The applied current method is to connect the negative electrode of the DC power supply with the protected body, so that the positive electrode is connected with the external power supply of the anode body. By the auxiliary anode, the protection current is introduced into the ground, and the current is smooth and smooth to the protected body through the electrolyte, so as to reduce the frequency of metal ionization oxidation reaction in the pipeline.

Cathodic protection 1: Sacrifice anode protection

As the best way to reduce the erosion of metal pipe, cathodic protection is to apply cathodic protection to the pipe so that the anodic material corrodes instead of the metal pipe.

Cathodic protection 2: impressed current

Disadvantages: limited applied potential, low output current, limited by soil resistivity.

Advantages: simple construction, low cost, no special treatment workers after installation, and low maintenance cost, small interference to other pipelines and so on

Sacrificial anode method is to use the principle of corrosion galvanic battery to protect the metal pipe, as long as the sacrificial anode is added to the protected metal, so that the protected metal becomes the cathode, can achieve the purpose of protecting the metal pipe.

Advantages: high applied potential, large output current, suitable for large departments of soil environment, flexible output potential and current control, easy determination of anti-corrosion effect, low operating cost, etc.

Disadvantages: high installation cost, need certain operation and maintenance cost, but also to the external pipe stray current interference.

What are the advantages and disadvantages of sacrificial anode protection and impressed current protection

. Due to the difference of pipeline properties, the content of cathodic protection construction is also different, the common methods are: sacrifice anode method and impressed current method.