When a brand-new air fryer emits white smoke during its initial uses, it is frequently attributed to an overlooked procedure in the heating element manufacturing process: Silicone Oil Immersion.
During the production of tubular heating elements, particularly after the swaging process, the magnesium oxide (MgO) powder at the tube ends remains exposed. MgO is highly hygroscopic, easily absorbing ambient moisture while also retaining trace amounts of processing lubricants. Without adequate sealing, the intense heat during the appliance's first power-on causes this moisture to vaporize and residual oils to volatilize, producing a burst of white smoke. The silicone oil immersion process is strictly implemented to resolve this specific industry challenge.
The fundamental objective of silicone oil immersion is twofold: achieving total moisture isolation and permanently sealing internal volatile contaminants.
High-grade methyl silicone oil provides exceptional thermal stability and powerful hydrophobicity. During the immersion process, capillary action draws the liquid silicone deep into the microscopic voids of the MgO powder at the tube ends. This displaces trapped air and moisture, curing into a resilient waterproof barrier. This invisible film effectively locks out external moisture during transit and storage, while simultaneously suppressing any internal residues from volatilizing into smoke when first heated.
Omitting or compromising this procedure inevitably leads to initial smoking. More critically, over extended usage cycles, continuous moisture ingress will degrade the element’s insulation resistance, posing serious safety and performance risks.
At Shenzhen Angel Electric Heater Co., Ltd., silicone oil sealing is a highly calibrated, critical control operation rather than a simple dip. Below is our standardized enforcement procedure:
| Process Step | Execution Detail | Purpose & Benefit |
|---|---|---|
| 1. Tube End Preparation | Post-welding of terminal pins, the tube openings undergo precise mechanical cleaning to eliminate micro-burrs and metallic dust. | Ensures unobstructed capillary pathways for full oil penetration. |
| 2. Precise Dual-End Immersion | Elements are vertically lowered into high-temperature methyl silicone oil. Depth is strictly controlled to 10-15mm based on tube diameter. | Achieves thorough core penetration without excessive saturation. |
| 3. Vertical Draining | The processed elements are extracted and placed in a vertical rack to drain naturally via gravity. | Allows the oil to diffuse further and distribute evenly within the powder layer. |
| 4. Lint-Free Wiping | Technicians utilize industrial lint-free cloths to wipe away excess superficial oil from the tube body and terminal pins. | Maintains cosmetic compliance and prevents dust adhesion prior to assembly. |
| 5. Thermal Stabilization | The tubes proceed into a dedicated drying tunnel line for high-temperature baking. | Enhances thermal stability, forming a highly durable hydrophobic layer. |
Step 2: Immersion Depth Control
Step 3: Vertical Draining
Step 4: Lint-Free Wiping
As a professional heating element manufacturer with nearly 30 years of expertise, Shenzhen Angel Electric Heater Co., Ltd. designates silicone oil immersion as a Key Quality Control Point (KQCP). We strictly audit every detail—from basic silicone oil purity and precise penetration depth to baking temperature.
Combined with rigorous quality assurance checks, including comprehensive Insulation Resistance and Hi-Pot Testing, we ensure that every Dry-Burning Heating Element delivered achieves zero smoke on first use and reliable performance over the long term.
Choose Shenzhen Angel Electric Heater Co., Ltd. to equip your kitchen appliances with a robust, reliable, and premium heat source that guarantees end-user satisfaction from the very first plug-in.
