The oven heating tube is also called the boiler electric heating tube. The heating tube is made of metal tube. The spiral electric heating alloy wire (nickel chrome, iron chrome alloy) is uniformly distributed along the center of the tube. The gap filling compaction has good insulation and thermal conductivity. Magnesia oxide sand, sealed at both ends with silicone or ceramic, this metal armored heating element can heat air, metal molds and various liquids.The high-temperature resistance wire is uniformly distributed in the high-temperature resistant stainless steel seamless tube, and the crystalline magnesium oxide powder having good thermal conductivity and insulation performance is densely filled in the void portion, and the structure is advanced not only advanced, but also has high heat efficiency and uniform heat generation. When a current flows through the resistance wire, the generated heat is diffused to the surface of the metal tube by the crystalline magnesium oxide powder, and then transferred to the heated member or the air to achieve the purpose of heating.