What sizes of fused quartz tube can VEZLO produce?

Standard transparent fused quartz tubes are produced from 2 mm to 500 mm outer diameter. A 520 mm large-diameter high-purity quartz tube has also been developed for semiconductor diffusion and oxidation furnaces. Wall thickness, length and end finishing are made to drawing.

What is the difference between fused quartz and fused silica?

Fused quartz is made by melting high-purity natural quartz crystal or sand, while synthetic fused silica is produced from silicon-based precursors such as SiCl4. Synthetic silica offers higher deep-UV transmission, while fused quartz provides excellent thermal stability and purity at a lower cost for lamps, furnaces, labware and most industrial uses.

What is an ozone-free quartz tube?

An ozone-free quartz tube is doped to absorb the 185 nm ultraviolet line that converts oxygen into ozone, while still transmitting the 254 nm germicidal wavelength. It is widely used for UV sterilization lamps in water, air and surface disinfection where ozone is not wanted.

Do you accept OEM and ODM custom quartz parts?

Yes. VEZLO manufactures to customer drawings, including tubes with closed or flared ends, ground joints, flanges, quartz boats, cleaning tanks, crucibles, plates, windows and rods, as well as private-label packaging.

How fast does VEZLO respond to technical requests?

The average response time is within 2 hours, and around 50% of buyers place repeat orders. Requirements can be sent to info@vezloquartz.com or via the contact page.

How are fragile quartz products packed for export?

Quartz parts are typically protected individually with foam or pearl cotton, then packed in reinforced cartons or fumigation-free plywood cases suitable for sea, air and express shipping.

CE Certified Quartz Glass Bar Factory & Exporters

Global Sourcing White Paper & Engineering Guide: Optical Fused Silica, High-Purity Solid Quartz Bars, Thermal-Shock Components, and Industrial CNC Machining.

≥ 99.99%

SiO₂ Chemical Purity

1100°C

Continuous Working Temp

≤ 2 Hours

Technical RFQ Response Time

50%

Direct Buyer Reorder Rate

Engineered Precision Portfolio

Featured Industrial Quartz & Silica Solutions

Direct from Donghai County, China's quartz capital. Every unit undergoes automated dimensional metrology, strain-free annealing, and rigorous thermal testing to meet CE and ISO standards.

Quartz Viewport Glass Quartz Window Plate Optical Window Quartz High Pressure

Quartz Plate for Boiler Sight Glass Fused Silica Heat Resistant

Quartz Glass Plate 0.5mm 1mm 2mm Thickness Fused Silica Clear Custom Size

Quartz Optical Flat Plate Fused Silica High Flatness Polished Custom

Quartz Oil Level Sight Glass Plate Fused Silica Clear Custom Size

CNC Machined Quartz Plate Fused Silica Complex Shape Custom Size

Rectangular Quartz Plate Fused Silica Clear Precision Cut Custom Size

Drilled Quartz Plate Multi Hole Fused Silica CNC Machined Custom

Manufacturing Authority

Enterprise Competence & Production Infrastructure

Operating from our 50-mu facility in Donghai County with RMB 10 million in fixed assets, we merge mineral refinement with advanced flame-working and CNC cold-grinding.

Provincial R&D Recognition

Our heavy-duty high-purity components for large-scale integrated circuits were developed under the Jiangsu Provincial Science & Technology Support Project. We reinvest over RMB 5 million annually in pure thermal fusion innovations, including proprietary 520 mm diameter furnace core processes.

Verified Supply Chain Rigor

As an onsite-verified manufacturer audited by independent third-party certifiers and Alibaba.com, our quality management system adheres strictly to CE compliance directives. We guarantee total metal impurities under 20 ppm on premium natural melts.

Full-Spectrum CNC Machining

From solid round bars (Ø1.5 mm to 80 mm) and precision rectangular slabs to multi-hole laser drilling and chamfered sight glasses, our high-precision CNC multi-axis centers achieve dimensional tolerances tighter than ±0.02 mm.

Technical Benchmarking

Material Performance & Specification Parameters

Fused quartz bars and plates offer mechanical stiffness, high dielectric insulation, and thermal endurance superior to standard borosilicate and aluminosilicate glasses.

Physical / Chemical Metric	Typical Value (JGS2 / Fused Quartz)	Synthetic Silica (JGS1 / Fused Silica)	Strategic Engineering Advantage
SiO₂ Content	≥ 99.99%	≥ 99.9999%	Eliminates batch contamination in semiconductor diffusion & optical stages.
Coefficient of Thermal Expansion	5.5 × 10⁻⁷ / °C (20°C–320°C)	5.2 × 10⁻⁷ / °C (20°C–320°C)	Virtually zero expansion under rapid cyclical heating from 20°C to 1100°C.
Softening & Anneal Points	1683°C (Softening) / 1215°C (Anneal)	1730°C (Softening) / 1180°C (Anneal)	Maintains structural integrity where borosilicate melts; ideal for furnace sight glasses.
Optical Transmission Window	260 nm – 2500 nm (Near UV - NIR)	185 nm – 2500 nm (Deep DUV - NIR)	Offers high transmission across broad spectral envelopes for laser viewports.
Dielectric Strength (20°C)	25–40 kV/mm	> 40 kV/mm	Superior electrical insulation for high-frequency microwave and plasma generation.

Market Intelligence

Procurement Dynamics & Future Quartz Glass Trends

Strategic global procurement teams are shifting how they source raw and machined quartz glass bars. Below are the key technological and macroeconomic drivers guiding B2B purchasing.

Sub-Nanometer Semiconductor Tooling

The acceleration of advanced packaging, extreme UV (EUV) photolithography, and atomic layer deposition (ALD) demands raw quartz glass bars with total trace elemental purity under < 10 ppm. Buyers are eliminating hydroxyl (OH) groups down to < 5 ppm to prevent optical absorption and bubble outgassing during high-energy wafer processing.

Near-Net-Shape Machining

Procurement teams are prioritizing factories capable of supplying near-net-shape bars, discs, and pre-drilled plates. Direct CNC waterjet profiling and laser micro-drilling eliminate diamond tool wear on the buyer's end, shrinking assembly lead times and mitigating chipping risks on critical sight ports.

Green Photovoltaics & Fusion Energy

Next-generation TOPCon and Perovskite solar cells require wider, thicker quartz carrier rods and reaction plates to handle continuous furnace thermal runs. Experimental tokamak optical diagnostic windows are driving higher demand for strain-free, bubble-grade Class 0 fused silica viewports that resist neutron irradiation.

Procurement Knowledge Base

Frequently Asked Technical Questions

Actionable answers to help engineering and sourcing professionals verify technical drawings, material purity, and compliance certificates.

How do fused quartz bars differ from synthetic fused silica bars?

Fused quartz bars are melted from high-grade natural crystalline quartz sand (SiO₂ ≥ 99.99%). They provide high thermal shock resistance and lower cost for high-temperature furnace sight glasses and industrial viewports. Synthetic fused silica is produced via chemical vapor deposition (CVD) of SiCl₄ (SiO₂ ≥ 99.9999%), offering deep ultraviolet transmittance down to 185 nm without bubble inclusions.

What surface roughness and optical flatness tolerances can you achieve?

For optical windows, sight glasses, and plates, our double-sided planetary polishing centers routinely deliver surface figures of λ/4 to λ/10 per inch @ 632.8 nm. Surface roughness can be held to Ra < 0.5 nm (super-polished), with scratch-dig standards conforming to MIL-PRF-13830B (20-10 or 40-20 optical grade).

How does CE certification apply to industrial quartz bars and plates?

CE compliance for quartz sight glasses and pressure viewports is governed primarily under the Pressure Equipment Directive (PED 2014/68/EU) and relevant optical-machinery safety directives. We verify maximum allowable working pressure (MAWP) with hydraulic proof testing, thermal-strain birefringence analysis, and full material test reports (MTR).

What is the standard protective packaging protocol for export shipments?

To prevent transit fractures and static dust adhesion, every quartz piece is individually wrapped in dust-free film or pearl cotton, cushioned with high-density EPE molded foam inserts, and placed into reinforced corrugated boxes or fumigation-free wooden crates suitable for global air and ocean freight.

Connect with Certified Quartz Sourcing Engineers

Submit your 2D/3D CAD drawings (DWG, STEP, PDF) or technical specifications. Our application engineers review thermal requirements, mechanical tolerances, and optical spectra to provide a detailed quote within two hours.