TWI589866B - Test piece for monitoring pitting corrosion, apparatus for monitoring pitting corrosion, and method for monitoring pitting corrosion - Google Patents
Test piece for monitoring pitting corrosion, apparatus for monitoring pitting corrosion, and method for monitoring pitting corrosion Download PDFInfo
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Description
本發明係關於一種評價水系統的金屬材料中產生的孔蝕的進展狀況的孔蝕監控測試件(test piece)。更詳細而言，關於一種可藉由結構性設計而提高孔蝕監控精度的孔蝕監控用測試件、使用該孔蝕監控用測試件的孔蝕監控裝置以及孔蝕監控方法。 The present invention relates to a pitting monitoring test piece for evaluating the progress of pitting corrosion generated in a metallic material of a water system. More specifically, the present invention relates to a test piece for pitting monitoring which can improve the accuracy of pitting monitoring by a structural design, a pitting monitoring device using the pitting monitoring test piece, and a pitting monitoring method.
水系統中的配管或熱交換器等存在使用金屬材料的情況。於此情形時，金屬製構件中局部腐蝕進展，孔蝕深度增加，且若此情形達到貫通程度，則存在產生設備作業停止等意外事態的情況。 The use of a metal material exists in piping, heat exchangers, etc. in a water system. In this case, local corrosion progresses in the metal member, and the pitting depth increases, and if the situation reaches the penetration level, there is a case where an unexpected situation such as a stop of the operation of the apparatus occurs.
作為防止水系統中的金屬製構件的孔蝕的技術，例如於專利文獻1揭示有藉由使用如下組成的銅合金製造冷熱水供給用配管而獲得耐孔蝕性優異的配管的技術，該組成的銅合金含有Zr：0.005重量%~1重量%，進而視需要含有P：0.005重量%~ 0.5重量%、以總量計為0.05重量%~5重量%的Sn、Ag中的一種或兩種、及以總量計為0.005重量%~1重量%的選自Ti、R的一種或兩種以上的元素，剩餘部分包括Cu及不可避免雜質。 As a technique for preventing pitting corrosion of a metal member in a water system, for example, Patent Document 1 discloses a technique for obtaining a pipe having excellent pitting resistance by producing a cold and hot water supply pipe using a copper alloy having the following composition. The copper alloy contains Zr: 0.005 wt% to 1 wt%, and further contains P: 0.005 wt% as needed. 0.5% by weight, based on the total amount of 0.05% by weight to 5% by weight of one or both of Sn and Ag, and 0.005% by weight to 1% by weight based on the total amount of one or two selected from the group consisting of Ti and R Above the above elements, the remainder includes Cu and inevitable impurities.
雖然防止水系統中的金屬製構件的孔蝕的技術正在持續開發，但實際情況是難以完全防止孔蝕。因此，於使用金屬材料的水系統中及早地感知局部腐蝕、即孔蝕的技術尤為重要。 Although the technique of preventing pitting corrosion of metal members in a water system is being continuously developed, it is difficult to completely prevent pitting corrosion. Therefore, it is particularly important to detect local corrosion, that is, pitting corrosion, early in a water system using a metal material.
先前，水系統中使用的金屬是藉由使該設備停止運轉、停水，而且，將金屬製構件的一部分取樣，測定樣本的孔蝕深度而推定孔蝕的產生。 Previously, the metal used in the water system was determined by stopping the operation of the equipment, stopping the water, and sampling a part of the metal member to measure the pitting depth of the sample to estimate the occurrence of pitting corrosion.
然而，先前的方法為使設備停止運轉且將金屬製構件的一部分取樣，而必須進行破壞，故而存在對工廠的作業造成影響之類的缺點。而且，亦存在於測定結果出來前，耗費極多的時間、勞力、及費用之類的缺陷。 However, the prior method is to stop the operation of the apparatus and to sample a part of the metal member, and it is necessary to perform the destruction, so that there is a disadvantage of affecting the operation of the factory. Moreover, there are also many defects such as time, labor, and expense before the measurement results come out.
因此，近年來，存在監控金屬製構件的孔蝕進展狀況的方法。例如，存在如下方法：藉由將包含與所監控的金屬製構件相同材質的測試件浸漬於水系統內，測定該測試件與比較電極之間的電位差的經時變化，而監控孔蝕狀況。若利用該方法，則不停止設備運轉且不破壞金屬製構件便可感知孔蝕。 Therefore, in recent years, there has been a method of monitoring the progress of pitting corrosion of a metal member. For example, there is a method of monitoring the pitting condition by measuring a time-dependent change in the potential difference between the test piece and the comparison electrode by immersing the test piece containing the same material as the metal member to be monitored in the water system. According to this method, pitting corrosion can be sensed without stopping the operation of the apparatus and without destroying the metal member.
作為更具體的示例，例如，於專利文獻2揭示有如下監控裝置，該監控裝置包括經由小孔而與水系統介質連通的儲液部、及以與該儲液部內的液體接觸的方式設置的金屬片，且藉由使金屬片的與上述儲液部內的液體接觸之面的面積大於上述小孔的開口面積而提高其精度。 As a more specific example, for example, Patent Document 2 discloses a monitoring device including a liquid storage portion that communicates with a water system medium via a small hole, and is provided in contact with a liquid in the liquid storage portion. The metal piece is improved in accuracy by making the area of the surface of the metal piece in contact with the liquid in the liquid storage portion larger than the opening area of the small hole.
而且，例如，於專利文獻3揭示有半截或大致半截管形 狀的測試件，該測試件是用於配管的孔蝕監控，包含與被監控配管相同或同質的材質，且可藉由使表面的氧化皮膜不均勻化，而高感度地反映被監控配管的腐蝕進展，從而確實地預知孔蝕的產生。 Moreover, for example, Patent Document 3 discloses that there is a half or a substantially half tube shape. The test piece is a pitting monitoring for piping, and includes the same or the same material as the pipe to be monitored, and can reflect the monitored pipe with high sensitivity by making the oxide film on the surface non-uniform. Corrosion progresses, thus reliably predicting the occurrence of pitting corrosion.
進而，例如於專利文獻4揭示有銅的孔蝕評價方法，該銅的孔蝕評價方法是將由腐蝕生成物S所覆蓋的包含銅片的陽極(anode)2、及接液面未被腐蝕生成物覆蓋的包含銅片的陰極(cathode)3在被電性絕緣的狀態下配置所得的評價電極1浸漬於水系統，測定於將該陽極2與該陰極3之間電性連接的電路中流通的電流，藉此，可準確地評價於與水系統接觸的銅中產生的孔蝕的進展狀況。 Further, for example, Patent Document 4 discloses a copper pitting evaluation method in which an anode 2 including a copper sheet covered by a corrosion product S and a liquid contact surface are not corroded. The cathode electrode 3 including the copper sheet is placed in a state of being electrically insulated, and the evaluation electrode 1 is immersed in a water system, and is measured and distributed in a circuit electrically connecting the anode 2 and the cathode 3. The current, by which, the progress of the pitting corrosion generated in the copper in contact with the water system can be accurately evaluated.
[先前技術文獻] [Previous Technical Literature]
[專利文獻] [Patent Literature]
[專利文獻1]日本專利特開平06-184669號公報 [Patent Document 1] Japanese Patent Laid-Open No. Hei 06-184669
[專利文獻2]日本專利特開平02-310452號公報 [Patent Document 2] Japanese Patent Laid-Open No. 02-310452
[專利文獻3]日本專利特開平05-322831號公報 [Patent Document 3] Japanese Patent Laid-Open No. Hei 05-322831
[專利文獻4]日本專利特開2011-214881號公報 [Patent Document 4] Japanese Patent Laid-Open Publication No. 2011-214881
對於如上所述地不停止設備運轉地監控金屬製構件的孔蝕的方法，迄今為止亦進行了用以提高其精度的各種設計。例如，於上述專利文獻3中，提出了如下方法，該方法是使成為陽極的測試件的表面的氧化皮膜不均勻化，成為容易產生孔蝕的狀態，藉此，高感度地感知腐蝕進展。 As for the method of monitoring the pitting corrosion of the metal member without stopping the operation of the apparatus as described above, various designs for improving the accuracy thereof have heretofore been performed. For example, in the above-mentioned Patent Document 3, a method is proposed in which the oxide film on the surface of the test piece which becomes the anode is made non-uniform, and the pitting corrosion is easily generated, whereby the progress of corrosion is perceived with high sensitivity.
此處，金屬製構件的孔蝕是金屬的溶解部分(陽極)與該溶解部分周邊的產生氧還原反應的部分(陰極)的電位差成為驅動力而進展。因此，認為自然電位上升，金屬的溶解部分(陽極)與該溶解部分周邊的產生氧還原反應的部分(陰極)的電位差變得更大，藉此，更助長孔蝕的產生。 Here, the pitting of the metal member is such that the potential difference between the dissolved portion (anode) of the metal and the portion (cathode) where the oxygen reduction reaction occurs around the dissolved portion becomes a driving force. Therefore, it is considered that the natural potential rises, and the potential difference between the dissolved portion (anode) of the metal and the portion (cathode) where the oxygen reduction reaction occurs around the dissolved portion becomes larger, thereby further contributing to the occurrence of pitting corrosion.
使自然電位上升的原因有次氯酸或次溴酸等氧化劑的過度添加。作為其他原因，作為某種微生物的代謝物而生成的過氧化物的影響亦較大。然而，於先前的孔蝕監控技術中，尚不存在可考慮到由微生物引起的自然電位上升導致孔蝕的產生，進行孔蝕監控的技術。 The reason for raising the natural potential is excessive addition of an oxidizing agent such as hypochlorous acid or hypobromous acid. For other reasons, the effect of peroxides produced as metabolites of certain microorganisms is also large. However, in the previous pitting monitoring technology, there is no technique for performing pitting corrosion monitoring in consideration of the occurrence of pitting corrosion caused by an increase in natural potential caused by microorganisms.
因此，本發明的主要目的在於提供亦可偵測微生物的影響的新穎的孔蝕監控技術。 Accordingly, it is a primary object of the present invention to provide novel pitting monitoring techniques that also detect the effects of microorganisms.
本申請案發明者等人對迄今為止的孔蝕監控技術為何無法偵測微生物的影響進行了努力研究。繼而，著重於在先前的孔蝕監控技術中，存在對於成為陽極的產生孔蝕的部分實施各種設計的技術，但對成為陰極的部分並未特別實施設計。其結果，發現於未實施任何設計的陰極中，即便掌握氧化劑等的過度添加，亦由於微生物或污垢的附著性差而難以偵測微生物的影響，從而完成了本發明。 The inventors of the present application have conducted an effort to study why the pitting monitoring technology to date has failed to detect the influence of microorganisms. Then, focusing on the prior art of the pitting monitoring technique, there are techniques for implementing various designs for the portion of the anode which is pitting, but the portion to be the cathode is not specifically designed. As a result, it has been found that in the cathode which has not been subjected to any design, even if excessive addition of an oxidizing agent or the like is grasped, it is difficult to detect the influence of microorganisms due to poor adhesion of microorganisms or dirt, and the present invention has been completed.
即，本發明首先提供一種孔蝕監控用測試件，其是用於評價水系統的金屬構件中產生的孔蝕的進展狀況的孔蝕監控的測試件，且包括：陰極部，包含與上述金屬構件相同的金屬材料，且至少於表面的一部分形成有凹凸；以及 陽極部，與上述陰極部電性絕緣，且包含上述金屬材料。 That is, the present invention first provides a test piece for pitting monitoring, which is a test piece for pitting monitoring for evaluating the progress of pitting corrosion generated in a metal member of a water system, and includes: a cathode portion including the metal described above a metal material having the same member, and at least a portion of the surface is formed with irregularities; The anode portion is electrically insulated from the cathode portion and includes the metal material.
本發明的孔蝕監控用測試件在成為陰極的部分形成有凹凸，故而微生物或污垢的附著性良好。 In the test piece for pitting monitoring of the present invention, irregularities are formed in a portion to be a cathode, and adhesion of microorganisms or dirt is good.
而且，本發明提供一種孔蝕監控用測試件，其是用於評價水系統的金屬構件中產生的孔蝕的進展狀況的孔蝕監控的測試件，且包括：第1陰極部，包含與上述金屬構件相同的金屬材料；陽極部，與上述第1陰極部電性絕緣，且包含上述金屬材料；以及第2陰極部，與上述第1陰極部電性短路，且包含上述金屬材料，於表面形成有凹凸。 Moreover, the present invention provides a test piece for pitting monitoring, which is a test piece for pitting monitoring for evaluating progress of pitting corrosion generated in a metal member of a water system, and includes: a first cathode portion including the above a metal material having the same metal member; an anode portion electrically insulated from the first cathode portion and including the metal material; and a second cathode portion electrically short-circuited with the first cathode portion and including the metal material on the surface There are irregularities formed.
用於本發明的孔蝕監控用測試件的金屬材料並無特別限定，但例如可使用銅或銅合金作為上述金屬材料。 The metal material used for the test piece for pitting monitoring of the present invention is not particularly limited, and for example, copper or a copper alloy can be used as the above metal material.
其次，本發明提供一種使用本發明的孔蝕監控測試件的孔蝕監控裝置。 Next, the present invention provides an aperture monitoring device using the pitting monitoring test piece of the present invention.
具體而言，提供一種孔蝕監控裝置，至少包括：本發明的孔蝕監控用測試件；以及電流測定部，測定將上述陰極部與上述陽極部之間電性連接的電路中所流通的電流；以及，提供一種孔蝕監控裝置，至少包括：本發明的孔蝕監控用測試件；以及極化電阻測定部，測定上述陽極部的極化電阻。 Specifically, a pitting monitoring device includes at least the pitting monitoring test piece of the present invention, and a current measuring unit that measures a current flowing in a circuit electrically connecting the cathode portion and the anode portion And a pitting monitoring device comprising at least: a pitting monitoring test piece of the present invention; and a polarization resistance measuring unit that measures a polarization resistance of the anode portion.
進而，本發明提供一種使用本發明的孔蝕監控用測試件的孔蝕監控方法。 Further, the present invention provides a pitting monitoring method using the test piece for pitting monitoring of the present invention.
具體而言，本發明提供一種孔蝕監控方法，其是評價水系統的金屬構件中產生的孔蝕的進展狀況的孔蝕監控方法，將本發明的孔蝕監控用測試件浸漬於水系統，藉由測定將上述陰極部與上述陽極部之間電性連接的電路中所流通的電流，而評價產生於上述金屬構件的孔蝕的進展狀況；以及提供一種孔蝕監控方法，其是評價水系統的金屬構件中產生的孔蝕的進展狀況的孔蝕監控方法，將本發明的孔蝕監控用測試件浸漬於水系統，藉由測定上述陽極部的極化電阻，而評價產生於上述金屬構件的孔蝕的進展狀況。 Specifically, the present invention provides a pitting monitoring method which is a pitting monitoring method for evaluating the progress of pitting corrosion generated in a metal member of a water system, and immersing the pitting monitoring test piece of the present invention in a water system, Evaluating the progress of pitting corrosion generated in the metal member by measuring an electric current flowing through a circuit electrically connecting the cathode portion and the anode portion; and providing a pitting monitoring method for evaluating water The pitting detection method for the progress of the pitting corrosion generated in the metal member of the system, the immersion monitoring test piece of the present invention is immersed in the water system, and the above-mentioned metal is evaluated by measuring the polarization resistance of the anode portion. The progress of the pitting corrosion of the component.
本發明的孔蝕監控方法可於以腐蝕生成物覆蓋上述陽極部，且上述陰極部的接液面未被腐蝕生成物覆蓋的狀態下進行評價。 In the pitting monitoring method of the present invention, the anode portion is covered with the corrosion product, and the liquid contact surface of the cathode portion is not covered by the corrosion product.
本發明的孔蝕監控用測試件可於陰極部中偵測微生物的影響，故而可更高感度地掌握陰極反應，其結果，可進行更高精度的孔蝕監控。 The test piece for pitting monitoring of the present invention can detect the influence of microorganisms in the cathode portion, so that the cathode reaction can be grasped with higher sensitivity, and as a result, more precise pitting monitoring can be performed.
1‧‧‧孔蝕監控用測試件 1‧‧‧Test pieces for pitting monitoring
10‧‧‧孔蝕監控裝置 10‧‧‧ Pitting monitoring device
11、110‧‧‧陰極部 11, 110‧‧‧ cathode
12‧‧‧陽極部 12‧‧‧Anode
13‧‧‧絕緣部 13‧‧‧Insulation
14‧‧‧陰極用導線 14‧‧‧Cathode wire
15‧‧‧陽極用導線 15‧‧‧Anode wire
101‧‧‧電流測定部 101‧‧‧ Current Measurement Department
102‧‧‧極化電阻測定部 102‧‧‧Polarization Resistance Measurement Department
103‧‧‧對照電極 103‧‧‧Control electrode
104‧‧‧相對電極 104‧‧‧relative electrode
105‧‧‧恆電位/恆電流儀 105‧‧‧potentiostatic/galvanostat
111‧‧‧小孔 111‧‧‧Small hole
112‧‧‧儲液部 112‧‧‧Liquid Storage Department
S‧‧‧腐蝕生成物 S‧‧‧Corrosion products
W‧‧‧評價水系統 W‧‧‧Evaluation of water systems
X‧‧‧虛線圓 X‧‧‧dred circle
圖1A及圖1B是示意性地表示本發明的孔蝕監控用測試件的第1實施方式的示意圖，圖1A是第1實施方式的孔蝕監控用測試件的正面示意圖，圖1B是圖1A的I-I'箭線示意剖面圖。 1A and 1B are schematic views showing a first embodiment of a test piece for pitting monitoring according to the present invention, and Fig. 1A is a front view showing a test piece for pitting monitoring according to the first embodiment, and Fig. 1B is a view of Fig. 1A. The I-I' arrow is a schematic sectional view.
圖2是將圖1B的虛線圓X部分放大所得的示意剖面圖。 Fig. 2 is a schematic cross-sectional view showing an enlarged portion of a broken line circle X of Fig. 1B.
圖3是示意性地表示本發明的孔蝕監控用測試件的第2實施方式的示意剖面圖。 Fig. 3 is a schematic cross-sectional view schematically showing a second embodiment of the test piece for monitoring the pitting corrosion of the present invention.
圖4是示意性地表示本發明的孔蝕監控用測試件的第3實施方式的示意剖面圖。 Fig. 4 is a schematic cross-sectional view schematically showing a third embodiment of the test piece for pitting corrosion monitoring of the present invention.
圖5是示意性地表示本發明的孔蝕監控裝置的第1實施方式的示意圖。 Fig. 5 is a schematic view schematically showing a first embodiment of the pitting monitoring device of the present invention.
圖6是示意性地表示本發明的孔蝕監控裝置的第2實施方式的示意圖。 Fig. 6 is a schematic view schematically showing a second embodiment of the pitting monitoring device of the present invention.
圖7是用以說明本發明的孔蝕監控方法的示意圖。 Fig. 7 is a schematic view for explaining the pitting monitoring method of the present invention.
以下，一面參照圖式，一面對用以實施本發明的較佳形態進行詳細說明。此外，以下說明的實施方式是表示本發明的代表性實施方式的一例，而並非藉此狹義地解釋本發明的範圍。 Hereinafter, the preferred embodiments for carrying out the invention will be described in detail with reference to the drawings. Further, the embodiments described below are examples of representative embodiments of the present invention, and the scope of the present invention is not construed in a narrow sense.
<1.孔蝕監控用測試件1> <1. Test piece for pitting monitoring 1>
本發明的孔蝕監控用測試件1是用於評價水系統的金屬構件中產生的孔蝕的進展狀況的孔蝕監控的測試件，大體而言，至少包括陰極部11、陽極部12、及絕緣部13。而且，亦可視需要更包括陰極用導線14、陽極用導線15等。以下，一面例示各實施方式，一面對各部分進行詳細說明。 The test piece 1 for pitting monitoring of the present invention is a test piece for pitting monitoring for evaluating the progress of pitting corrosion generated in a metal member of a water system, and generally includes at least a cathode portion 11, an anode portion 12, and Insulation portion 13. Further, the cathode lead wire 14, the anode lead wire 15, and the like may be further included as needed. Hereinafter, each embodiment will be exemplified, and each part will be described in detail.
(1)第1實施方式 (1) First embodiment
圖1A及圖1B是示意性地表示本發明的孔蝕監控用測試件1的第1實施方式的示意圖。圖1A是第1實施方式的孔蝕監控用測試件1的正面示意圖，圖1B是圖1A的I-I'箭線示意剖面圖。 第1實施方式的孔蝕監控用測試件1是以陰極部11與陽極部12由絕緣部13電性絕緣的狀態配置，且於陰極部11及陽極部12分別連接有陰極用導線14、陽極用導線15。 1A and 1B are schematic views schematically showing a first embodiment of the test piece 1 for pitting corrosion monitoring of the present invention. Fig. 1A is a front elevational view showing a test piece 1 for pitting corrosion monitoring according to a first embodiment, and Fig. 1B is a schematic cross-sectional view taken along line I-I' of Fig. 1A. In the test piece 1 for the pitting monitoring according to the first embodiment, the cathode portion 11 and the anode portion 12 are electrically insulated from each other by the insulating portion 13, and the cathode lead 14 and the anode are connected to the cathode portion 11 and the anode portion 12, respectively. Use wire 15.
第1實施方式的孔蝕監控用測試件1中，陰極部11與陽極部12的接液面成為同一平面狀，且陰極部11及陽極部12為除接液面以外均埋設於絕緣部13中的狀態。 In the test piece 1 for pitting monitoring according to the first embodiment, the liquid contact surfaces of the cathode portion 11 and the anode portion 12 are flush with each other, and the cathode portion 11 and the anode portion 12 are buried in the insulating portion 13 except for the liquid contact surface. The state in .
陰極部11及陽極部12包含與評價孔蝕的進展狀況的對象金屬構件相同的金屬材料。具體的金屬材料的種類並無限定，可自由地選擇使用於水系統中可產生孔蝕的金屬材料。例如，可列舉銅、銅合金、鋼鐵、不鏽鋼等。 The cathode portion 11 and the anode portion 12 contain the same metal material as the target metal member for evaluating the progress of the pitting corrosion. The type of the specific metal material is not limited, and the metal material which can be used for pitting corrosion in the water system can be freely selected. For example, copper, a copper alloy, steel, stainless steel, etc. are mentioned.
陰極部11及陽極部12的形態只要無損本發明的效果則亦無特別限定，可自由設計。作為陽極部12，例如可使用金屬製線材等。而且，作為陰極部11，例如可使用金屬製板、金屬製管等。 The form of the cathode portion 11 and the anode portion 12 is not particularly limited as long as the effects of the present invention are not impaired, and can be freely designed. As the anode portion 12, for example, a metal wire or the like can be used. Further, as the cathode portion 11, for example, a metal plate, a metal pipe, or the like can be used.
陽極部12的接液面的面積亦無特別限定，只要能評價孔蝕的進展，則可自由設計。本發明尤其而言，較佳為將陽極部12的接液面的面積設計為10mm2以下，更佳為設計為1mm2以下。 The area of the liquid contact surface of the anode portion 12 is also not particularly limited, and can be freely designed as long as the progress of the pitting corrosion can be evaluated. In particular, in the present invention, the area of the liquid contact surface of the anode portion 12 is preferably 10 mm 2 or less, and more preferably 1 mm 2 or less.
陰極部11的接液面的面積亦無特別限定，只要大於陽極部12的接液面的面積，則可自由設計。本發明尤其而言，較佳為將陰極部11的接液面的面積設計為陽極部12的接液面的面積的10倍以上，更佳為設計為100倍以上，進而較佳為設計為1000倍以上。 The area of the liquid contact surface of the cathode portion 11 is also not particularly limited, and can be freely designed as long as it is larger than the area of the liquid contact surface of the anode portion 12. In particular, in the present invention, it is preferable that the area of the liquid contact surface of the cathode portion 11 is designed to be 10 times or more the area of the liquid contact surface of the anode portion 12, more preferably 100 times or more, and further preferably designed as More than 1000 times.
本發明的孔蝕監控用測試件1是如將圖1B的虛線圓X部分放大所得的示意剖面圖即圖2所示，特徵為於陰極部11的表 面形成有凹凸。可藉由在陰極部11的表面形成凹凸，而於陰極部靈敏地掌握起因於微生物的電位上升。其結果，可進行更高精度的孔蝕監控。 The test piece 1 for pitting monitoring according to the present invention is a schematic cross-sectional view obtained by enlarging a portion of a broken line circle X of Fig. 1B, that is, Fig. 2, and is characterized by a table at the cathode portion 11. The surface is formed with irregularities. By forming irregularities on the surface of the cathode portion 11, it is possible to sensitively grasp the increase in potential due to microorganisms in the cathode portion. As a result, more accurate pitting monitoring can be performed.
形成絕緣部13的材料只要能將陰極部11與陽極部12電性絕緣則無特別限定，可自由地選擇使用公知的絕緣材料。例如，可列舉環氧樹脂、氟樹脂等樹脂；矽酮橡膠(silicone rubber)等。 The material forming the insulating portion 13 is not particularly limited as long as it can electrically insulate the cathode portion 11 from the anode portion 12, and a known insulating material can be freely selected and used. For example, a resin such as an epoxy resin or a fluororesin; a silicone rubber or the like can be given.
陰極用導線14及陽極用導線15在本發明的孔蝕監控用測試件1中並非為必須的構成。例如，亦可藉由將陰極部11及陽極部12設計為可連接來自外部的導線，而使用來自下述電流測定部或極化電阻測定部的導線、或已有的可拆卸的導線等。 The cathode lead 14 and the anode lead 15 are not essential in the pitting monitoring test piece 1 of the present invention. For example, the cathode portion 11 and the anode portion 12 may be designed to be connected to a lead wire from the outside, and a lead wire from a current measuring portion or a polarization resistance measuring portion, or a conventional detachable lead wire or the like may be used.
於包含陰極用導線14及陽極用導線15的情況下，形成該等的材料只要為具有導電性的材料則無特別限定，可自由地選擇使用公知的導電性材料。例如可列舉銅、鋁、鋼等。此外，陰極用導線14及陽極用導線15是浸漬於水系統中使用，故而必須由絕緣材料被覆。 In the case of including the cathode lead wire 14 and the anode lead wire 15, the material to be formed is not particularly limited as long as it is a conductive material, and a known conductive material can be freely selected and used. For example, copper, aluminum, steel, etc. are mentioned. Further, since the cathode lead wire 14 and the anode lead wire 15 are used by being immersed in a water system, they must be covered with an insulating material.
(2)第2實施方式 (2) Second embodiment
圖3是示意性地表示本發明的孔蝕監控用測試件1的第2實施方式的示意剖面圖。本發明的孔蝕監控用測試件1的第2實施方式的特徵在於具有與第1陰極部11電性短路的第2陰極部110。 Fig. 3 is a schematic cross-sectional view schematically showing a second embodiment of the pitting monitoring test piece 1 of the present invention. The second embodiment of the pitting monitoring test piece 1 of the present invention is characterized in that it has a second cathode portion 110 that is electrically short-circuited with the first cathode portion 11.
第2陰極部110包含與評價孔蝕的進展狀況的對象金屬構件相同的金屬材料。具體的金屬材料的種類並無限定，可自由地選擇使用可於水系統中產生孔蝕的金屬材料。例如，可列舉銅、 銅合金、鋼鐵、不鏽鋼等。 The second cathode portion 110 includes the same metal material as the target metal member that evaluates the progress of the pitting corrosion. The type of the specific metal material is not limited, and a metal material which can cause pitting corrosion in the water system can be freely selected. For example, copper, Copper alloy, steel, stainless steel, etc.
第2陰極部110的形態只要無損本發明的效果則亦無特別限定，可自由設計。例如，可使用金屬製片、金屬製管等。 The form of the second cathode portion 110 is not particularly limited as long as the effects of the present invention are not impaired, and can be freely designed. For example, a metal sheet, a metal tube, or the like can be used.
特徵為於第2陰極部110的表面形成有凹凸。若藉由在第2陰極部110的表面形成凹凸而於第2陰極部110中靈敏地掌握起因於微生物的電位上升，則第1陰極部11的電位亦作為混合電位上升。其結果，可進行更高精度的孔蝕監控。 The feature is that irregularities are formed on the surface of the second cathode portion 110. When the second cathode portion 110 is sensitively grasped by the potential increase of the microorganisms by forming irregularities on the surface of the second cathode portion 110, the potential of the first cathode portion 11 also rises as a mixed potential. As a result, more accurate pitting monitoring can be performed.
可藉由如此般除設置第1陰極部11以外，亦設置第2陰極部110作為陰極部，而容易地更換靈敏地掌握起因於微生物的電位上升的第2陰極部110。而且，亦可容易地增減陰極部的接液面積。 In addition to the first cathode portion 11, the second cathode portion 110 is provided as a cathode portion, and the second cathode portion 110 which is caused by the increase in the potential of the microorganism can be easily changed. Moreover, it is also possible to easily increase or decrease the liquid contact area of the cathode portion.
此外，於第2實施方式的孔蝕監控用測試件1中，第2陰極部110以外的構成與上述第1實施方式相同，但第2實施方式亦可於第1陰極部11的表面不形成凹凸。當然，即便於第2實施方式中，亦可自由地亦於第1陰極部11的表面形成凹凸。 In the test piece 1 for the pitting monitoring according to the second embodiment, the configuration other than the second cathode portion 110 is the same as that of the first embodiment, but the second embodiment may not be formed on the surface of the first cathode portion 11. Bump. Of course, even in the second embodiment, irregularities can be formed on the surface of the first cathode portion 11 freely.
(3)第3實施方式 (3) Third embodiment
圖4是示意性地表示本發明的孔蝕監控用測試件的第3實施方式的示意剖面圖。第3實施方式的孔蝕監控用測試件1的特徵為於陰極部11包括小孔111、及經由該小孔111而與水系統連通的儲液部112。 Fig. 4 is a schematic cross-sectional view schematically showing a third embodiment of the test piece for pitting corrosion monitoring of the present invention. The pitting monitoring test piece 1 of the third embodiment is characterized in that the cathode portion 11 includes a small hole 111 and a liquid storage portion 112 that communicates with the water system via the small hole 111.
而且，將陽極部12的與儲液部112內的液體接觸的接液面設計為大於小孔111的開口面積。可藉由以此方式設計，而於儲液部112內模擬地製作使局部腐蝕增強的狀態。該第3實施方式是尤其適於監控軟鋼孔蝕的構成。 Further, the liquid contact surface of the anode portion 12 that is in contact with the liquid in the liquid storage portion 112 is designed to be larger than the opening area of the small hole 111. By designing in this manner, a state in which local corrosion is enhanced can be artificially produced in the liquid storage portion 112. This third embodiment is particularly suitable for monitoring the pitting corrosion of soft steel.
此外，第3實施方式的孔蝕監控用測試件1可將除小孔111及儲液部112以外的構成形成為與上述第1實施方式相同。 In the test piece 1 for the pitting monitoring according to the third embodiment, the configuration other than the small hole 111 and the liquid storage portion 112 can be formed in the same manner as in the first embodiment.
<2.孔蝕監控裝置10及孔蝕監控方法> <2. Pitting monitoring device 10 and pitting monitoring method>
本發明的孔蝕監控裝置10是使用本發明的孔蝕監控用測試件1進行孔蝕監控的裝置。具體而言，本發明的孔蝕監控裝置10是至少包括上述本發明的孔蝕監控用測試件1、電流測定部101及/或極化電阻測定部102的裝置。以下，一面例示各實施方式一面對各部分進行詳細說明。此外，由於孔蝕監控用測試件1與上述相同，故而此處省略說明。 The pitting monitoring device 10 of the present invention is a device for performing pitting monitoring using the pitting monitoring test piece 1 of the present invention. Specifically, the pitting monitoring device 10 of the present invention is a device including at least the puncture monitoring test piece 1, the current measuring unit 101, and/or the polarization resistance measuring unit 102 of the present invention. Hereinafter, each embodiment will be described in detail with reference to each embodiment. Further, since the test piece 1 for the pitting monitoring is the same as described above, the description thereof is omitted here.
(1)第1實施方式 (1) First embodiment
圖5是示意性地表示本發明的孔蝕監控裝置10的第1實施方式的示意圖。第1實施方式的孔蝕監控裝置10具有電流測定部101。此外，圖中符號W表示評價水系統。 Fig. 5 is a schematic view schematically showing a first embodiment of the pitting monitoring device 10 of the present invention. The pitting monitoring device 10 of the first embodiment includes a current measuring unit 101. Further, the symbol W in the figure indicates the evaluation water system.
第1實施方式的孔蝕監控裝置10是於陰極部11與陽極部12間形成電性連接的電路，且於電流測定部101中，伴隨孔蝕的進展，測定在電路中流通的電流(短路電流)。 The pitting monitoring device 10 of the first embodiment is a circuit that is electrically connected between the cathode portion 11 and the anode portion 12, and the current measuring unit 101 measures the current flowing through the circuit in accordance with the progress of the pitting corrosion (short circuit). Current).
作為電流測定部101，只要能測定短路電流，則可使用公知的電流計，但例如可藉由將無電阻電流計串列連接於上述電路而進行測定。由於陰極部11與陽極部12間的電流值對應於孔蝕的進展速度，故而，可根據短路電流的行為，評價孔蝕的進展狀況。 As the current measuring unit 101, a known galvanometer can be used as long as it can measure the short-circuit current. For example, the current measuring unit 101 can be connected by connecting a non-resistive galvanometer to the above-described circuit. Since the current value between the cathode portion 11 and the anode portion 12 corresponds to the progress speed of the pitting corrosion, the progress of the pitting corrosion can be evaluated based on the behavior of the short-circuit current.
(2)第2實施方式 (2) Second embodiment
圖6是示意性地表示本發明的孔蝕監控裝置10的第2實施方式的示意圖。第2實施方式的孔蝕監控裝置10具有極化電 阻測定部102。 Fig. 6 is a schematic view schematically showing a second embodiment of the pitting monitoring device 10 of the present invention. The pitting monitoring device 10 of the second embodiment has polarized electricity The resistance measuring unit 102.
第2實施方式的孔蝕監控裝置10是於陰極部11與陽極部12間形成電性連接的電路，且於每一任意期間在將上述電路的電性連接解除的狀態下，利用極化電阻測定部102測定陽極部12的極化電阻。極化電阻具有與腐蝕速度為反比例的關係，故而，可根據陽極部12的極化電阻的變化，測定陽極部12的腐蝕速度的變化，從而可評價孔蝕的進展狀況。 The pitting monitoring device 10 according to the second embodiment is a circuit that electrically connects between the cathode portion 11 and the anode portion 12, and uses a polarization resistor in a state where the electrical connection of the circuit is released in every arbitrary period. The measuring unit 102 measures the polarization resistance of the anode portion 12. Since the polarization resistance has an inverse relationship with the corrosion rate, the change in the corrosion rate of the anode portion 12 can be measured based on the change in the polarization resistance of the anode portion 12, and the progress of the pitting corrosion can be evaluated.
極化電阻例如可依據JIS K0100「工業用水腐蝕性試驗方法」中記載的方法，將相對電極104浸漬於水系統，將陽極部12作為試樣電極進行測定。而且，亦可測定陰極部11的極化電阻，且與陽極部12的極化電阻進行比較。 The polarization resistance can be measured, for example, by immersing the counter electrode 104 in a water system and using the anode portion 12 as a sample electrode in accordance with the method described in JIS K0100 "Industrial Water Corrosion Test Method". Further, the polarization resistance of the cathode portion 11 can be measured and compared with the polarization resistance of the anode portion 12.
進而，將對照電極103浸漬於評價水系統W，雖未圖示，但亦可結合地進行使陰極部11及陽極部12短路的狀態下的電位測定。 Further, the control electrode 103 is immersed in the evaluation water system W, and although not shown, the potential in the state in which the cathode portion 11 and the anode portion 12 are short-circuited may be measured in combination.
另外，雖未圖示，但亦可一面藉由設為兼具上述第1實施方式的電流測定部101及第2實施方式的極化電阻測定部102的裝置，而持續地實施短路電流的測定，一面於每一任意期間結合地進行上述極化電阻的測定。亦可藉由上述短路電流測定或極化電阻測定結果，進而亦結合地進行使陰極部11及陽極部12短路的狀態下的電位測定，而進行孔蝕進展的要因考察。 Further, although not shown, the short-circuit current can be continuously measured by using the current measuring unit 101 of the first embodiment and the polarization resistance measuring unit 102 of the second embodiment. The above polarization resistance is measured in combination with each of the arbitrary periods. It is also possible to measure the potential in the state in which the cathode portion 11 and the anode portion 12 are short-circuited in combination with the short-circuit current measurement or the polarization resistance measurement result, and to examine the cause of the pitting progress.
本發明的孔蝕監控方法中，較佳為在以腐蝕生成物覆蓋上述陽極部12，且上述陰極部11的接液面未被腐蝕生成物覆蓋的狀態下進行評價。可藉由在此種狀態下進行評價，而高精度地評價例如銅或銅合金的孔蝕狀況。銅是伴隨腐蝕的交換電流密度較 低的耐腐蝕性材料，且陽極部12中的腐蝕進展迅速受到抑制，故而難以評價孔蝕的進展狀況。然而，亦可藉由使用被腐蝕生成物覆蓋的狀態的陽極部12、及模擬未被腐蝕生成物覆蓋的健全面的陰極部11，而評價先前技術較為困難的銅的孔蝕進展狀況。 In the pitting monitoring method of the present invention, it is preferable that the anode portion 12 is covered with a corrosion product, and the liquid contact surface of the cathode portion 11 is not covered by the corrosion product. The pitting condition of, for example, copper or a copper alloy can be evaluated with high precision by performing evaluation in such a state. Copper is the exchange current density associated with corrosion Since the corrosion resistance of the material in the anode portion 12 is rapidly suppressed, the progress of the pitting corrosion is difficult to evaluate. However, it is also possible to evaluate the progress of pitting corrosion of copper which is difficult in the prior art by using the anode portion 12 in a state covered with a corrosion product and the cathode portion 11 simulating a sound surface which is not covered by the corrosion product.
作為使陽極部12產生腐蝕生成物的方法，例如圖7所示，可藉由將本發明的孔蝕監控用測試件1浸漬於水中，且對陽極部12通電的方法進行。更具體而言，可藉由如下方法而僅使陽極部12生成腐蝕生成物S，上述方法是將孔蝕監控用測試件1及對照電極103浸漬於水中，將陽極部12作為試樣電極，將陰極部11作為相對電極，使用恆電位/恆電流儀(potentiogalvanostat)105等，一面利用攪拌器(stirrer)(未圖示)等攪拌一面以恆定時間以規定的電流進行通電。 As a method of causing the anode portion 12 to generate a corrosion product, for example, as shown in FIG. 7, the test piece 1 for pitting corrosion monitoring of the present invention can be immersed in water and the anode portion 12 can be energized. More specifically, the corrosion product S can be formed only in the anode portion 12 by the method of immersing the pitting monitoring test piece 1 and the control electrode 103 in water, and using the anode portion 12 as a sample electrode. The cathode portion 11 is used as a counter electrode, and a potentiogalvanostat 105 or the like is used to conduct electricity at a predetermined current for a constant time while stirring using a stirrer (not shown) or the like.
此時，對陽極部12通電的電流值、通電時間，只要能以腐蝕生成物S覆蓋陽極部12則無特別限定，可自由設定。由於腐蝕生成物S的生成亦因水質條件而受到影響，因此，較佳為根據水質等適當調整電流值、通電時間等。 In this case, the current value and the energization time for energizing the anode portion 12 are not particularly limited as long as the anode portion 12 can be covered with the corrosion product S, and can be freely set. Since the generation of the corrosion product S is also affected by the water quality conditions, it is preferable to appropriately adjust the current value, the energization time, and the like according to the water quality or the like.
若使用本發明的孔蝕監控用測試件、孔蝕監控裝置、孔蝕監控方法，則可迅速掌握於水系統中使用金屬材料的配管或熱交換器等中所產生的孔蝕。因此，可將設備的作業停止等意外事態的產生防患於未然。 When the pitting monitoring test piece, the pitting monitoring device, and the pitting monitoring method of the present invention are used, it is possible to quickly grasp the pitting corrosion generated in a pipe or a heat exchanger using a metal material in a water system. Therefore, it is possible to prevent the occurrence of an unexpected situation such as the stop of the operation of the device.
而且，若使用本發明的孔蝕監控用測試件、孔蝕監控裝置、孔蝕監控方法，則亦可評價水處理藥劑對孔蝕的抑制效果等。 Further, when the pitting monitoring test piece, the pitting monitoring device, and the pitting monitoring method of the present invention are used, the effect of suppressing pitting corrosion by the water treatment agent can be evaluated.
1‧‧‧孔蝕監控用測試件 1‧‧‧Test pieces for pitting monitoring
11‧‧‧陰極部 11‧‧‧ Cathode
12‧‧‧陽極部 12‧‧‧Anode
13‧‧‧絕緣部 13‧‧‧Insulation
14‧‧‧陰極用導線 14‧‧‧Cathode wire
15‧‧‧陽極用導線 15‧‧‧Anode wire
X‧‧‧虛線圓 X‧‧‧dred circle
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| JP2013008650A JP5626380B2 (en) | 2013-01-21 | 2013-01-21 | Pitting corrosion monitoring test piece, pitting corrosion monitoring device, and pitting corrosion monitoring method |
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| JP6623329B2 (en) * | 2015-07-01 | 2019-12-25 | 株式会社三井Ｅ＆Ｓマシナリー | Corrosion sensor |
| JP6623326B2 (en) * | 2015-07-01 | 2019-12-25 | 株式会社三井Ｅ＆Ｓマシナリー | Corrosion sensor |
| WO2019082265A1 (en) * | 2017-10-24 | 2019-05-02 | 都市拡業株式会社 | Comparative experiment device and comparative experiment method |
| US11029244B1 (en) * | 2017-10-26 | 2021-06-08 | The Government Of The United States Of America, As Represented By The Secretary Of The Navy | Electrochemical ZRA test cells for determination of galvanic corrosion rates in atmospheric environments |
| CN108680494B (en) * | 2018-06-28 | 2024-03-26 | 天津市澳玛科技开发有限公司 | Method and device for detecting corrosion resistance of food-grade tinplate inner coating |
| CN108760837A (en) * | 2018-07-20 | 2018-11-06 | 中国石油化工股份有限公司 | A kind of orifice-plate type oilfield sewage fouling on-line monitoring probe |
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| JP2855654B2 (en) * | 1989-05-25 | 1999-02-10 | 栗田工業株式会社 | How to monitor local corrosion |
| JP2536364B2 (en) * | 1992-05-26 | 1996-09-18 | 栗田工業株式会社 | Test piece |
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