Quartz tubes for chemical process furnaces are high-purity quartz glass tubes specifically designed for high-temperature chemical reaction environments. Made from fused quartz with a silicon dioxide content of at least 99.5%, they possess excellent thermal stability, chemical inertness, and electrical insulation properties. In chemical production, these tubes serve critical roles as reaction chambers, media transport channels, and thermal protection sleeves. They can withstand temperatures exceeding 1,200°C and highly corrosive environments involving strong acids, while maintaining an extremely low coefficient of thermal expansion, making them resistant to cracking under rapid cooling and heating conditions. For chemical furnace systems involving halide heating, the synthesis of high-purity materials, or the handling of corrosive media, quartz tubes are often the core components that ensure process purity and the long-term, stable operation of equipment.

In the process of chemical production, furnaces are key heating equipment widely used in chemical reactions, material sintering, high-temperature treatment and other processes. Quartz tube, as a high-performance high-temperature and corrosion-resistant material, plays an important role in chemical furnaces and kilns.

Physical and chemical properties of quartz tube

The main component of quartz tube is high-purity silicon dioxide (SiO ₂), which has the following excellent characteristics:

-High temperature resistance: The softening point can reach up to 1700 ℃, and the long-term use temperature can reach over 1200 ℃, suitable for high-temperature furnace environments.

-Thermal stability: The coefficient of thermal expansion is extremely low (about 5.5 × 10 ⁻⁷/℃), and it can withstand drastic temperature changes without easily exploding.

-Chemical inertness: Acid resistant (except hydrofluoric acid and hot phosphoric acid), solvent resistant, corrosion-resistant, suitable for highly corrosive chemical environments.

-High transparency: The ultraviolet infrared band has good transparency and can be used for optical heating and observation of reaction processes.

-Electrical insulation: high dielectric strength, suitable for insulation protection of electric heating furnaces.

These characteristics make quartz tubes an indispensable key component in chemical furnaces.

The specific role of quartz tubes in chemical furnaces and kilns

As a reaction chamber

Quartz tubes are commonly used in reaction chambers of chemical furnaces to provide a closed or semi closed reaction environment, suitable for:

-Vapor Deposition (CVD): Preparation of semiconductor materials and graphene.

-High temperature sintering: sintering of materials such as ceramics and powder metallurgy.

-Chemical synthesis: such as melting high-purity silicon and special glass.

Due to the high chemical purity of quartz tubes, metal contamination can be avoided, ensuring the purity of reaction products.

As a protective tube

In high-temperature furnaces, quartz tubes are commonly used to protect key components such as thermocouples and heating elements

-Thermocouple protection: prevents thermocouples from being corroded by corrosive gases and improves temperature measurement accuracy.

-Heating wire isolation: In a resistance furnace, quartz tubes can wrap the heating wire to prevent oxidation and short circuits.

As an observation window

Due to its excellent transparency, quartz tubes can be used for:

-Reaction process monitoring: Observe the reaction status inside the furnace through quartz window, such as flame and melting conditions.

-UV/infrared heating: Combined with specific light sources (such as UV lamps, infrared heaters) for photochemical reactions.

As a gas guide tube

In chemical furnaces, quartz tubes can be used for:

-Inert gas protection: In environments such as nitrogen and argon, quartz tubes can guide gas flow to prevent sample oxidation.

-Corrosive gas transportation: tubelines for transporting highly corrosive gases such as chlorine and hydrogen fluoride.

As an insulation and support structure

Quartz tubes have excellent electrical insulation properties and can be used for:

-High temperature insulation: used as an electrode support in an electric furnace to prevent current leakage.

-Sample bracket: Support the sample in a high-temperature environment to avoid contamination caused by metal brackets.

Selection and usage precautions of quartz tube

Key selection points

-Temperature range: Select the appropriate model based on the maximum temperature of the furnace (ordinary quartz tube can withstand 1200 ℃, high-purity quartz tube can withstand above 1600 ℃).

-Size matching: The inner diameter and wall thickness should comply with the furnace design to avoid thermal stress concentration.

-Surface treatment: Matte quartz tube can reduce light reflection and improve heating uniformity.

Precautions for use

-Avoid mechanical impact: Quartz tubes have high brittleness, so be careful during installation.

-Preventing fluoride corrosion: Hydrofluoric acid and fluoride gas can severely corrode quartz tubes, so contact should be avoided.

-Slow temperature rise and fall: Rapid temperature changes may cause cracking, it is recommended to increase the temperature rate by ≤ 10 ℃/min.

Quartz tubes play an irreplaceable role in chemical furnaces, mainly reflected in:

1. Provide a high-temperature and corrosion-resistant reaction environment.

2. Protect critical components such as thermocouples and heating wires from corrosion.

3. As an observation window and gas guide channel.

4. Ensure high-purity reaction conditions and avoid metal contamination.

Frequently Asked Questions (FAQ)

What is the maximum temperature that quartz tubes for chemical process furnaces can withstand?

Our quartz tubes can operate stably for extended periods at 1100°C and can withstand temperatures up to 1450°C for short periods, meeting the requirements of the vast majority of high-temperature chemical processes.

Are quartz tubes resistant to acid and alkali corrosion?

Yes, high-purity quartz exhibits exceptional resistance to most acids (except hydrofluoric acid); however, caution is advised when using it in strong alkaline environments. We recommend consulting our technical team for specific operating conditions.

Can special sizes or shapes be customized?

Absolutely. We offer comprehensive customization services, including outer diameter, wall thickness, length, and special-shaped processing (such as flanges, elbows, and perforations). We can manufacture products based on your drawings.

Proper selection and use of quartz tubes can significantly improve the stability, safety, and production efficiency of chemical furnaces.

Luverre Quartz is a manufacturer specializing in quartz tubes and other quartz items.We have over 18 years experience with the production of quartz tubes, we will be your reliable partner on quartz tubes and other quartz items.

Luverre Quartz can manufacture customized quartz tubes in various shapes, such as spiral, square, round, with processing including cutting, bending, welding, etc., and available in different colors, such as transparent quartz tubes, opaque quartz tubes, milky white quartz tubes, red quartz tubes, and so on.