Our high-purity quartz blocks are specifically engineered as essential tools for the precise heat sealing of 20mm outer diameter tubes. Crafted from inert fused silica, these blocks fit securely into tube indentations, providing crucial internal support that facilitates a uniform, robust, and contamination-free seal. Ideal for critical applications requiring vacuum encapsulation, sample preservation, or sealing of high-purity materials at elevated temperatures, these quartz blocks ensure superior results where traditional sealing methods fall short. Custom dimensions are available for various tube sizes and sealing requirements.

Remarks:
- ayment method: By wire transfer or advance payment, depending on the quantity of the order.
- Delivery time: According to the order quantity.
- Transportation method: Sea freight or air freight, depending on the customer.
| Property Content | Property Values |
|---|---|
| SiO2 | 99.99% |
| Density | 2.2×10³ kg/cm³ |
| Hardness | 5.5 - 6.5 Mohs' Scale 570 KHN 100 |
| Tensile Strength | 4.8×10⁷ Pa (N/mm2) (7000 psi) |
| Compression Strength | >1.1×10⁹ Pa (160,000 psi) |
| Coefficient of Thermal Expansion | 5.5×10⁻⁷ cm/cm·°C (20°C-320°C) |
| Thermal Conductivity | 1.4 W/m·°C |
| Specific Heat | 670 J/kg·°C |
| Softening Point | 1730°C (3146°F) |
| Annealing Point | 1210°C (2210°F) |
| Strain Point | 1120°C (2048°F) |
| Work Temperature | 1200°C (2192°F) |
| Electrical Resistivity | 7×10⁷ ohm cm (350°C) |
| Size | Customized |
| Logo | Customized Logo Accept |
Enables Precise & Uniform Heat Sealing
This quartz block provides crucial internal support within the tube during the heat sealing process, preventing deformation and ensuring a consistent, symmetrical, and robust seal, which is vital for maintaining vacuum or inert atmospheres.
High Purity & Non-Contaminating
Made from ultra-high purity fused silica, the block itself is inert and will not introduce impurities into the sealed tube’s contents, making it indispensable for encapsulating sensitive samples or high-purity materials.
Excellent High-Temperature Stability
Quartz’s inherent thermal stability allows this block to withstand the extreme temperatures required for heat sealing glass or quartz tubes without melting, deforming, or reacting, ensuring reliable and repeatable sealing operations.
Optimized for Specific Tube Sizes & Customization
Designed to perfectly fit 20mm outer diameter tubes (and other specific tube dimensions with customization), these blocks provide a tailored solution that maximizes sealing efficiency and quality. Full customization is available for various tube diameters and sealing needs.
Application Scenario
High-Purity Sample Encapsulation
Essential for heat-sealing glass or quartz ampoules and tubes containing sensitive or high-purity chemical samples (e.g., reagents, standards, research compounds) where preventing contamination and maintaining an inert or vacuum environment is critical for long-term storage or analysis.
Material Synthesis & Processing in Sealed Tubes
Employed in material science and chemistry for sealing small-scale reaction tubes where materials are synthesized or processed under high temperatures and specific atmospheres (e.g., solid-state reactions, crystal growth, thermal decomposition in a sealed environment).
Handle with care
Quartz glass products are made from valuable materials and must be handled gently to avoid collisions and falls.
Regular maintenance
The maintenance of quartz tubes must be performed regularly to ensure their long-term stable performance. Regularly check the connections, fixings, and mechanical vibrations of the quartz tubes to prevent abnormalities. The exterior of the quartz tubes is prone to contamination from dust and moisture, so they should be cleaned regularly.
Storage environmen
When storing quartz tubes, care should be taken to avoid exposure to mechanical vibrations, shocks, and excessively high temperatures. They should be kept in a dry, cool, and well-ventilated place, avoiding direct sunlight and high-temperature environments.
Yes, the quartz block is highly reusable. Crafted from durable fused silica, it is designed to withstand repeated exposure to the high temperatures required for heat sealing without degradation, deformation, or contamination. Its robust nature ensures a long service life, making it a cost-effective tool for ongoing sealing needs.
Yes, while specifically designed for quartz tubes due to material compatibility and thermal expansion, this quartz block can also be effectively used for heat sealing borosilicate glass tubes of compatible dimensions. Its function is to provide internal support, which is beneficial for sealing various types of glass tubing that require a precise and uniform closure.
Yes, absolutely. While the product example specifies a block for 20mm OD tubes, we offer custom fabrication for quartz blocks in various dimensions and shapes to perfectly match different tube outer diameters and internal configurations. If you require a block for a tube size other than the standard offerings, please provide your specifications for a tailored solution.
Frequently asked questions
We specialize in the end-to-end manufacturing of high-purity quartz glass components. Our core product lines include:
Quartz Tubing & Rods: A wide range of diameters and specifications.
Quartz Plates & Discs: Precision-cut and polished for optical and industrial use.
Quartz Labware: A full suite of standard and custom glassware, including beakers, flasks, and boats.
Semiconductor-Grade Quartz: High-purity components like process tubes and carriers for semiconductor fabrication.
Custom Fabricated Components: We can produce complex parts tailored to your unique designs and specifications.
Yes. Custom fabrication is at the core of our business. With over a decade of specialized experience, we partner with companies to provide expert OEM/ODM services. Our capabilities include welding, grinding, drilling, polishing, bending, and other precision processing techniques to create components that meet your exact requirements.
Quality is paramount in our manufacturing process. We are an ISO 9001:2015 certified manufacturer, ensuring that our processes meet international quality management standards.Our products also undergo rigorous SGS testing for purity and performance. We use high-purity raw materials (up to 99.998% SiO2) to produce fused quartz and fused silica products with exceptional thermal stability, high-temperature resistance, and chemical inertness.
We've streamlined our process to be as efficient as possible:
Submit Your RFQ: Send us your technical drawings, specifications, and requirements via our website contact form or email.
Rapid Response: You can expect an initial response within minutes and detailed communication within half an hour.
Design & Proposal: We will deliver a detailed design proposal and a competitive quote within 24 hours.
Prototyping & Production: Upon approval, we move swiftly from prototyping to full-scale production to meet your deadlines.
Partnering with Aoxin Quartz offers several key advantages:
Proven Expertise: With 10+ years in the industry, we have the technical knowledge to tackle complex challenges.
One-Stop Solution: We manage the entire production process, from sourcing high-purity raw materials to fabricating and finishing complex components.
Competitive Value: Located in a major quartz production hub, we leverage an efficient supply chain and advanced manufacturing to offer exceptional quality at a competitive price point.
Dedicated Partnership: Over 90% of our clients become long-term partners. We are committed to your success through responsive service, reliable quality, and innovative solutions.
























