High-Purity Fused Quartz Components & Process Tubes
Manufactured from ultra-pure natural crystalline silica from Donghai, Jiangsu. Continuous electric fusion, gas flame purification, and precision grinding deliver SiO₂ purity up to 99.999% with ultra-low OH- radical concentration.
99.99% Pure Clear Quartz Twin Tube Polished Ozone Free
Precision dual-bore geometry customized for industrial infrared heating modules and acid-resistant chemical pipelines.
- Purity (SiO₂)≥ 99.99%
- Max Temp (Short)1450 °C
- ProcessingBending / Flanging
High Purity Clear Fused Quartz Glass Tube Flat Cut
Standard furnace process tubes with tight dimensional OD/WT concentricity tolerance and stress-relieved annealed ends.
- Diameter RangeOD 2mm – 450mm
- Continuous Temp1100 °C
- End ProfileFlat Unpolished / Polished
Optical Fused-Quartz Cuvettes with PTFE Lids
Optical precision fused quartz cells ensuring >80% spectral transmission in the 190nm–2500nm deep ultraviolet band.
- Spectral Range190 – 2500 nm
- Path Length10 mm Standard
- ClosureCorrosion PTFE Lid
Clear Fused-Quartz Beakers with Spout
Heavy-wall fused quartz labware resistant to thermal quenching from 1100 °C into cold water without structural fatigue.
- Acid ResistanceTotal (Except HF)
- Thermal Expansion5.5 × 10⁻⁷ /°C
- Capacities25ml – 5000ml
Precision Optical Square Quartz Plates with Chamfer
Double-sided precision lapping and polishing (Ra < 0.5nm) for semiconductor photomasks and laser viewports.
- Surface Figureλ/4 or λ/10
- Parallelism< 20 arcsec
- Edge TreatmentCNC 45° Chamfer
Fused-Quartz Petri Dishes with Ground Lids
Ultra-clean, heavy-duty quartz vessels designed for acid evaporation, vacuum thermal ash drying, and cleanroom culture.
- ContaminationZero Metallic Leaching
- Operating Range-40 °C to 1200 °C
- FinishFire Polished / Ground
10 Inch Opaque Milky Fused Quartz Crucible
Micro-bubble dispersion design offering exceptional infrared thermal shielding during monocrystalline silicon and noble metal casting.
- Density≥ 2.18 g/cm³
- Softening Point1683 °C
- StructureOpaque Bubble Shield
Polished Clear Fused Silica Quartz Glass Rods
Solid quartz bars tailored for fiber preform support, light guiding waveguides, furnace pushers, and high-temp apparatus fixtures.
- DiametersØ 4mm – 42mm
- Refractive Index1.4585 (589 nm)
- Straightness≤ 0.5 mm/m
Thermodynamic & Structural Superiority of Fused Quartz Glass
Fused quartz represents the apex of amorphous silica engineering. Unlike multi-component borosilicate or soda-lime glasses, vitreous silica consists strictly of bonded silicon-oxygen tetrahedra (SiO₄) forming a continuous, randomized three-dimensional network. This cross-linked bond energy imparts an extraordinarily low coefficient of thermal expansion (α = 5.5 × 10⁻⁷ K⁻¹ between 20 °C and 320 °C), granting the material immunity against violent thermal shock.
Kemzo Quartz sources its raw feedstock from the crystalline quartz geological deposits of Donghai County, China. Through specialized chemical beneficiation, electrostatic separation, and high-temperature vacuum dehydroxylation, metallic impurities (Fe, Al, Ti, alkali metals) are suppressed below critical parts-per-billion (ppb) thresholds, preventing high-temperature crystallization into cristobalite.
Real-time laser diameter control maintains outer wall concentricity within ±0.15mm across 3000mm tube runs.
Fused Quartz Physical, Thermal & Dielectric Specifications
Comparative technical metrics illustrating the mechanical endurance and thermal envelope of Donghai Kemzo precision fused quartz tubes.
| Physical / Mechanical Property | Test Standard / Condition | Kemzo Fused Quartz Value | Technical Significance in Industrial Service |
|---|---|---|---|
| Density (ρ) | Room Temp (20 °C) | 2.20 × 10³ kg/m³ | Lightweight mechanical stability for large semiconductor furnace tubes. |
| Coefficient of Thermal Expansion | 20 °C – 300 °C | 5.5 × 10⁻⁷ / °C | Negligible dimensional change during rapid thermal ramp cycles (>50 °C/min). |
| Transformation Point (Tg) | DIN 52324 | 1075 °C | Transition envelope between brittle viscoelastic and elastic behavior. |
| Continuous Operating Temp | Neutral Atmosphere | 1100 °C – 1150 °C | Standard threshold for long-term CVD, oxidation, and diffusion processes. |
| Short-Term Max Operating Temp | Isothermal Exposure | 1450 °C | Emergency peak resistance without catastrophic plastic tube sagging. |
| Young's Modulus of Elasticity | 20 °C, Ultrasonic resonance | 7.2 × 10⁴ MPa | High rigidity resisting mechanical deflection in vertical wafer carrier boats. |
| Dielectric Strength (E) | 20 °C, 1 MHz frequency | 2.5 × 10⁷ V/m – 3.0 × 10⁷ V/m | Superior high-voltage electrical insulation for plasma etching reactors. |
| Hydroxyl (OH⁻) Concentration | FTIR Infrared Absorption | < 15 ppm (Standard) / < 2 ppm (Baking) | Low OH prevents premature bubble expansion and reduces high-temp devitrification. |
Enterprise Strengths & Vertical Supply Chain Dominance
Based in the epicenter of the Chinese quartz capital since 2011, Kemzo Quartz combines raw resource purity with precision European CNC cutting, computerized flame lathe working, and full ISO 9001 certified batch traceability.
Donghai Epicenter Raw Feedstock
We exercise primary control over mining beneficiation and quartz purification in Donghai, Jiangsu. Direct access to raw high-purity crystalline quartz ensures zero reliance on spot trading, yielding rock-solid price stability, predictable lead times, and uncompromised SiO₂ batch consistency.
Advanced 10+ Line Thermal Extrusion
Kemzo operates continuous thermal fusion drawing lines equipped with automated multi-axis optical wall thickness scanners. We maintain tight tube tolerances (±0.10mm on OD/ID, ≤1.0mm/m bow straightness), eradicating mechanical fitting stress during furnace flange couplings.
11+ Years Full Drawing OEM / ODM
Our master glassblowers and 5-axis CNC ultrasonic grinding centers execute sophisticated custom components directly from customer CAD drawings (STEP, DWG, PDF). From ground-taper gas ports to complex welded manifold spirals, tolerances meet semiconductor-grade criteria.
Vacuum Annealing & Stress Relief
Every fabricated component undergoes computer-programmed electric furnace annealing at 1215 °C followed by controlled cooling through the strain point (1120 °C). Cross-polarized optical inspection guarantees zero residual hoop stress, preventing sudden thermal cracking.
ISO 9001 & High-Tech Enterprise
Awarded official Jiangsu High Technology Enterprise standing, our factory operates an uncompromising quality assurance management system. Every production batch is backed by comprehensive CoA reports detailing GDMS trace elemental impurity spectrums.
Export Protocol & Breakage Guarantee
Exporting 75%+ of our production to North America, Europe, Japan, and Korea, we employ triple-density shockproof foam suspension cradles within multi-layer fumigated timber crates. We guarantee 100% replacement compensation for any transit damage.
Future Trends in Fused Quartz Industrial Procurement
Procurement directors and fab managers face a rapidly shifting macro landscape across 2025–2030. Here is how advanced manufacturing sectors are recalibrating their fused silica supply strategies.
Total Cost of Ownership (TCO) Shift
Buyers are transitioning away from low-bid unit pricing toward calculated Lifetime Thermal Value (LTV). Premium fused quartz with OH- values under 10 ppm resists devitrification sagging up to 40% longer in LPCVD reactors, directly minimizing fab downtime during wafer changeouts.
Semiconductor Fab Scaling (300mm/450mm)
Advanced sub-3nm chip fabrication nodes enforce extreme requirements on large-bore quartz tubes (OD > 350mm). Buyers now demand GDMS testing certifying metallic impurities like copper (Cu) and iron (Fe) below 0.1 ppb to preserve ultra-clean silicon gate dielectric layers.
Photovoltaic TOPCon Cell Expansion
The global upgrade from PERC to n-type TOPCon solar architectures has escalated continuous boron and phosphorus diffusion furnace temperatures beyond 1150 °C. High-purity quartz diffusion tubes and slotted boats have become strategic bottlenecks requiring long-term supply volume agreements.
Direct-from-Source Procurement
Global supply chain fragility has prompted European and US industrial enterprises to bypass third-party trading intermediaries. Engaging directly with source-integrated Chinese manufacturers like Kemzo in Donghai cuts markups by 25–35% while granting direct engineering line oversight.
Technological Evolution in Vitreous Silica Processing
The transition from manual oxy-hydrogen torch lathe synthesis to closed-loop CNC plasma fusion represents a transformative leap in quartz processing. Modern semiconductor process chambers enforce dimensional tolerances on diameter, ovality, and wall thickness within micro-scale variations (±0.05 mm).
Furthermore, the advent of vacuum electrical melting has reduced the hydroxyl (OH⁻) content in finished quartz tubes from 150–200 ppm down to single-digit fractions (≤ 5 ppm). This structural dehydroxylation elevates the softening point by nearly 80 °C, dramatically mitigating viscous creep deformation when the tubes run at continuous high-temperature plateaus of 1200 °C in atomic layer deposition (ALD) and rapid thermal annealing (RTA) equipment.
Kemzo integrates laser interferometer surface characterization and automated chemical vapor polishing, providing an optical surface roughness of Ra ≤ 0.2 nm across optical windows, cuvettes, and high-pressure level sight gauges.
High-purity quartz tubing undergoes computer-controlled flame finishing and optical stress polariscopic validation.
Trace Chemical Element Analysis (ICP-MS Certified PPM)
Typical maximum impurity concentrations in Kemzo high-purity clear fused quartz tubes, ensuring absolute cleanliness in thermal furnaces.
| Trace Impurity Element | Chemical Symbol | Kemzo Semiconductor Grade (PPM) | Kemzo Optical / Solar Grade (PPM) | Process Contamination Risk Avoided |
|---|---|---|---|---|
| Aluminium | Al | 8.0 – 14.0 | 16.0 – 22.0 | High concentrations lower the devitrification onset temperature. |
| Iron | Fe | 0.08 – 0.20 | 0.25 – 0.60 | Transition metal generating unwanted absorption bands in the UV spectrum. |
| Titanium | Ti | 0.80 – 1.10 | 1.50 – 2.20 | Reduces optical transmission efficiency at deep UV wavelengths. |
| Calcium | Ca | 0.40 – 0.80 | 0.90 – 1.50 | Alkaline-earth metal accelerating nucleation of high-temp cristobalite crystals. |
| Sodium & Potassium | Na + K | 0.50 – 1.00 | 1.20 – 2.50 | Mobile ions that migrate across gate oxides, causing catastrophic MOS device threshold shift. |
| Copper | Cu | < 0.01 | < 0.05 | Deep-level contaminant fatal to minority carrier lifetime in silicon wafers. |
| Hydroxyl Radical | OH⁻ | ≤ 5 (Dehydroxylated) | ≤ 20 (Standard) | Excess OH causes bubble formation and structural plastic deformation at high temperatures. |
Frequently Asked Questions by Industrial B2B Buyers
Comprehensive technical and commercial answers addressing common engineering queries before purchasing fused quartz from China.
Q: What is the fundamental difference between fused quartz and fused silica?
Fused quartz is melted from naturally occurring, highly purified crystalline quartz (such as the geological deposits found in Donghai). It provides superior high-temperature mechanical creep resistance and cost-efficiency for furnace tubes, infrared heating, and semiconductor diffusion. Fused silica is synthetically generated from chemical precursors (such as SiCl₄ vapor). While synthetic fused silica offers higher transmission in the deep DUV spectrum (193 nm), natural fused quartz delivers higher thermal stability, lower sagging at 1200 °C, and approximately 40–60% lower material cost.
Q: What precise continuous and peak temperatures can your quartz tubes handle?
Kemzo clear fused quartz tubes sustain continuous operation at 1100 °C to 1150 °C under atmospheric or vacuum conditions. Short-term peak thermal spikes can safely reach 1450 °C. The material softening point sits at 1683 °C, while the annealing point is 1215 °C. Thanks to the near-zero thermal expansion coefficient (α = 5.5 × 10⁻⁷ / °C), a tube glowing red at 1100 °C can be dropped directly into 20 °C water without shattering.
Q: How do you prevent devitrification (whitening / cristobalite crystallization)?
Devitrification occurs when amorphous vitreous silica transforms into crystalline cristobalite at temperatures above 1150 °C, usually catalyzed by surface alkali contamination (fingerprints, sodium, dust) or excessive internal OH- content. We combat this by implementing ultra-clean hot deionized water ultrasonic etching, high-purity raw quartz processing, and offering optional vacuum dehydroxylation baking that drives internal OH- content down below 5 ppm.
Q: What custom mechanical tolerances can your Donghai factory achieve from drawings?
For tubular products, standard outer diameter (OD) and inner diameter (ID) tolerances are held within ±0.10 mm to ±0.25 mm depending on cross-section scale, with wall thickness concentricity variation ≤ 8%. For optical quartz plates, spectrophotometer cuvettes, and CNC-milled quartz blocks, our lapping and polishing lines deliver surface flatnesses to λ/4 (λ = 632.8 nm), parallelism < 15 arcseconds, and dimensional cut tolerances down to ±0.02 mm.
Q: How do you package delicate, oversized quartz process tubes for international freight?
Every individual quartz tube is sealed in cleanroom PE sleeves, wrapped in thick shock-absorbing EPE closed-cell foam, and secured inside corrugated individual cylindrical conduits. These assemblies are nestled into custom heavy-plywood maritime crates equipped with corner shock absorbers and moisture-desiccant packs. Outer crates feature international tilt and shock-drop impact sensors (Tip-N-Tell / Drop-N-Tell) for immediate transit auditing.
Q: What Incoterms, currencies, and turnaround times do you accommodate?
We support standard international commercial terms including EXW, FOB Qingdao/Shanghai, CFR, CIF, DDP, and DDU. Accepted settlement currencies include USD, EUR, AUD, HKD, and CNY via T/T wire transfer or irrevocable L/C at sight. Standard stock catalog tubes ship within 3–5 business days. Custom CAD drawing fabrications typically require 10–18 days from engineering signoff through flame processing, stress annealing, and final CMM inspection.
Request Technical Quotation & 2025 Fused Quartz Engineering Handbook
Submit your CAD drawings (.STEP, .DWG, .PDF) or custom dimensional schedules. Our Donghai factory engineering team provides comprehensive feasibility checks, GDMS material certification data, and factory-direct wholesale pricing within 60 minutes.