High-Purity Quartz Vessels & Precision Components
From standard single-neck boiling flasks to multi-port vacuum distillation reaction systems, our integrated cold-cutting and flame-blowing workshops produce laboratory-grade fused silica components with micrometer-level dimensional tolerances.
Optical Quartz Light Guide Cylinder Rod GT Model
High-Temperature Optical Grade Clear Transparent Quartz Glass
Open Ended Fused Quartz Frosted Cylinder & Reaction Vessel Ingot
Transparent Fused Quartz Boiling & Inspection Observation Sheet
Fused Quartz Circular Lab Holder & High-Temperature Crucible Base
Custom 99.99% Pure Quartz Sealing Flange & Boiling Neck Rings
Laboratory Fused Quartz Multi-Port Distillation Transfer Tube
High-Temperature Frosted Quartz Boiling Bath Heating Base Disc
Quartz Boiling Flask Geometries & Engineering Configurations
Selecting the correct quartz vessel configuration requires balancing hydrodynamics, mechanical hoop stress under vacuum, and radiative heat transfer across the vessel walls. Zelvo Quartz fabricates six distinct commercial and research boiling flask lines.
Round-Bottom Quartz Boiling Flasks
Fabricated for spherical thermal distribution under direct burner or mantle heating. The spherical bottom eliminates stress concentration corners, making it the premier choice for boiling organic solvents, high-temperature reflux, and rotary evaporator distillation from 50 mL up to 20,000 mL capacities.
Flat-Bottom (Florence) Quartz Flasks
Engineered with a stress-annealed planar base designed to sit freely on standard hot plates without ring stands. The base thickness is controlled to ±0.2 mm to prevent localized thermal hot spots, facilitating rapid, stable boiling for wet chemical digestion and analytical stock preparation.
Multi-Neck Reaction & Distillation Flasks
Configured with 2, 3, or 4 ground joints (available in parallel or angled formats). Facilitates simultaneous thermometer immersion, inert gas purging (Schlenk line), reagent feeding, and vapor takeoff for fractional distillation setups under full vacuum down to 10⁻⁴ mbar.
Heavy-Wall Vacuum & Schlenk Boiling Vessels
Featuring reinforced cylindrical or round wall thicknesses from 3.5 mm to 6.0 mm. Each unit undergoes polariscopic residual strain evaluation to withstand severe negative pressure and mechanical agitation during cryogenic-to-high-temperature sublimation cycles.
Kjeldahl & Ultra-Trace Acid Digestion Flasks
Specialized pear-shaped and long-neck quartz boiling flasks tailored for concentrated sulfuric, nitric, and perchloric acid boiling. Because high-purity fused silica does not leach boron or alkali ions, it is mandatory for ICP-MS and AAS sample preparation in sub-ppb cleanrooms.
Custom Ground Joint & Flanged Quartz Flasks
Manufactured with precision-ground Standard Taper (ST 14/20, 24/40, 29/42), Spherical Socket/Ball (28/15, 35/20), or O-ring flanged seals. Diamond-ground interfaces are flame-polished along stress boundaries to guarantee leak-tight mating without seizing at high temperatures.
Comprehensive Material Comparison: Fused Quartz vs. Borosilicate 3.3
Why Tier-1 research facilities and semiconductor fabs mandate fused quartz over standard laboratory borosilicate glass.
| Physical / Chemical Metric | Borosilicate Glass 3.3 | High-Purity Fused Quartz (Donghai) | Synthetic Fused Silica | Procurement Impact |
|---|---|---|---|---|
| SiO₂ Content | ≈ 81.0% | ≥ 99.99% | ≥ 99.9999% | Prevents ionic leaching in trace analysis |
| Continuous Working Temp | 450 °C – 500 °C | 1100 °C | 1200 °C | Permits direct flame and high-temp boiling |
| Short-Term Max Temperature | ≈ 520 °C | 1300 °C | 1400 °C | Resists runaway reaction excursions |
| Softening Point | 820 °C | 1683 °C | 1730 °C | Zero structural deformation during boiling |
| Thermal Expansion (CTE, 20-300°C) | 33 × 10⁻⁷ /K | 5.5 × 10⁻⁷ /K | 5.2 × 10⁻⁷ /K | Quenchable into ice water from 1000°C without crack |
| UV-Vis Spectral Transmittance | Poor below 310 nm | High (220 nm – 2500 nm) | Extreme (185 nm – 2600 nm) | Enables photochemical UV-irradiated boiling |
| Acid Resistance (except HF / H₃PO₄) | Moderate (Alkali attack) | Exceptional / Zero Leaching | Exceptional | Impervious to boiling aqua regia and HNO₃ |
| Cost Ratio (Procurement Benchmark) | 1.0x (Baseline) | 3.5x – 5.0x (Optimal TCO) | 12.0x – 20.0x | High durability yields 6x operational lifespan |
Future Procurement & Manufacturing Trends for Quartz Glassware (2025–2030)
Global supply chains for scientific quartz glassware are undergoing rapid structural shifts driven by semiconductor reshoring, green hydrogen heating, and automated glass fabrication.
Low-Hydroxyl (<5 ppm OH) Synthesis
Modern vacuum boiling of aggressive halogenated precursors demands quartz with minimal OH content. Low-OH vessels eliminate water vapor desorption at extreme temperatures, preventing bubble inclusion and infrared radiation absorption during critical crystal synthesis.
Automated CNC Robotic Lathe Blowing
While manual mouth-blowing by master technicians remains vital for one-off bespoke apparatus, Chinese factories are integrating multi-axis CNC glass lathes. This enables uniform spherical wall distribution (±0.1 mm) on high-volume 500 mL and 1000 mL flasks, eliminating thin-bottom failure risks.
Class 1,000 Cleanroom Packaging
Global procurement contracts increasingly mandate particulate-free delivery. Chinese manufacturers now integrate ultrasonic DI-water rinsing, cleanroom air drying, and ESD-safe vacuum sealing directly at the factory gate, eliminating the need for costly pre-cleaning by the end-user.
Direct-to-Factory Procurement Compression
Western distributor markups on scientific quartz range from 150% to 300%. Sourcing heads in pharmaceuticals and electronics are establishing direct supply agreements with verified Donghai manufacturers like Zelvo Quartz, compressing lead times from 14 weeks down to 10 days for custom drafts.
From CAD Blueprint to Annealed Quartz Vessel
Our closed-loop fabrication process guarantees optical purity, precise joint taper mating, and complete thermal stress release.
Drawing Engineering
Review 2D/3D CAD models (STEP/DWG/PDF), calculate hydrodynamic volume expansion, and verify taper neck clearances.
Raw Tube Profiling
Select certified 99.99% fused silica mother tubes from Donghai deposits, cut to length using precision diamond saws.
Flame Lathe Forming
Hydrogen-oxygen flame heating at 1800°C–2000°C. Skilled glass blowers expand the bulb, achieving true spherical symmetry.
Precision Joint Welding
Micro-welding of ground taper joints (ST 24/40, etc.) and sidearms with zero weld spatter and flawless angular alignment.
1150°C Kiln Annealing
Programmed thermal de-stressing in electric kilns followed by polariscope strain verification and triple-bubble inspection.
Lianyungang Zelvo Quartz Products Co., Ltd. – Donghai Crystal Capital
Located in Donghai County (Lianyungang, Jiangsu), the undisputed global capital of natural silica quartz reserves, Zelvo Quartz bridges Chinese raw material cost leadership with European-grade precision glass engineering.
Raw Material Direct Advantage
Direct mine-to-furnace integration guarantees 99.99% SiO₂ fused silica with total metallic impurities below 20 ppm. Zero middleman markup on raw material feeds.
1-Piece Rapid Prototype MOQ
We welcome 1-piece sample orders for university laboratories and pilot research setups, scaling seamlessly to 5,000+ piece production runs for global labware distributors.
≤ 2-Hour Technical Response
Our sales engineering desk operates on real-time quotation windows. Receive drawing feasibility feedback, CAD modifications, and DDP shipping quotes within 120 minutes.
Shock-Proof Global Transit
Custom-cut polyethylene foam cradles, dual-wall corrugated inner cartons, and reinforced fumigated plywood export crates ensure zero breakage across air and ocean routes.
Frequently Asked Questions: Sourcing Quartz Boiling Flasks
Real-world engineering, tolerance, and commercial answers for laboratory supply managers and technical buyers.
Yes. Unlike borosilicate glass which softens near 520°C and requires ceramic wire gauze to diffuse heat, fused quartz has a softening point of 1683°C and an extremely low thermal expansion coefficient (5.5 × 10⁻⁷ /K). It can withstand concentrated, direct oxy-gas burner flames without cracking or warping.
Devitrification is the phase transformation of amorphous fused silica into crystalline cristobalite, typically occurring above 1050°C in the presence of surface alkaline contaminants (fingerprints, dust, alkali salts). To prevent hazing and micro-cracking, always degrease vessels with pure ethanol or a 5% HF rinse before heating above 1000°C.
Yes, mechanically they fit Standard Taper joints (e.g., ST 24/40). However, caution is required under elevated temperatures: because quartz and borosilicate possess vastly different thermal expansion coefficients (5.5 vs. 33 × 10⁻⁷ /K), thermal cycling will cause the borosilicate joint to seize or fracture. We recommend all-quartz distillation assemblies for high-temperature work.
Our standard hot-flame fabrication maintains outer diameter (OD) and spherical bulb tolerances of ±0.5 mm to ±1.0 mm depending on capacity. Ground taper joints adhere to ISO 383 standards (1:10 taper ratio). For critical flange faces and laser-cut apertures, we achieve precision tolerances down to ±0.05 mm.
We maintain an agile 1-piece MOQ for prototyping, custom research drafts, and pilot evaluations. Standard catalog capacities (100 mL to 2000 mL) ship within 3 to 5 business days. Bespoke CAD drawings requiring custom multi-neck configurations or heavy-wall forming typically take 7 to 10 working days.
Our transit breakage rate is under 0.2%. Every quartz flask is individually enveloped in precision-profiled high-density polyethylene foam, packed inside puncture-resistant inner cartons, and palletized inside multi-layer plywood export crates. All shipments carry comprehensive transit insurance with immediate free replacement upon photographic verification.
Hydrofluoric acid (HF) rapidly dissolves quartz at all temperatures. Hot, concentrated phosphoric acid (H₃PO₄) attacks quartz above 150°C, and strong alkaline solutions (such as concentrated NaOH or KOH) etch the silica network at boiling temperatures. Aside from these specific media, quartz is chemically inert to all strong acids, halogens, and organics.
We support FOB Shanghai/Qingdao, CIF, CFR, EXW, FCA, CPT, and full Door-to-Door DDP (Delivered Duty Paid) shipping to North America, the EU, Southeast Asia, and the Middle East. Accepted payment methods include wire T/T, irrevocable L/C at sight, PayPal, and credit cards in USD, EUR, GBP, AUD, and CNY.