JPH0318503Y2 - - Google Patents
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- Publication number
- JPH0318503Y2 JPH0318503Y2 JP9431485U JP9431485U JPH0318503Y2 JP H0318503 Y2 JPH0318503 Y2 JP H0318503Y2 JP 9431485 U JP9431485 U JP 9431485U JP 9431485 U JP9431485 U JP 9431485U JP H0318503 Y2 JPH0318503 Y2 JP H0318503Y2
- Authority
- JP
- Japan
- Prior art keywords
- current
- transistor
- corrosion
- pipe
- constant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000005260 corrosion Methods 0.000 claims description 33
- 230000007797 corrosion Effects 0.000 claims description 29
- 238000004210 cathodic protection Methods 0.000 claims description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 34
- 239000011777 magnesium Substances 0.000 description 18
- 229910052742 iron Inorganic materials 0.000 description 17
- 238000010586 diagram Methods 0.000 description 8
- 230000007423 decrease Effects 0.000 description 6
- 229910052749 magnesium Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000005536 corrosion prevention Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000028161 membrane depolarization Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- -1 zinc and magnesium Chemical class 0.000 description 1
Landscapes
- Prevention Of Electric Corrosion (AREA)
Description
【考案の詳細な説明】
〔産業上の利用分野〕
この考案は、一般のガス管、水道管など埋設鉄
管の電気防食用として広く利用されている外部電
源式による電食防止技術の改善に関するものであ
り、特許登録No.764101および特願昭59−089945に
係わり、その応用によるものである。[Detailed description of the invention] [Field of industrial application] This invention relates to the improvement of an externally powered electrolytic corrosion prevention technology that is widely used for the electrolytic corrosion protection of buried iron pipes such as general gas pipes and water pipes. This is related to Patent Registration No. 764101 and Japanese Patent Application No. 59-089945, and is based on its application.
従来より多く使用されている電気防食用外部電
源式は、電気軌条の近傍に埋設されている防食対
象管路に、外部電源の極を接続し、極を通
電々極に接続したものが使用される。
The external power supply type for cathodic protection, which has been widely used in the past, connects the poles of the external power supply to the pipeline to be protected against corrosion, which is buried near the electric rail, and connects the poles to the current-carrying terminals. Ru.
上記の従来技術において問題となる埋設管など
に発生する電食に就て第２図を用いて説明する。
The electrolytic corrosion that occurs in buried pipes and the like, which is a problem in the above-mentioned conventional technology, will be explained using FIG. 2.
電気軌条Ｒの近傍に配設されている埋設鉄管
P1に、電気軌条Ｒより迷走電流（漏洩電流）が
矢印方向で流入し、この埋設鉄管P1の末端部か
ら外方の矢印方向に電流が流出する。この流出に
伴つて、その部分で金属をイオン化し、酸化し電
食が発生する。 Buried iron pipes installed near electric rail R
Stray current (leakage current) flows into P1 from the electric rail R in the direction of the arrow, and current flows outward from the end of the buried iron pipe P1 in the direction of the arrow. With this outflow, metals in that area are ionized and oxidized, causing electrolytic corrosion.
このような電食を防止するために、上述のよう
な外部電源方式が使用され、之を第３図によつて
説明する。 In order to prevent such electrolytic corrosion, an external power supply system as described above is used, which will be explained with reference to FIG.
先ず、電気軌条Ｒより迷走電流が矢印の方向に
流れて埋設鉄管P1に流入すると共に、外部電源
DC1の極に接続されている通電々極A1から電
流が矢印方向に流出して埋設鉄管P1に流入する
ことにより、流入が重なつて埋設鉄管P1は過防
食となる。 First, a stray current flows from the electric rail R in the direction of the arrow and flows into the buried iron pipe P1 , and the external power supply
When the current flows out in the direction of the arrow from the current-carrying electrode A 1 connected to the pole of DC 1 and flows into the buried iron pipe P 1 , the inflows overlap and the buried iron pipe P 1 becomes over-corrosion-protected.
このような埋設管における過防食は、管体被覆
の剥離を起すのみでなく、他の埋設管に対して干
渉を誘発するなど問題点が多い。 Excessive corrosion protection in such buried pipes not only causes peeling of the pipe coating, but also causes many problems, such as inducing interference with other buried pipes.
前記の問題点を解決するために、本考案者等
は、従来技術を改善した装置を考案した。以下、
本考案の実施例に対応する第１図を用いて説明す
る。
In order to solve the above-mentioned problems, the present inventors have devised a device that improves on the prior art. below,
This will be explained using FIG. 1 which corresponds to an embodiment of the present invention.
防食対象管路Ｐと、通電々極Ａ間に、この方向
で定電圧直流源DCを接続し、定電圧直流電源DC
と、通電々極Ａとの間に第１トランジスターとし
て、NPN型トランジスターTR1のコレクターC1
と、エミツターE1とをこの順に接続し、更に防
食対象管路Ｐと、流電陽極Mg間に、第２のトラ
ンジスターとしてPNP型トランジスターTR2の
エミツターE2、ベースB2の順に接続し、且つト
ランジスターTR2のコレクターC2を、第１のト
ランジスターTR1のベースB1に接続した回路構
成からなる装置である。 Connect a constant voltage DC source DC in this direction between the pipe P to be protected against corrosion and the energized polarity A, and connect the constant voltage DC power source DC
and the collector C 1 of the NPN transistor TR 1 as the first transistor between the current-carrying pole A and the current carrying pole A.
and the emitter E 1 are connected in this order, and the emitter E 2 and the base B 2 of the PNP transistor TR 2 are connected in this order as a second transistor between the pipe P to be protected against corrosion and the current anode Mg . In addition, this device has a circuit configuration in which the collector C 2 of the transistor TR 2 is connected to the base B 1 of the first transistor TR 1.
上述の本考案の装置に基づいて作用を、実施例
を示す第１図によつて説明する。
The operation based on the above-mentioned apparatus of the present invention will be explained with reference to FIG. 1 showing an embodiment.
防食対象管路Ｐと、流電陽極Mgに対して、管
対地電位が、流電陽極Mgの電位より高い場合
は、防食対象管路Ｐより流電陽極Mgにベース電
流即ち流電陽極電流が流れる。然も防食対象管路
Ｐと、通電々極Ａ間には、定電圧直流電源DCが
印加されているので、トランジスターTR1に於て
は、トランジスターTR2のコレクターC2電流即
ち之に接続しているトランジスターTR1のベース
B1電流に応じて、トランジスターTR1のコレク
ターC1電流が、防食対象管路Ｐと、通電々極Ａ
間に流れる。 If the pipe-to-ground potential is higher than the potential of the galvanic anode Mg with respect to the pipe P to be protected against corrosion and the galvanic anode Mg, the base current, that is, the galvanic anode current, flows from the pipe P to be protected against corrosion to the galvanic anode Mg. flows. However, since a constant voltage DC power supply DC is applied between the pipe P to be protected against corrosion and the current-carrying terminal A, the transistor TR 1 is connected to the collector C 2 current of the transistor TR 2 . The base of the transistor TR 1
According to the B 1 current, the collector C 1 current of the transistor TR 1 flows between the pipe P to be protected against corrosion and the current carrying polarity A.
flowing between.
このようにして、例えば防食対象管路Ｐと、流
電陽極Mg間の電圧が減少すれば、流電陽極Mg
電流が減少し、従つてトランジスターTR2のコレ
クター電流即ちトランジスターTR1のベース電流
が減少し、従つてトランジスターTR1のコレクタ
ーC1電流は減少する。 In this way, for example, if the voltage between the pipe P to be protected against corrosion and the galvanic anode Mg decreases, the galvanic anode Mg
The current decreases and thus the collector current of the transistor TR 2 and hence the base current of the transistor TR 1 decreases and thus the collector C 1 current of the transistor TR 1 decreases.
また、流電陽極Mgの電圧が、防食対象管路Ｐ
の電圧より高いような、上記と逆のような場合
は、トランジスターTR2のエミツタE2と、ベー
スB2に対して逆電圧が作用することになるので、
トランジスターTR2としては、作動せず、従つて
上記のようなトランジスターTR1のベースB1電
流は流れず、従つてコレクターC1電流は流れな
い。 In addition, the voltage of the galvanic anode Mg is
In the opposite case to the above , where the voltage is higher than
As a transistor TR 2 , it is not activated, so the base B 1 current of the transistor TR 1 as described above does not flow, and therefore the collector C 1 current does not flow.
なお、流電陽極Mgを、防食対象管路Ｐの近傍
に設置し、而も防食対象管路Ｐの対地電位が、流
電陽極Mgの電位に近接している場合には、前述
のようにトランジスターTR2のコレクターC2電
流の減少に伴い、トランジスターTR1のベース
B1電流の減少からして防食対象管路Ｐの電位は、
流電陽極Mgの電位と近似した値に制御される。 In addition, when the galvanic anode Mg is installed near the pipe P to be protected against corrosion, and the ground potential of the pipe P to be corrosion protected is close to the potential of the galvanic anode Mg, as described above, With the decrease of the collector C 2 current of the transistor TR 2 , the base of the transistor TR 1
B1 From the decrease in current, the potential of the pipe P to be protected against corrosion is
It is controlled to a value close to the potential of the galvanic anode Mg.
この場合、電源DC電圧が一定であつても、ト
ランジスターTR1のコレクターC1電流即ち防食
対象管路Ｐと、通電々極Ａとの間の防食通電々流
は、防食対象管路Ｐと、流電陽極Mg間の電位状
況に応じて通電し、防食対象管路Ｐの電位は、流
電陽極Mgの電位に定電位制御されるものであ
る。 In this case, even if the power supply DC voltage is constant, the current flowing through the collector C1 of the transistor TR1 , that is, the corrosion protection current between the pipe P to be protected against corrosion and the current-carrying polarity A, is Electricity is applied according to the potential situation between the galvanic anodes Mg, and the potential of the pipeline P to be protected against corrosion is controlled to be constant at the potential of the galvanic anodes Mg.
以下、図面に示された実施例に基づいて本考案
を説明する。
Hereinafter, the present invention will be explained based on embodiments shown in the drawings.
第１図は、本考案の装置の回路構成を示したも
ので、Ｐは地中に埋設されたガス管、水道管など
の電気防食の対象となる鉄管であり、Mgは流電
陽極で、鉄より低電位の例えば亜鉛、マグネシウ
ムなどの金属からなる。Ａは、鉄其の他の低電位
金属の低抵抗接地体である。TR1はNPN型のト
ランジスター、TR2はNPN型のトランジスター
で、トランジスターTR1のベースB1と、トラン
ジスターTR2のコレクターC2とは接続される。
エミツターE1には通電々極Ａを接続し、ベース
B2には流電陽極Mg、エミツターE2には、電源
DCの極と、防食対象管路Ｐを夫々接続する。 Figure 1 shows the circuit configuration of the device of the present invention, where P is an iron pipe that is subject to cathodic protection such as gas pipes and water pipes buried underground, Mg is a galvanic anode, It is made of metals such as zinc and magnesium, which have a lower potential than iron. A is a low resistance grounding body made of iron or other low potential metal. TR 1 is an NPN type transistor, TR 2 is an NPN type transistor, and the base B 1 of the transistor TR 1 and the collector C 2 of the transistor TR 2 are connected.
Connect current-carrying terminal A to emitter E 1 , and
B2 has an Mg galvanic anode, and emitter E2 has a power supply.
Connect the DC poles and the pipe P to be protected against corrosion.
第２図は、無防食の場合、電気軌条Ｒからの迷
走電流により、埋設鉄管P1に電食が発生する場
合の説明図であり、矢印は電流の流入、流出方向
を示している。 FIG. 2 is an explanatory diagram of the case where electrolytic corrosion occurs in the buried iron pipe P1 due to stray current from the electric rail R in the case of no corrosion protection, and the arrows indicate the inflow and outflow directions of the current.
第３図は、外部電源式による過防食の説明図で
あり、DC1は電源で、A1は通電々極を示す。 FIG. 3 is an explanatory diagram of excessive corrosion protection using an external power source, where DC 1 is the power source and A 1 is the current-carrying terminal.
第４図は、定電圧直流電源DC2を共用し、本考
案の定電位制御装置の複数ａ，ｂを埋設鉄管P1
に並設した実施例を示したものである。 Fig. 4 shows a plurality of constant potential control devices a and b of the present invention that share a constant voltage DC power supply DC 2 and are installed in a buried iron pipe P1.
This figure shows an example in which the two are arranged in parallel.
二基の定電位制御装置ａ，ｂに於て、PNP型
トランジスターTR2a、TR2bbにおけるエミツタ
ーE2a、E2bは、各々埋設鉄管P1に接続し、コレク
ターC2a及びC2bは夫々NPN型トランジスター
TR1aと、TR1bのベースB1a，B1bと接続し、定電
圧直流電源DC2の極には、定電位制御装置ａ及
びｂのコレクターC1a及びC1bを並列接続し、エミ
ツターE1aと、E1bとの先端は夫々通電々極Aa及
びAbに接続し、PNP型トランジスターTR2aと、
TR2bのベースB2a、ベースB2bの先端には各々通
電陽極Mga、Mgbを設ける。 In the two constant potential controllers a and b, the emitters E 2a and E 2b of the PNP transistors TR 2 a and TR 2 bb are connected to the buried iron pipe P 1 , respectively, and the collectors C 2a and C 2b are respectively connected to the buried iron pipe P 1. NPN transistor
TR 1a is connected to the bases B 1a and B 1b of TR 1b , collectors C 1a and C 1b of constant potential controllers a and b are connected in parallel to the pole of constant voltage DC power supply DC 2 , and emitter E 1a is connected to the bases B 1a and B 1b of TR 1b. The tips of E 1b and E 1b are connected to current-carrying poles Aa and Ab, respectively, and the PNP transistor TR 2a ,
Current-carrying anodes Mga and Mgb are provided at the tips of the base B 2a and base B 2b of TR 2b , respectively.
このような場合に、電気軌条Ｒの近傍の埋設鉄
管P1には、電気軌条Ｒからの迷走電流が流入す
ると共に、定電位制御装置ａ及びｂからの防食電
流も流入するための埋設鉄管P1は、過防食の傾
向になるので、定電位制御装置ａを未通電にして
制御する。 In such a case, the stray current from the electric rail R flows into the buried iron pipe P 1 near the electric rail R, and the buried iron pipe P 1 is used to allow the stray current from the electric rail R to flow as well as the anticorrosion current from the constant potential control devices a and b. In case 1 , there is a tendency for over-corrosion protection, so the constant potential control device a is controlled in a non-energized state.
また、埋設鉄管P1の末端部に於ては、電流の
流出が行なわれるために電食傾向を示す。従つて
定電位制御装置ｂを通電することにより電食を防
止することができる。 Furthermore, the end portion of the buried iron pipe P1 exhibits a tendency for electrolytic corrosion due to current flowing out. Therefore, electrolytic corrosion can be prevented by energizing the constant potential control device b.
第５図は、本考案の装置を多段増幅する場合の
他の実施例を示した結線図であり、トランジスタ
ーの増幅機能を効果的にするために多段増幅して
微少なベース電流によつて、大電流を得られるも
のであり、この場合のトランジスターは、PNP
型トランジスターのTR2以外は総べてNPN型ト
ランジスターTR1、TR2…を使用する。なお図中
のSAはサージ吸収素子である。 FIG. 5 is a wiring diagram showing another embodiment in which the device of the present invention is amplified in multiple stages. A large current can be obtained, and the transistor in this case is a PNP
Except for the type transistor TR 2 , all NPN type transistors TR 1 , TR 2 , etc. are used. Note that SA in the figure is a surge absorption element.
上述の如く、本考案の定電位制御装置の構成、
作用によれば、
(1) 管対地電位を定電位制御できるので、高電位
の現出を防止するために管対地電位を全体的に
低位とするような通電々流は不要となる。
As mentioned above, the configuration of the constant potential control device of the present invention,
According to the functions, (1) Since the tube-to-ground potential can be controlled at a constant potential, there is no need for current flow to lower the tube-to-ground potential as a whole in order to prevent the appearance of a high potential.
(2) 埋設管の過防食は、管体被覆の剥離を起した
り、他の埋設管に干渉などを誘発するので、こ
のような過防食を防止することによつて他の埋
設管への影響を小さく出来る。(2) Over-corrosion protection of buried pipes can cause peeling of the pipe body coating and interference with other buried pipes, so by preventing such over-corrosion, it is possible to reduce the risk of damage to other buried pipes. The impact can be reduced.
(3) 既存の直流電源装置を定電位制御方式直流電
源装置に取替えるより安価となる。(3) It is cheaper than replacing the existing DC power supply with a constant potential control type DC power supply.
(4) 一つの既存直流電源装置を使用して、定電位
制御する位置、時間が異つても本装置を複数ケ
所に使用することにより、定電位制御が可能と
なる。(4) By using one existing DC power supply device, constant potential control is possible by using this device at multiple locations even if the positions and times for constant potential control are different.
(5) 太陽電池とバツテリーにより防食電流を通電
している場合、本考案の定電位制御装置を組合
わせれば、通電々流は、管対地電位の状況に応
じて制御されるので、夜間などに於ては防食設
定電位に応じた復極防止分のみの通電を行ない
得るなど多大な効果を奏する。(5) When a solar cell and battery are used to supply anti-corrosion current, if the constant potential control device of the present invention is combined, the current is controlled according to the condition of the pipe-to-ground potential, so it can be used at night, etc. This has great effects, such as being able to energize only the depolarization prevention amount according to the corrosion prevention setting potential.
第１図は、本考案の装置の回路を示す結線図、
第２図は、無防食時に発生する電食を示す説明
図、第３図は、外部電源式の防食装置の説明図、
第４図は、本考案の一実施例を示す回路図、第５
図は本考案の多段増幅を示す場合の回路図であ
る。
ａ，ｂ……定電位制御装置、Ａ，A1，A2、
Aa，Ab……通電々極、B1，B2，B1a，B1b、
B2a、B2b……ベース端子、C1，C2，C1a，C1b，
C2a，C2b……コレクタ端子、DC，DC1，DC2……
定電圧直流電源、Mg，Mg1，Mg2，Mga，Mgb
……通電陽極、Ｐ……防食対象管路、P1……埋
設鉄管、Ｒ……電気軌条、TR1，TR1a，TR1b…
…NPN型（第１）トランジスター、TR2，
TR2a，TR2b……PNP型（第２）トランジスタ
ー、……流出、流入電流の方向。
FIG. 1 is a wiring diagram showing the circuit of the device of the present invention;
Fig. 2 is an explanatory diagram showing electrolytic corrosion that occurs when no corrosion protection is performed; Fig. 3 is an explanatory diagram of an externally powered corrosion protection device;
FIG. 4 is a circuit diagram showing an embodiment of the present invention;
The figure is a circuit diagram showing the multistage amplification of the present invention. a, b... Constant potential control device, A, A 1 , A 2 ,
Aa, Ab... Current-carrying electrodes, B 1 , B 2 , B 1a , B 1b ,
B 2a , B 2b ...Base terminal, C 1 , C 2 , C 1a , C 1b ,
C 2a , C 2b ... Collector terminal, DC, DC 1 , DC 2 ...
Constant voltage DC power supply, Mg, Mg 1 , Mg 2 , Mga, Mgb
... Current-carrying anode, P ... Corrosion-protected pipeline, P 1 ... Buried iron pipe, R ... Electric rail, TR 1 , TR 1a , TR 1b ...
...NPN type (first) transistor, TR 2 ,
TR 2a , TR 2b ...PNP type (second) transistor...direction of outflow and inflow current.
Claims (1)
流電源を接続した電気防食用外部電源装置におい
て、 該定電圧直流電源と、前記通電々極との間に、
第１ランジスターを挿入接続し、更に前記防食対
象管路と、その近傍に新たに設けた流電陽極との
間に第２トランジスターのエミツタとベースを接
続し、該第２トランジスターのコレクターは、前
記第１トランジスターのベースに接続した回路よ
りなる定電位制御装置。[Scope of Claim for Utility Model Registration] In an external power supply device for cathodic protection in which a constant voltage DC power source is connected between a pipeline to be protected against corrosion and a current-carrying electrode, the constant-voltage DC power source and the current-carrying electrode are Between,
A first transistor is inserted and connected, and the emitter and base of a second transistor are connected between the corrosion-protected pipe line and a newly provided galvanic anode in the vicinity thereof, and the collector of the second transistor is A constant potential control device comprising a circuit connected to the base of the first transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9431485U JPH0318503Y2 (en) | 1985-06-21 | 1985-06-21 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9431485U JPH0318503Y2 (en) | 1985-06-21 | 1985-06-21 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS623576U JPS623576U (en) | 1987-01-10 |
| JPH0318503Y2 true JPH0318503Y2 (en) | 1991-04-18 |
Family
ID=30652760
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9431485U Expired JPH0318503Y2 (en) | 1985-06-21 | 1985-06-21 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0318503Y2 (en) |
-
1985
- 1985-06-21 JP JP9431485U patent/JPH0318503Y2/ja not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS623576U (en) | 1987-01-10 |
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