I: Introduction:
Long-lasting reference electrodes are used in soil media and are long-life electrodes for burial. They feature a ceramic pot structure design that ensures the permeation of copper sulfate and ion exchange, thereby guaranteeing the potential stability of the reference electrode. Additionally, this design effectively controls the loss rate of copper sulfate crystals, significantly extending the service life of the reference electrode.
II: Technical Parameters
Reference electrodes are installed in integrated track beds and tunnel structures to measure the polarization potential of structural steel, reflecting its corrosion status. The technical parameters are as follows:
1) Potential stability: ≤±20mV
2) Potential polarization: Potential fluctuation <±30mV under polarization current <5uA
3) Electrode dimensions: ?54X156mm
4) Electrode shell compressive strength: 10MPa
5) Service life: 10 years
III: Installation Method for Reference Electrodes
1. Pre-installation preparation
Before installation, the electrode must be soaked in clean tap water for 8–10 hours and then set aside for use.
2. Burial location
Tunnel reference electrodes must be buried near the reinforcement bars of the structure being measured, while track bed reference electrodes are buried near side terminal blocks (see construction drawings for details), with a distance of less than 15mm from the reinforcement bars (or steel). The electrode should be placed vertically and fully embedded in the concrete medium.
3. Drilling and installation
1) At the selected location, drill a hole with a diameter greater than 60mm and a depth greater than 180mm; remove concrete debris or dust from the hole and moisten the inner surface with tap water.
2) Mix the pre-prepared cement mortar filler with tap water to achieve a suitable consistency. Place a small amount of mortar at the bottom of the hole or square groove, and use an appropriate tool to apply the mortar evenly to the surrounding walls.
3) Apply a thin layer of mortar to the ceramic shell of the reference electrode and gently place it into the hole until the desired depth is reached.
4) Level the area above the buried electrode with mortar, ensuring it is as flush as possible with the surrounding concrete surface.
4. Wiring
The reference electrode lead wire is 6 meters long and uses a 1*2.5mm2 cable. Pass the electrode lead wire through a PVC conduit to the sensor and connect it to the sensor’s terminal block.
5. Precautions
1) The electrode features a porous ceramic shell, so handle it with care during use and installation, and avoid collisions with other rigid structures.
2) Do not pull the electrode lead wire forcefully to prevent breakage.
3) Before burial, store the electrode in a cool place, avoiding exposure to direct sunlight or rain.
Buried long-lasting reference electrodes (especially those used as control signal sources in impressed current cathodic protection) are critical components in engineering projects due to their durability, longevity, and resistance to damage.
During the construction of large oil storage tanks and large chemical container base plates for cathodic protection, heavy machinery and equipment are often used. As a result, buried long-lasting reference electrodes (conventional ceramic pot core type) installed before foundation construction are prone to being crushed or damaged. To address this issue, our company has independently developed a pressure-resistant, long-lasting copper sulfate reference electrode made of PVC and PPR materials. This reference electrode offers the same performance and service life as ceramic reference electrodes, with the added advantages of resistance to compression, impact, and dropping, making it widely applicable in various fields.
It can be used to measure the accurate potential of protected structures.
In impressed current cathodic protection, it can serve as a signal source for automatic control by potentiostats.
It can be buried at the bottom of large containers, such as large oil storage tanks and chemical containers, in locations where data detection is required but difficult to measure. With a long service life and stable signal output, it is an ideal tool for measuring cathodic protection potential.