Have you ever encountered a shortened service life of a sheathed electric heater due to medium corrosion or wiring errors during selection? The following points are for reference by design and selection personnel.
Carbon steel sheaths are suitable for neutral water, mineral oil, and other weakly corrosive media, with lower cost; 304 stainless steel can handle weakly acidic and alkaline environments and some organic solvents; 316L stainless steel is suitable for occasions with high chloride ion content, such as certain chemical reactor jacket heating. Before selection, confirm the medium composition and concentration to avoid premature sheath failure.
In the heater circulation system, antifreeze suitable for the external ambient temperature should be used as the circulating heating medium. The freezing point of the antifreeze must be lower than the local minimum ambient temperature, and its concentration should be regularly tested to prevent pipeline rupture from freezing at low temperatures or vaporization from boiling at high temperatures.
The control cabinet is equipped with an RS-485 interface, supporting Modbus protocol connection to the host computer, facilitating centralized viewing of operating current and temperature curves of multiple heaters in the duty room. During wiring, verify the voltage level and power, ensure the terminal screws are tightened, and avoid overheating due to poor contact.
Regularly clean scale and carbon deposits on the sheath surface, and check insulation resistance (recommended not less than 1MΩ). If abnormal current fluctuations or temperature control deviations are found, stop the machine promptly for troubleshooting. For long-term shutdown, drain the medium to prevent internal corrosion.
