Your brand-new air fryer emits white smoke the first few times you use it? Don't blame the appliance quality just yet—this is often a telltale sign that a critical step in the heating element manufacturing process—Silicone Oil Immersion—wasn't done properly.
During the production of heating elements, especially after the Swaging process, the magnesium oxide powder at the tube ends easily absorbs moisture from the air and retains trace amounts of processing lubricant. Without special treatment, when electricity is first applied, this moisture vaporizes and the oil volatilizes instantly under high heat, creating that unpleasant "white smoke." The silicone oil immersion process is specifically designed to eliminate this pain point.
Why Must Heating Elements Be Immersed in Silicone Oil?
The core purpose of silicone oil immersion is twofold: deep moisture resistance and contaminant sealing.
Silicone oil boasts excellent high-temperature resistance and strong hydrophobicity. During immersion, liquid silicone oil utilizes capillary action to penetrate deep into the microscopic gaps of the magnesium oxide powder at the tube ends. It displaces air and moisture, forming an invisible hydrophobic protective film. This film effectively prevents external moisture from re-entering while simultaneously "locking in" any residual internal oil, preventing it from volatilizing and causing smoke during the initial heating.
If this process is skimped on, smoking upon heating is inevitable. Furthermore, over long-term use, moisture ingress will lead to decreased insulation resistance, creating a potential safety hazard.
The Standard Silicone Oil Immersion Process: Giving Both Ends a "Bath"
At Shenzhen Angel Electric Heater Co,.Ltd., silicone oil immersion is far more than a simple "dip"; it is a strictly enforced, standardized procedure:
Step 1: Tube End Preparation
After welding the terminal pins, the tube ends are cleaned to remove burrs and dust. This ensures the pathways for the silicone oil are clear, allowing for full penetration.
Step 2: Double-End Immersion with Precise Timing
Both ends of the heating element are vertically immersed in specialized, high-temperature resistant methyl silicone oil. The immersion depth is typically controlled to 10-15mm. The immersion time is precisely set based on the tube diameter and oil temperature to ensure the silicone oil fully penetrates to the core—neither excessive nor insufficient.
Step 3: Vertical Draining & Natural Permeation
After immersion, the tubes are removed and left to drain vertically. Gravity allows the silicone oil to diffuse further and distribute evenly within the powder layer.
Step 4: Lint-Free Wiping
A specialized lint-free cloth is used to wipe away excess surface oil from the tube ends and tube body. This maintains a clean product appearance and prevents dust from adhering, which could interfere with subsequent assembly.
Step 5: High-Temperature Stabilization
Finally, the tubes enter a drying line for baking at a specific temperature. This process enhances the thermal stability of the silicone oil, forming a durable, stable hydrophobic adsorption layer on the surface of the magnesium oxide powder.
The Angel Standard: Making "Smoking" a Thing of the Past
As a professional heating element manufacturer with 30 years of experience, Shenzhen Angel Electric Heater Co,.Ltd. designates silicone oil immersion as a Key Control Point. We strictly control every detail—from silicone oil quality and penetration depth to baking temperature—and combine this with rigorous testing like Insulation Resistance Tests and Hi-Pot Tests. This guarantees that every Dry-Burning Heating Element we ship truly achieves "no smoke on first use, and reliable performance over the long term."
Choose Shenzhen Angel Electric Heater Co.,Ltd.. Equip your kitchen appliances with the most reliable "heart" for pure and worry-free cooking every time.
