The vast majority of pipelines used for transporting liquids such as oil, natural gas, and water are steel pipelines. These steel pipelines are made of alloy steel, such as Grade 20 steel, and are generally buried in soil. However, buried steel pipelines face the issue of corrosion, which is generally divided into two types: internal corrosion and external corrosion. Internal corrosion is less common, while external corrosion is more prevalent. The primary protective measures to prevent pipeline corrosion include applying anti-corrosion coatings and applying a negative potential to the pipeline using a constant potential instrument or sacrificial anode method, making the pipeline act as a cathode relative to the ground, thereby forming protection and slowing down corrosion.
Intelligent test stations are an indispensable component of the cathodic protection system, primarily used for detecting the effectiveness of cathodic protection and operational parameters. They are typically placed at intervals of approximately 1 km. Measurements are currently conducted manually each time, with cumbersome steps and a long time required to complete all data measurements. The excessive time wasted on measurements makes the manual method inefficient and unreliable. Additionally, the high risk factor during field measurements makes it unable to meet the long-term measurement needs of pipelines, necessitating a more stable and efficient method for replacement. Therefore, our company has planned, analyzed, and addressed the above issues by researching and designing intelligent test stations.
Intelligent test stations are equipped with a built-in low-power ARM MCU chip, enabling automatic hardware data collection and upload. They can simultaneously collect data such as on-potential, off-potential, natural potential, AC-induced voltage, and AC-induced current. These stations utilize wireless intelligent transmission, with preset timing mechanisms. When the internal clock reaches the specified time, the device automatically starts and collects data. The equipment employs mature and stable GPRS or NB-IOT wireless data communication for transmission. Our company's current intelligent test station technology is mature and has received very positive feedback in the market. The application of intelligent test stations has significantly reduced inefficiencies and low reliability associated with manual methods.
The complete automatic cathodic protection potential collection system should be capable of automatically collecting, storing, and uploading cathodic protection parameters (such as natural potential, on-potential, off-potential, and pipeline AC interference voltage) according to set requirements, and should be compatible with system software. In addition to the conventional type, triggered automatic cathodic protection potential collectors should also have the function of monitoring and recording the intensity and duration of randomly occurring strong DC interference.
The design of the automatic cathodic protection potential collector should be fully responsible by the supplier. The supplier's design should meet the requirements of the technical specifications, standards, relevant documents, and regulations, as well as the performance, safety, and maintenance requirements of the product.
The automatic cathodic protection potential collector and its accompanying test stations should be supplied as a complete set. The supplier should also be able to provide matching management software and accessory parts. The automatic cathodic protection potential collector should adopt a unified communication protocol and meet the operational management needs of the pipeline.
Depending on the field conditions, installation methods such as inside test stations or protective boxes can be chosen.
The automatic cathodic protection potential collection system should consider the convenience of later replacements, such as batteries and IoT cards.
The operating temperature of the main unit of the automatic potential collector should preferably be: -25°C to +55°C, while also meeting the environmental temperature requirements of the installation location.
The automatic potential collector should be compatible with the communication conditions of the installation site.