濃度制御を
行うことができるので、クロム濃度とｐｎを一定に保つ
ことができ、なおかつｐ）Ｉを維持している酸のバラン
スもくずれることがない、その結果常に安定した反応性
、化成皮膜の組成が得られる。<Function> The present invention has two systems, one for the chromate solution consumed by auto-drain, and the other for the chromate solution consumed by the chromate reaction, and the concentration of each can be controlled, so that the chromium concentration and pn can be kept constant, and the acid balance that maintains p)I is not disrupted.As a result, stable reactivity and composition of the chemical conversion coating can be obtained at all times.
第１図に本発明のクロメート液の補給系統を示す、オー
トドレンによるクロメート液消費に見合う補給液の系統
Ｂ（実際に反応槽に入っている液の各成分バランスと同
じ液：濃縮液あるいは同じ液でもよい）と、クロメート
反応によるクロメート液消費に見合う補給液の系統Ａの
２系統からなっている。Figure 1 shows the chromate solution replenishment system of the present invention. System B of the replenishment solution that matches the chromate solution consumption by auto drain (a solution with the same component balance as the solution actually in the reaction tank: concentrated solution or the same There are two systems: system A, which is a replenishing liquid that is compatible with the consumption of chromate liquid by the chromate reaction.
オートドレンによるクロメート液消費は、反応槽と同じ
濃度のクロメート液消費であるから、反応槽の俗世レベ
ルに応して補給する。この補給液は、反応槽と同じ濃度
の液が本来なら望ましいが、補給液槽の容量が大きくな
るため濃縮液とし水との混合補給により消￥１量に見合
う量を補給する。Since the chromate solution consumed by auto drain is the same concentration of chromate solution as the reaction tank, it is replenished according to the normal level of the reaction tank. It is originally desirable that this replenishment liquid has the same concentration as that of the reaction tank, but since the capacity of the replenishment liquid tank becomes large, the concentrated liquid is mixed with water and replenished in an amount equivalent to the amount consumed per yen.
ここでクロム、 ｐｌ＋、水を１タンクずつ別々に貯蔵
してもよいし、各液を混合して貯蔵してもよい。Here, chromium, pl+, and water may be stored separately in one tank each, or each liquid may be mixed and stored.
クロメート反応によるクロメート液消費は、クロメート
の反応！（つまりクロメート皮膜量）により決まるもの
であるから、クロメートの反応量を予測して、補給する
かあるいはクロム濃度、ｐＨ等を測定して不足分を補給
するか、いずれの場合でも良い、クロメート反応量の予
測法は特公昭６０２４１８２号公報、特開昭５９−９３
８８３号公報等に開示されている。この場合の補給系統
はクロム補給用ｐＨ補給用と２種類でも良いし、反応に
よる消費よりクロムとｐＨの消費バランスを考慮して混
合した１種類のみでも良い。Chromate solution consumption due to chromate reaction is a chromate reaction! (In other words, the amount of chromate film), so either you can predict the reaction amount of chromate and replenish it, or you can measure the chromium concentration, pH, etc. and replenish the shortage. The method for predicting the amount is disclosed in Japanese Patent Publication No. 6024182 and Japanese Patent Application Laid-open No. 59-93.
It is disclosed in Publication No. 883 and the like. In this case, there may be two types of replenishment systems, one for chromium replenishment and one for pH replenishment, or only one type may be used, which is mixed in consideration of the consumption balance of chromium and pH rather than consumption by reaction.
次に実施例に基づいて本発明を説明する。Next, the present invention will be explained based on examples.
〈実施例〉
第１図に示すクロメート液補給系統を用し１で、亜鉛め
っき鋼板に下記の条件でクロメート処理した。その結果
を第４図に示す。<Example> Using the chromate solution replenishment system shown in FIG. 1, a galvanized steel sheet was subjected to chromate treatment under the following conditions. The results are shown in FIG.
クロメート処理条件
クロメート処理液
組成（開始時） Ｃｒ”
１０ｇ／ｊ！
１０ｇ／／！
２．０
５０ ’Ｃ
ｌ２Ｏｍｐ＋ｍ
４．５ ｓｅｃ
スプレー法
１１００ＩＩ１／ポ
〜 １５ｇ／ｊｌ！
１．２ｍ
５ ｋｌ
１．０ ｍ”／ｈｒ
Ｚｎ”
ｐｎ（開始時）
温度
ライン速度
処理時間
処理法
目標Ｃｒ付着量
Ｚｎ”の管理限界 ５
牟反輻
クロメート反応槽中液量
ドレン液量
間隔 連続
補給液
Ａ系統（クロメート反応による消耗対応）クロム補給タ
ンクの組成
りロム酸、硫酸、硝酸、リン酸等
補給量 ０．５ ｆｆｉ／閉１ｎｐＨ
補給タンクの組成
硝酸など
補給量 ２ ｊ！／＋＊ｉｎＢ系統（
ドレインによる消耗に対応）
クロム・ｐｌ＋補給タンクの組成
建浴剤と同じ組成（ただしＺｎなし）
補給１ ４ｏｚ７回
純水の補給量 １６０ ｆｆｉ／回第４図から
、Ｚｎ”濃度は管理範囲にあり、クロム濃度とｐＨ値も
一定に保たれていることが分る。Chromate treatment conditions Chromate treatment liquid composition (at start) Cr” 10g/j! 10g//! 2.0 50'Cl2Omp+m 4.5 sec Spray method 1100II1/po ~ 15g/jl! 1.2m 5 kl 1.0 m"/hr Zn" pn (at start) Temperature line speed Processing time Processing method Target Cr deposition amount Zn" control limit 5 Mutual radiation Chromate reaction tank liquid volume Drain liquid volume interval Continuous replenishment liquid A system (based on chromate reaction Consumables) Composition of chromium replenishment tank: Romic acid, sulfuric acid, nitric acid, phosphoric acid, etc. Replenishment amount: 0.5 ffi/closed 1npH
Composition of replenishment tank Replenishment amount of nitric acid, etc. 2 j! /+*inB strain (
Composition of chromium/PL + replenishment tank Same composition as bath preparation agent (but without Zn) Replenishment 1 4oz 7 times Purified water replenishment amount 160 ffi/time From Figure 4, the Zn” concentration is within the control range It can be seen that the chromium concentration and pH value were also kept constant.
〈発明の効果〉
本発明の２系統持った液補給方法を用いることによりク
ロム濃度、ｐＨを一定に保つことができクロメート反応
の反応性つまり皮膜量及び皮膜組成を一定に保つことが
できるようになり、品質安定への寄与は大きい。<Effects of the Invention> By using the two-system liquid replenishment method of the present invention, the chromium concentration and pH can be kept constant, and the reactivity of the chromate reaction, that is, the film amount and film composition, can be kept constant. This makes a great contribution to quality stability.
第１図は本発明のクロメート反応槽への補給液系統を示
す説明図、第２図は反応時間に対するクロメート皮膜量
及び浴中亜鉛濃度変化を示すグラフ、第３図は従来のオ
ートドレンによるｅ濃度バランスの変化を示すグラフ、
第４図は本発明の補給方法による液濃度バランスの変化
を示すグラフである。Fig. 1 is an explanatory diagram showing the replenishment liquid system to the chromate reaction tank of the present invention, Fig. 2 is a graph showing changes in the amount of chromate film and zinc concentration in the bath with respect to reaction time, and Fig. 3 is an explanatory diagram showing the replenishment liquid system for the chromate reaction tank of the present invention. Graph showing changes in concentration balance,
FIG. 4 is a graph showing changes in liquid concentration balance due to the replenishment method of the present invention.
Claims (1)
過させてクロメート処理する際にクロメート処理液中に
溶出した亜鉛濃度を一定に保つために所定量のクロメー
ト処理液を排出して新たな液を補給するオートドレン方
式において、このオートドレンによるクロメート液消費
量を、クロメート反応によるクロメート液消費量を補給
するタンクとは別のサービスタンクより補給することを
特徴とする亜鉛系めっき鋼板のクロメート処理方法。When chromate treatment is performed by continuously passing a zinc-based plated steel sheet through the chromate treatment solution, a predetermined amount of the chromate treatment solution is drained and a new solution is added in order to maintain a constant concentration of zinc eluted into the chromate treatment solution. A chromate treatment method for galvanized steel sheet, characterized in that in an auto-drain system for replenishment, the amount of chromate solution consumed by this auto-drain is replenished from a service tank different from the tank that replenishes the amount of chromate solution consumed by the chromate reaction. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP450390A JPH03211289A (en) | 1990-01-16 | 1990-01-16 | Method for chromating zinc plated steel sheet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP450390A JPH03211289A (en) | 1990-01-16 | 1990-01-16 | Method for chromating zinc plated steel sheet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03211289A true JPH03211289A (en) | 1991-09-17 |
Family
ID=11585860
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP450390A Pending JPH03211289A (en) | 1990-01-16 | 1990-01-16 | Method for chromating zinc plated steel sheet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03211289A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5161761B2 (en) * | 2006-02-17 | 2013-03-13 | ディップソール株式会社 | Treatment solution for forming black trivalent chromium conversion coating on zinc or zinc alloy and method for forming black trivalent chromium conversion coating on zinc or zinc alloy |
-
1990
- 1990-01-16 JP JP450390A patent/JPH03211289A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5161761B2 (en) * | 2006-02-17 | 2013-03-13 | ディップソール株式会社 | Treatment solution for forming black trivalent chromium conversion coating on zinc or zinc alloy and method for forming black trivalent chromium conversion coating on zinc or zinc alloy |
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