When it comes to industrial heating solutions, tubular heaters are some of the most versatile and widely used options. These heaters offer consistent, reliable heat output across a range of applications, from packaging and food processing to HVAC systems and medical equipment. However, selecting the right tubular heater for your specific needs can be challenging due to the variety of options available. At Nexthermal, we understand that choosing the right heating element is crucial to ensure efficiency, safety, and performance in your application.
In this guide, we will walk you through the key factors to consider when selecting the ideal tubular heater for your application, including material choice, watt density, and mounting options.
What are Tubular Heaters?
Tubular heaters are electrical heating elements made from a metal tube that contains a heating wire and is filled with a dielectric material such as magnesium oxide (MgO). The design allows for a high degree of flexibility, enabling manufacturers to create heaters in various shapes and sizes. Tubular heaters are ideal for both direct and indirect heating applications and are commonly used in industries like automotive, food processing, pharmaceuticals, plastics, and packaging.
Now that we have an overview of tubular heaters, let’s dive into the key factors that influence your choice when selecting the right one for your needs.
1. Material Selection: Choosing the Right Alloy
The material of the tubular heater is one of the most important considerations when selecting the right heating solution. The material used for the tube, the heating wire, and the dielectric filler all impact the heater’s performance, durability, and resistance to corrosion.
Common Tubular Heater Materials
- Stainless Steel:
Stainless steel is the most common material for tubular heaters. It offers excellent resistance to corrosion and high-temperature environments, making it ideal for applications in food processing, HVAC, and other industries where hygiene and durability are essential. It is highly resistant to oxidation and offers good mechanical strength. - Incoloy (Alloy 800):
Incoloy is a nickel-based alloy known for its ability to withstand high temperatures and corrosive environments. It is often used in applications that require higher temperature ranges, such as aerospace and certain chemical processing industries. - Copper:
Copper is an excellent conductor of heat and electricity, making it ideal for applications that require fast heating and high efficiency. However, copper is more prone to corrosion than stainless steel, so it is typically used in controlled environments where the risk of corrosion is minimal. - Nickel-Chromium Alloys:
Nickel-chromium alloys are typically used in high-temperature environments and offer excellent resistance to oxidation. They are commonly found in industrial ovens, furnaces, and other high-heat applications.
How to Choose the Right Material?
- Corrosion Resistance: If your application involves exposure to moisture or chemicals, choosing materials like stainless steel or Incoloy can prevent premature degradation.
- Temperature Resistance: For applications requiring higher temperature ranges, materials like Incoloy or nickel-chromium alloys are best suited.
- Conductivity: If rapid heat-up times are critical, copper is an excellent choice due to its superior heat conductivity.
2. Watt Density: Optimizing Heat Output
Watt density refers to the amount of power (in watts) that is applied to a given surface area of the heating element. It plays a significant role in determining the efficiency and longevity of your tubular heater.
What is Watt Density?
Watt density is calculated by dividing the total wattage of the heater by the heating surface area. For example, a heater with 100 watts applied to a surface area of 50 square inches would have a watt density of 2 watts per square inch.
How to Choose the Right Watt Density for Your Application?
- Low Watt Density (0.5–1 W/in²):
Low watt densities are suitable for applications that require even, gentle heating. These are often used in air heaters and oven heating elements where excessive heat buildup could damage the system. Low watt density is also ideal for maintaining consistent, moderate temperatures in delicate processes. - Medium Watt Density (1–2 W/in²):
Medium watt density heaters are versatile and used in a wide range of applications such as packaging machinery, plastic molding, and water heating. These provide a balance of rapid heating while maintaining good durability. - High Watt Density (2–4 W/in²):
High watt density is used in applications that require quick, intense heating, such as industrial ovens and hot stamping machines. These heaters are typically designed to handle high temperatures and provide concentrated heat output in a smaller area.
Choosing the Right Watt Density
- If you need to heat a large area or maintain a consistent, lower temperature, low watt density is the best option.
- For applications where space is limited and higher heat output is required, such as in plastic extrusion or food processing, medium to high watt densities are often necessary.
- High watt density is ideal for applications like high-temperature ovens and heat treat furnaces where rapid and intense heat is required.
3. Mounting Options: Ensuring Proper Integration
The way the tubular heater is mounted in your system is another important factor in selecting the right heating solution. Mounting styles can vary based on the type of application and the equipment involved. Common mounting options for tubular heaters include:
- Flanged Mounting:
Flanged mounting is one of the most common mounting methods for industrial heating systems. It is suitable for systems that require easy installation and replacement. Flanges allow the heater to be attached securely to tanks, pipes, or other equipment. - Compression Fittings:
Compression fittings are used to secure the heater to surfaces where a tighter seal is necessary. These are often used in situations where the heater needs to fit tightly into a tube or pipe to avoid heat loss. - Threaded Mounting:
Threaded tubular heaters are often used in compact spaces where other mounting styles may not fit. Threaded heaters offer easy installation and are often used in applications where vibration or movement is involved. - Bendable or Custom Mounting:
In some applications, tubular heaters need to be custom-shaped or bent to fit a specific configuration. Custom bending allows for flexibility in design, especially in extrusion machines or other applications where space is constrained.
Choosing the Right Mounting Option
- If your application requires frequent maintenance or replacement, flanged mounting is ideal due to its ease of installation.
- For high-vibration environments, a secure threaded or compression mount may be the best option.
- If your equipment has space constraints, custom bending or flexible mounting configurations can provide an effective solution.
4. Other Factors to Consider
While material, watt density, and mounting options are some of the most important considerations, other factors should also be taken into account when selecting your tubular heater:
- Voltage and Power Supply: Ensure that the heater is compatible with your system’s voltage and power requirements.
- Insulation: The type of insulation around the heater affects its heat retention and energy efficiency. Consider using ceramic or fiberglass insulation for better heat control.
- Size and Shape: Tubular heaters come in various sizes and can be bent or shaped to meet the requirements of your system.
Conclusion
Choosing the right tubular heater involves a detailed evaluation of your application’s unique requirements. Consider the material, watt density, and mounting options to ensure optimal performance, longevity, and energy efficiency. By working with a trusted manufacturer like Nexthermal, you can receive expert guidance and tailored heating solutions that meet the demands of your industry.
Whether you need a simple solution for general heating or a custom-designed system for a complex application, Nexthermal offers high-quality tubular heaters to help you achieve the best results.
