What factors affect the service life of silicone rubber electric heaters?

The service life of silicone rubber electric heating sheet is affected by many factors, as follows:
Material factors
Quality of silicone rubber: High-quality silicone rubber has good resistance to high temperature, aging and chemical corrosion. If the purity of silicone rubber is high and the degree of cross-linking is uniform, it can better withstand the thermal stress during long-term heating, and is not prone to aging phenomena such as cracking, hardening or softening, thereby extending the service life of the heating sheet.
Quality of resistance wire: The material of the resistance wire determines its high temperature resistance and oxidation resistance. For example, nickel-chromium alloy resistance wire has better oxidation resistance than iron-chromium-aluminum alloy resistance wire, can maintain good stability at high temperature, is not easy to break, and can extend the service life of the heating sheet. In addition, the uniformity of the diameter and cross-sectional area of ​​the resistance wire is also very important. Uneven places are prone to local overheating, which accelerates the aging of the resistance wire.
Working conditions
Working temperature: Working in a high temperature environment for a long time will accelerate the aging of silicone rubber and resistance wire. Generally speaking, silicone rubber electric heating sheets have their rated operating temperature range. Beyond this range, their service life will be greatly shortened for each temperature increase. For example, if the rated temperature exceeds 20℃, the service life may be reduced by half or more.
Voltage stability: Voltage fluctuations can cause unstable power of the heater. If the voltage is too high, the resistor current will be too large, generating too much heat, accelerating the oxidation of the resistor and the aging of the silicone rubber; if the voltage is too low, the heater cannot reach the normal operating temperature, which may cause changes in the performance of the internal components and affect the service life.
Working environment: If there are corrosive gases, moisture, dust, etc. in the working environment, it will have an adverse effect on the heater. Corrosive gases will corrode the resistor and silicone rubber and reduce their performance; a humid environment may cause a decline in insulation performance and cause faults such as short circuits; dust accumulates on the surface of the heater, which will affect heat dissipation, cause temperature rise, and accelerate aging.
Manufacturing process
Production process control: The vulcanization process and resistor winding process in the production process are crucial to the quality and service life of the heater. Improper vulcanization time and temperature control will make the performance of silicone rubber unstable; uneven winding of the resistor will cause uneven heat distribution, local overheating, and affect the service life.
Encapsulation quality: Good packaging can protect the internal resistor and silicone rubber from the influence of the external environment. If the package is not tight, the outside air, water vapor, etc. can easily enter the inside of the heating plate, accelerating the aging and corrosion of the components.
Use and maintenance
Installation method: When installing the heating plate, if it is installed too tight or too loose, it will have an adverse effect on it. Too tight will cause the heating plate to be subjected to additional stress when it expands due to heat, which may easily cause the silicone rubber to crack or the resistance wire to be damaged; too loose will cause a gap between the heating plate and the heated object, affecting the heat conduction effect and causing the local temperature to be too high.
Regular maintenance: Regularly check whether there is dust and debris on the surface of the heating plate. Timely cleaning can ensure good heat dissipation. At the same time, check whether the connection parts of the heating plate are loose. If there is any looseness, tighten it in time to prevent the contact resistance from increasing and causing overheating, which will help extend the service life of the heating plate.