Explore our top-tier fused silica quartz products engineered for extreme thermal endurance, vacuum-tight sealing, and aggressive chemical processing environments.
Precision fused quartz (amorphous silicon dioxide) test tubes represent the pinnacle of vitreous chemistry ware, delivering mechanical, optical, and thermal endurance impossible with borosilicate 3.3 or aluminosilicate glass.
In analytical laboratories, semiconductor foundries, and photochemical reactors, the term clear silica quartz test tube refers specifically to vessels synthesized from electric arc fusion or oxy-hydrogen gas fusion of ultra-pure natural quartz sands or synthetic silicon precursors (SiCl&sub4;). The resulting material features a silica content exceeding 99.99% (4N) up to 99.999% (5N5). Unlike regular laboratory glassware compounded with fluxes such as sodium oxide (Na&sub2;O) and boric oxide (B&sub2;O&sub3;), pure fused silica displays an uninterrupted, tetrahedral [SiO&sub4;] network with exceptional bond energy (approx. 460 kJ/mol).
Hydroxyl (-OH) radical content is an essential metric in high-temperature and spectroscopic applications. Standard fused quartz tubes contain trace hydroxyl levels ranging from 15 ppm to 180 ppm depending on whether they are vacuum electric-melted or flame-melted. In contrast, our specialized dry synthetic quartz varieties reduce OH content to below < 5 ppm. Eliminating OH absorption bands around 1.38 μm, 2.2 μm, and 2.72 μm prevents premature structural devitrification (crystallization to cristobalite) when operating continuously between 1,050°C and 1,200°C.
With a strain point at 1,070°C, an annealing point at 1,180°C, and a softening threshold approaching 1,683°C, these tubes endure continuous soaking at 1,100°C and transient peak cycles up to 1,300°C.
A minute coefficient of thermal expansion (α ≈ 5.5 × 10−7 / K between 20°C and 1,000°C) enables instant quench testing: heating red-hot to 1,150°C followed by immediate submersion into ice water without micro-fractures.
Optical transmission extends from the deep ultraviolet (DUV cutoff ∼190 nm) across visible wavelengths (transmittance >92%) into the near-infrared spectrum, optimizing tubes for spectrophotometry, UV-C curing, and photolysis.
Impervious to almost all inorganic and organic acids—including hot concentrated sulfuric (H&sub2;SO&sub4;), nitric (HNO&sub3;), and hydrochloric (HCl) acids—except hydrofluoric (HF) and hot phosphoric (H&sub3;PO&sub4; > 150°C).
Located in Donghai County, Jiangsu Province—recognized globally as China's premier hub for raw crystal refining and quartz manufacturing—Southeast Quartz bridges high-grade mineral assets with advanced hot-working engineering.
Direct vertical integration with local beneficiation plants enables uninterrupted procurement of low-iron, high-purity natural silica sand. Trace metallic impurities such as Fe, Al, Cu, Na, and Li are suppressed at the leaching stage, insulating international OEM clients from raw-material supply shocks and price volatility.
Our facility couples specialized glass-blowing lathes, continuous drawing towers, and oxy-hydrogen fusion torches with multi-axis CNC ultrasound cutting, edge beveling, centerless grinding, and laser profile verification under one manufacturing roof for single-source quality control.
By leveraging local specialized tooling vendors and precision gas distribution networks, Southeast Quartz completes prototype samples within 48 to 72 hours of drawing sign-off, reducing turnkey lead times for custom flanged, threaded, or round/flat bottom tubes by 30% to 50% compared to Western manufacturers.
| Performance Parameter | High-Purity Natural Quartz (Grade SQ-1) | Semiconductor Electric Fused (Grade SQ-SEMI) | Synthetic Fused Silica (Grade SQ-SYN) | Standard Borosilicate 3.3 (Comparative) |
|---|---|---|---|---|
| SiO&sub2; Purity Matrix | ≥ 99.99% | ≥ 99.998% | ≥ 99.9999% (6N) | ≈ 81.0% (SiO&sub2; + B&sub2;O&sub3;) |
| Hydroxyl (-OH) Concentration | ≤ 120 ppm | ≤ 20 - 30 ppm | ≤ 5 ppm (Dry Grade) | Not Applicable (Fluxed Glass) |
| Max Working Temperature (Long Term) | 1,050°C | 1,150°C | 1,200°C | 490°C |
| Softening Point | 1,665°C | 1,683°C | 1,730°C | 825°C |
| Thermal Expansion (0-300°C) | 5.5 × 10−7 K−1 | 5.4 × 10−7 K−1 | 5.2 × 10−7 K−1 | 33 × 10−7 K−1 |
| UV Cutoff Wavelength (λ) | ≈ 220 nm | ≈ 205 nm | ≈ 185 nm (DUV VUV) | ≈ 310 nm (Opaque to UV) |
| Trace Fe + Cu + Al Impurity | < 15 ppm total | < 6 ppm total | < 0.1 ppm total | > 2,000 ppm composite |
Industrial supply chain directors, procurement officers, and lead process engineers require uncompromising lot consistency, verifiable certification, and rigid adherence to mechanical blueprints.
Purchasing quartz test tubes for analytical carousels, automatic sample handlers, or plasma torch injectors demands micrometer precision. A slight eccentricity or wall-thickness variation creates stress points under thermal load, leading to unpredicted tube failure. Southeast Quartz fulfills rigorous procurement criteria:
We accept native CAD/CAM files (.STEP, .IGES, .DWG, .DXF, or PDF drawings), providing rapid Design for Manufacturability (DFM) reviews to catch stress raisers and reduce hot-working cycle times.
Each shipment includes comprehensive Certificates of Analysis showing ICP-MS trace metal analysis, optical transmission curves, and helium leak inspection compliance documentation.
Flexible Incoterms (EXW, FOB, CIF, DDP) supported by sea freight containers, expedited air transport, or international express courier with pre-cleared customs formalities for European and American ports.
We offer warehouse inventory reservation agreements for high-volume enterprise buyers, providing just-in-time (JIT) releases to buffer unexpected production surges or research spikes.
From cleanroom semiconductor processing chambers to pharmaceutical analytical labs, clear silica quartz test tubes serve critical functions where failure is not an option.
Utilized as mini-reaction sample tubes, gas sampling ampoules, and precursor bubbler vessels in chemical vapor deposition (CVD), atomic layer deposition (ALD), and diffusion furnaces. Low metal outgassing preserves minority carrier lifetimes.
With exceptional ultraviolet transparency (>90% at 254 nm UV-C germicidal and 185 nm ozone generation lines), these tubes serve as immersion well sleeves, photolysis digest cells, and standard fluorometry collection vials.
Standard containers for aqua regia digestions, Kjeldahl nitrogen determination, and pressurized microwave digestion of trace metals where borosilicate glass would leach boron, sodium, or silicon contaminants into the analyte.
Ideal for high-temperature flash pyrolysis of carbon polymers, differential thermal analysis (DTA) sample holders, and sealed vacuum-ampoule melting of specialized rare-earth alloys and chalcogenide glasses up to 1,200°C.
International customers receive comprehensive risk-mitigation guarantees spanning environmental directives, clean room compliance, and real-time engineering consults.
Our fabrication protocols comply with SEMI standards for quartzware dimensional tolerances and surface cleanliness (SEMI C31 and C10 guidelines), backed by an ISO 9001:2015 quality management framework.
All clear quartz products are non-toxic, chemically inert, and 100% compliant with EU RoHS (Directive 2011/65/EU) and REACH (EC 1907/2006) regulations, containing zero heavy metals, lead, mercury, cadmium, or SVHC substances.
Our bilingual optical and materials engineering team provides active technical coverage during North American and European business hours, providing DFM feedback, quotation turnaround, and CAD revisions within 24 hours.
Material innovations are accelerating to keep pace with advanced lithography, photonic computing, and next-generation green energy technologies.
As semiconductor wafer fabrication nodes shrink below 3 nm and extreme ultraviolet (EUV) source optics become widespread, the demand profile for clear silica quartz test tubes and reaction vessels is shifting radically:
Get precise technical answers regarding material selection, thermal limitations, cleaning protocols, and bespoke OEM ordering.
Select from our specialized semiconductor boats, precision rods, and optical plates designed to withstand the most demanding thermal processes.
