The service life of PFA anti-corrosion heaters is not only related to product quality, but also closely related to installation and daily maintenance. Improper installation can easily cause coating damage and lead to early failure; scientific daily maintenance can extend the service life by 30% to 50%. Mastering standardized installation procedures and daily maintenance methods is essential for the long-term stable operation of equipment.
Before installation, comprehensive inspection and preparation should be done first. Check whether the appearance of the heater is intact, and whether there are scratches, bumps and peeling on the PFA coating during transportation; use a spark detector to conduct a second pinhole test to ensure that the coating is still intact after transportation. Check whether the tank size and installation position match the heater size, and reserve sufficient operation space. Prepare necessary installation tools and protective measures, and prepare soft lifting ropes and gaskets to avoid scratching the coating during installation.
During installation, the protection of PFA coating is the top priority. When hoisting, use soft fabric straps instead of steel wire ropes to avoid scratching the coating surface; when placing it into the tank, move it slowly to avoid collision with the tank wall and internal components. For L-shaped hanging heaters, the contact position between the hanging part and the tank wall should be padded with insulating gaskets to avoid friction damage to the coating during long-term use. For flange-mounted heaters, tighten the bolts evenly and symmetrically to prevent uneven stress from causing coating damage at the flange root. The wiring part should be kept above the liquid level, and waterproof and anti-corrosion treatment should be done to avoid corrosive gas from corroding the terminal.
During commissioning and trial operation, do not energize and heat at full power immediately. First confirm that the liquid level has completely submerged the heating part, then power on and heat at low power for preheating, and gradually increase to the rated power after the temperature rises. It is strictly forbidden to dry burn - the heater must be completely immersed in the liquid before power on, and the power must be cut off immediately when the liquid level drops. Install liquid level protection devices and over-temperature protection devices as much as possible to realize automatic power-off protection.
In terms of daily maintenance, regular appearance inspection should be done to check whether the coating has scratches, blistering and peeling; regularly clean the surface scale - because PFA has non-stick property, most scales can be removed by gentle brushing or water flushing, and do not scrape with sharp hard objects. Conduct a spark pinhole test every 3–6 months to find early coating damage in time. Regularly check the electrical insulation to ensure safety. When the heater is not used for a long time, it should be cleaned and lifted out of the tank, and stored in a dry and ventilated place to avoid long-term immersion.
For common minor faults, targeted treatment can be carried out. If there are slight scratches on the surface, PFA repair paste can be used for local repair; if the heating is uneven, check whether the power supply voltage is normal and whether there is local scaling; if the insulation resistance drops, check whether the wiring part is damp or the coating has hidden pinholes.
Table 1 Daily Maintenance Items and Periods for PFA Heaters
表格
| Maintenance Item | Inspection Cycle | Operation Key Point | Qualification Standard |
|---|---|---|---|
| Appearance Inspection | Monthly | Check scratches, blisters, peeling | No obvious coating damage |
| Surface Descaling | Every 1–3 months | Soft brush cleaning, water flushing | No thick scale deposition |
| Spark Pinhole Test | Every 3–6 months | Full tube scan with spark detector | No breakdown alarm |
| Insulation Resistance Test | Every 3 months | Measure with insulation tester | ≥50 MΩ |
| Liquid Level Device Check | Monthly | Test low-level protection function | Normal power-off protection |
| Terminal Check | Quarterly | Check for corrosion and looseness | Firm connection, no corrosion |
Standardized installation and scientific daily maintenance can effectively extend the service life of PFA heaters and reduce the overall operation cost.
