The meltblowing process requires a substantial amount of hot air. The compressed air output from the air compressor is dehumidified and filtered before being sent to the air heater for warming, and then it is delivered to the meltblowing die assembly. The air heater is a pressure vessel that must also withstand the oxidation effects of high-temperature air, thus stainless steel materials must be used. The heating element of the air heater is a stainless steel electric heating tube. Multiple baffle plates are set inside the heater to extend the air's residence time within the heater, enhancing heat exchange efficiency. Increasing the number of heating tubes and boosting the installed power of the air heater can shorten the startup and warming time of the production line. The meltblowing process demands high precision in temperature control for the stretching air heater, with the stretching air temperature needing to be maintained within ±1°C.

Principle of Operation

A primary coil with a higher number of turns and a secondary coil with a lower number of turns are mounted on the same core. The voltage ratio between input and output equals the ratio of the coil turns, while the energy remains constant. Consequently, the secondary coil produces a high current under low-voltage conditions. For induction heaters, the bearing acts as a short-circuited single-turn secondary coil, passing a high current at lower AC voltages, thus generating a significant amount of heat. The heater itself and the magnetic yoke remain at a constant temperature. Since this heating method induces current, the bearing becomes magnetized. It is crucial to demagnetize the bearing afterward to prevent it from attracting metal magnetic particles during operation. FAG induction heaters all come with an automatic demagnetization feature.

This technology utilizes the principle of eddy current generation in alternating magnetic fields, causing the material to heat up, commonly employed in metal heat treatment applications. The mechanism involves thicker metals, when subjected to an alternating magnetic field, produce currents due to electromagnetic induction. Once these currents are generated in the thicker metal, they create spiral flow paths within the material. Consequently, the heat generated by the current flow is absorbed by the metal itself, leading to rapid temperature increase.

Uniformly distributed within the high-temperature resistant stainless steel seamless pipe are high-temperature resistance wires, and in the gaps, a dense filling of crystalline magnesium oxide powder with excellent thermal conductivity and insulation properties. This structure is not only advanced and highly efficient in heat transfer but also ensures even heating. When an electric current passes through the high-temperature resistance wires, the heat generated is diffused through the crystalline magnesium oxide powder to the surface of the metal pipe, and then transferred to the heated object or air, achieving the purpose of heating.

The air electric heater is primarily used to heat the required airflow from the initial temperature to the desired air temperature, up to a maximum of 850°C.

Technical Features

The air can be heated to a very high temperature, up to 450°C, with the shell temperature around 50°C.

2. High Efficiency: Over 0.9.

Step-up and step-down rates are fast and stable, reaching up to 10℃/s. It prevents temperature control drift due to the phenomenon of overshooting and lag in controlled air temperature, making it highly suitable for automatic control.

4. Excellent Mechanical Performance: Thanks to its specialized alloy material heating element, it outperforms any heating element in terms of mechanical properties and strength under the impact of high-pressure air flow. This provides a significant advantage for systems and accessories that require continuous and prolonged air heating.

5. Durable and long-lasting, with a lifespan of several decades when used in accordance with operating procedures.

6. Clean air, compact in size.

Application Fields

The Application Scope of Heaters: Air heaters are a widely used type of heater, commonly referred to as such in everyday language. In reality, they can be further categorized into many types based on the heated gas, with common ones including nitrogen heaters and hydrogen heaters. These can also be known as pipeline gas heaters. They have been extensively applied in aerospace, arms industry, chemical industry, and many scientific research and production laboratories in colleges and universities. They are particularly suitable for automatic temperature control systems with high flow rates and high-temperature attachments testing. The range of air electric heaters is broad: they can heat any gas, producing dry, moisture-free hot air that is non-conductive, non-flammable, non-explosive, non-corrosive, non-polluting, safe and reliable, with rapid heating of the heated space (可控).