Why Carbon Fiber Heating Tubes Smoke During First Use

Today, I’d like to share with everyone why the surface of a carbon fiber heating tube may emit smoke during its first use.

Background:

This customer works in the printing industry. The video the customer sent clearly showed smoke when the heating tube was powered on for the first time. The customer was worried that the heating tube was leaking, but that wasn’t the case. So, why does smoke appear? Allow me to explain in detail.

Clarifying Concerns About Leakage

First, let’s address the customer’s concern about the heating tube leaking. Carbon fiber heating tubes operate by using a quartz tube to create a vacuum environment, protecting the carbon fiber heating filament. The filament emits infrared energy through electrical power, which heats the object. If the tube were leaking, the vacuum would be compromised, and the carbon fiber would oxidize and break in less than a minute in a high-temperature, oxygen-rich environment. This breakage would result in a bright, glaring white light. Since no such light was observed in the video, we can confirm that the vacuum of the heating tube remains intact. But why was there smoke?

Source of the Smoke

The smoke observed in the video did indeed rise slowly, but it wasn’t coming from inside the heating tube. Instead, it was generated from the surface of the quartz tube. Our carbon fiber heating tubes are packaged using PE bubble wrap, which is then placed in a wooden box. During the manufacturing process, the bubble wrap can leave a slight oily residue or other contaminants on the surface of the quartz tube. When the carbon fiber heating tube is powered on, the surface temperature of the tube can reach 500°C within just 10 seconds. Under such high temperatures, these substances evaporate, producing smoke. Typically, this phenomenon disappears after about two minutes of use. If there is any serious dirt or residue on the surface, we recommend gently wiping the tube with a soft cloth, as quartz heating tubes are more fragile compared to stainless steel heating tubes.

A Common Customer Question

Some knowledgeable customers may ask: “Is the surface smoke due to the quartz tube not being properly treated during production? Isn’t there an oil layer on the quartz tube during manufacturing? Are you cutting corners?”

I can assure you that all of the quartz tubes we use have undergone high-temperature treatment twice. They are durable and there’s absolutely no cutting of corners in our process. Even when exposed to cold water after being powered on, our heating tubes show no abnormalities. For more details, you can refer to our video on what happens when a 500°C quartz heating tube is splashed with water. Any of our heating tubes can pass this test.

Carbon Fiber Heating Tube Production Process

To further alleviate any concerns, I’ll share the production process of our carbon fiber heating tubes:

1. Cutting the Inner and Outer Tubes: The inner tube is a quartz glass tube that holds the carbon fiber heating filament. We first select the appropriate outer diameter, inner diameter, length, and quantity according to the order specifications, then proceed to cut the tubes.
2. Winding the Carbon Fiber Heating Filament
3. Carbon Fiber Heating Filament Processing: This step involves checking whether the heating filament’s parameters are within the standard range.
4. Installing the Electrodes
5. Spot Welding
6. Sealing
7. Vacuum Extraction
8. Aging Process
9. Attaching Wires and Installing Insulated Caps
10. Product Inspection and Shipping: The finished product is inspected for all parameters such as length, voltage, power, and wire length. Once all parameters meet the standards, the product is packaged and shipped.

This is our comprehensive process for producing carbon fiber heating tubes.

Our company specializes in producing high-quality carbon fiber heating tubes. For more information, visit our web stranica ili nam pošaljite e-poštu na contact@globalquartztube.com.