In petrochemical industry, marine engineering, pipeline transportation and other fields involving metal
anticorrosion, the cathodic stripping machine, as an important part of electrochemical protection system,
is playing an irreplaceable role. This paper will deeply analyze its working principle, technical advantages
and practical application scenarios to provide professional reference for industry practitioners.
The basic principle of cathodic protection technology
Metal equipment will accelerate rusting and corrosion due to electrochemical reaction in corrosive
environments such as humid and salt-containing environments. Cathodic protection technology
inhibits the oxidation reaction by applying an external current to form a potential difference, making
the protected metal a cathode. As the core execution unit of this technology, the cathodic stripping
machine ensures that the protection potential is always in the optimal range by intelligently
regulating the current output.
Its working process contains three key links:
Real-time monitoring of the potential value of the protected object
Dynamic adjustment of the output current strength
Balancing the consumption rate of anode materials
The closed-loop control system can improve the protection efficiency by more than 40%, especially
suitable for buried pipelines, oil storage tanks and other facilities difficult to be visually inspected.
Core technical components of the equipment
Modern cathode stripping machine has developed into an integrated intelligent system, which contains
the following core technical modules:
1. Constant Potential Control Unit
Adopts PID algorithm to adjust the output voltage in real time, controlling the fluctuation of protection
potential within the range of ±5mV. Dual redundant circuit design ensures stable operation in extreme
environments.
2. Remote monitoring system
Supports 4G/5G wireless transmission, and can view in real time:
Equipment operation status
Historical data curve
Abnormal alarm record
Realizes multi-node centralized management through cloud platform, which greatly reduces inspection cost.
3. Adaptive power supply module
Wide voltage input design (100-500V AC) to adapt to the complex grid environment, conversion efficiency
of more than 92%. Modularized structure facilitates rapid replacement and maintenance on site.
Typical Application Scenario Analysis
Scenario 1: Offshore Wind Power Foundation Protection
Conduit rack foundation is facing serious corrosion in seawater full immersion area, after a project adopts
distributed cathodic stripping system:
The protection current density is stabilized at 120mA/m²
The expected service life is prolonged to 35 years
Maintenance cost is reduced by 60%
Scenario 2: Urban Gas Pipeline Networks
In response to the problem of aging of the PE anticorrosive layer, the intelligent stripping machine can accurately
control the protection range: Effectively inhibit the corrosion under the 3PE layer
Potential gradient fluctuation <8%
Realize the annual maintenance cost saving of 23,000 RMB per kilometer of pipeline
Scenario 3: Tank bottom protection
Through the cooperation of annular anode and stripper, solve the pain point of uneven current distribution of the
traditional sacrificial anode method:
The uniformity of the protection potential is increased to 95%
The rate of consumption of the anode material is reduced by 42%
The corrosion rate of the bottom plate is controlled to be less than 0.02mm/year
Selection of Equipment Key indexes
When choosing cathode stripping machine, you should focus on:
Indicator items Reference standard Testing method
Output current accuracy ≤±1% full scale Continuous test with constant resistance load
Environmental adaptability IP65 protection level Salt spray test ≥1000 hours
Data sampling frequency ≥1 time/second Analog sudden change signal response test
Fault self-diagnosis 16 types of common fault code identification Forced triggering of abnormal conditions
It is recommended to prioritize equipment with It is recommended to choose the equipment with the
following characteristics:
Support MODBUS/Profibus industrial protocols
Equipped with lightning surge protection device
Provide local/remote dual control mode
With over-current, over-voltage, overheating triple protection
Operation and maintenance management key points
Daily maintenance:
Monthly inspection of terminal tightness
Quarterly cleaning of the thermal channel dust
Annual calibration of the potential measurement module
Troubleshooting process:
Check the status of the power indicator
Measurement of the output of the open circuit Voltage
Verify the validity of reference electrodes
Analyze the characteristics of historical data curves
Life extension measures:
Add cooling fans in high-temperature environments
Add moisture-proof sealing layers in rainy areas
Configure voltage regulators when the power grid fluctuates a lot
Technology Development Trends
1. Integration of new energy sources
PV-Cathodic Protection Hybrid Power Supply System is already in the field test stage, which reduces the dependence on
external power supply by 70%. A test project realizes 72 hours of continuous off-grid operation.
2. Artificial Intelligence Application
Through machine learning algorithms:
Predict the remaining life of anode materials (error <8%)
Automatically optimize the combination of output parameters
Identify early corrosion characteristic signals
3. Miniaturization Design
Adopting GaN power devices, the new generation of equipment is reduced in size by 40%, and the power density is
increased to 5W/cm³, which is especially suitable for space-constrained retrofit projects.
[Conclusion]
With the implementation of new standards such as the Technical Specification for Industrial Corrosion Prevention, cathodic
strippers are evolving from a single protection device to an intelligent management system. In the next five years, a new
generation of equipment with self-diagnostic and self-adaptive features will occupy more than 60% of the market share.
It is recommended that relevant enterprises focus on the three technical directions of material innovation, data integration
and energy efficiency optimization to grasp the market opportunities brought by industrial upgrading.