OEM High-Temperature Quartz Tubes, Plates & Assemblies
Manufactured by Lianyungang Zelvo Quartz Products Co., Ltd. in Donghai County – China's historic crystal and quartz capital. Each component is custom fabricated with laser drilling, high-precision fire polishing, and tight-tolerance redrawing.
Precision Quartz Capillary Tubing: Material Physics & Geometrical Anatomy
A rigorous examination of ultra-narrow bore fused silica and quartz capillaries for R&D scientists, instrumentation OEMs, and semiconductor equipment procurement engineers.
Micro-Bore Geometries & Tight Tolerances
Unlike standard industrial sight glass or heavy furnace tubes, custom OEM capillary tubes feature internal diameters (ID) scaling from sub-5 microns (µm) up to 2.0 mm, with wall thicknesses calibrated to resist pressures exceeding 10,000 psi (68.9 MPa). Modern micro-drawing towers utilize laser-interferometric micrometer feedback loops to maintain outer diameter (OD) and bore concentricity within ±0.002 mm across continuous lengths.
Purity Grades: Natural Quartz vs. Synthetic Fused Silica
Selecting the correct precursor determines optical transmission, background fluorescence, and de-vitrification threshold. High-purity natural fused quartz (99.99% SiO₂) is optimized for high-temperature furnace gas samplers and general chromatography. Synthetic fused silica (produced by vapor axial deposition or chemical vapor oxidation of SiCl₄) delivers ≥99.9999% purity with near-zero transition metal impurities, crucial for CE, flow cytometry, and DNA sequencing.
Thermal & Chemical Boundary Resilience
Pure silica features an extremely low coefficient of thermal expansion (α = 5.5 × 10⁻⁷ /K), giving quartz capillaries immunity to catastrophic thermal shock. Rapid transitions from 1100°C furnace zones down to ambient fluid quench baths do not induce micro-cracking. Furthermore, quartz exhibits universal chemical inertness across the full acidic spectrum (except hydrofluoric acid and concentrated phosphoric acid above 300°C), preventing sample leaching in trace analytical workflows.
Fused Silica & Quartz Capillary Physical, Thermal & Optical Benchmark
The quantitative data below reflects baseline specifications for optical and semiconductor grade fused quartz tubing fabricated at Zelvo Quartz facilities.
| Physical / Engineering Property | Standard Testing Protocol | Natural Fused Quartz Grade | Synthetic Fused Silica (UV Grade) |
|---|---|---|---|
| Silicon Dioxide Content (SiO₂) | ICP-OES / GD-MS | ≥ 99.99% | ≥ 99.9999% (Ultra-Trace Pure) |
| Density (ρ) | ASTM C693 | 2.201 g/cm³ | 2.203 g/cm³ |
| Coefficient of Thermal Expansion (CTE) | Dilatometry (20°C - 320°C) | 5.5 × 10⁻⁷ K⁻¹ | 5.1 × 10⁻⁷ K⁻¹ |
| Continuous Working Temperature | Thermal Equilibrium in Air | 1100°C | 1150°C |
| Peak Strain & Softening Points | ASTM C336 / C338 | Strain: 1070°C | Soft: 1683°C | Strain: 1075°C | Soft: 1710°C |
| Refractive Index (nd at 587.6 nm) | Abbe Refractometry | 1.4585 | 1.4584 |
| Spectral Transmission Window | Spectrophotometric Scan (10mm) | 260 nm – 2500 nm (>90%) | 185 nm – 2500 nm (Deep UV Grade) |
| Hydroxyl Radical Content (OH⁻) | FTIR Absorption @ 2.73 µm | < 5 ppm to 30 ppm | Standard: <1 ppm | High-OH: >1200 ppm |
| Dielectric Breakdown Strength | ASTM D149 (20°C, 1mm thickness) | 25 - 40 kV/mm | 40 - 50 kV/mm |
Precision Capillary Profiles & Complex Cross-Sections
Modern analytical instrumentation requires custom-engineered cross-sectional fluid paths. Zelvo Quartz leverages high-precision graphite and tungsten redraw dies to produce customized internal and external geometries.
Multi-Lumen / Twin Bore Tubes
Designed for coaxial fluidics, dual-sensor thermocouple protection sleeves, and split-channel HPLC sampling. Dual or quad isolated internal bores preserve identical thermal profiles without cross-contamination.
Square & Rectangular Capillaries
Flat outer surfaces eliminate cylindrical optical lens distortion, providing orthogonal excitation and emission pathways for laser-induced fluorescence (LIF), capillary electrophoresis, and micro-flow cytometry.
Tapered & Micro-Nozzle Tips
Thermally pulled, ground, and flame-polished micro-tips with orifice diameters down to 1.0 µm. Engineered for electrospray ionization mass spectrometry (ESI-MS), nanospray emitters, and micro-injection probes.
Thick-Wall High-Pressure Capillaries
Engineered with OD-to-ID ratios reaching 10:1 or greater. Withstand hydrodynamic burst pressures exceeding 1,200 bar, making them indispensable for Ultra-High Performance Liquid Chromatography (UHPLC).
Where Precision Quartz Capillaries Deliver Critical Value
Across high-tech industries, quartz capillary tubing resolves severe engineering constraints related to high temperature, chemical attack, electrical insulation, and high UV transmittance.
Gas Chromatography & Analytical Columns
High-purity quartz capillaries serve as inert transfer lines and analytical column baselines. With ultra-smooth inner surfaces (Ra < 0.5 nm), our tubes eliminate active metal sites that cause peak tailing in GC and CE workflows.
Biomedical Microfluidics & Flow Cytometry
Custom square and rectangular quartz micro-tubes function as high-efficiency optical interrogation flow cells. High transmittance in deep ultraviolet (down to 190 nm) ensures sensitive detection of fluorophore markers in DNA and protein analysis.
Semiconductor Gas Dosing & Precursor Injectors
Atomic Layer Deposition (ALD) and Chemical Vapor Deposition (CVD) equipment require precise precursor micro-dosing tubes that operate at 800°C–1100°C under reactive halogen atmospheres (Cl₂, NF₃, HBr) without particulate flaking.
Fiber Optic Alignment Ferrules & Splices
With CTE perfectly matched to silica communication fibers, quartz capillaries serve as precision alignment sleeves and collimator ferrules. They maintain optical axis alignment over wide operational temperature ranges from -40°C to +85°C.
Extreme Environment Sensors & Pyrometry
Used as protective sheaths for micro-thermocouples, fiber Bragg grating (FBG) optical temperature sensors, and pressure probes within gas turbines, jet engines, and industrial incinerators operating up to 1300°C.
Hermetic High-Voltage Feedthroughs
Exceptional dielectric breakdown strength (>25 kV/mm) and non-hygroscopic qualities make quartz capillaries effective electrical insulators for mass spectrometer ion source feedthroughs and high-vacuum ionization chambers.
Next-Generation Capillary Trends & Sourcing Intelligence
Key technological shifts and supply chain dynamics influencing global procurement managers and research institutions over the coming decade.
1. Sub-2nm Lithography Purity Demand
As semiconductor nodes scale below 2nm, the permissible threshold for trace element outgassing (particularly alkali metals Na, K and transition metals Fe, Cu) in wafer processing capillaries has plummeted to sub-ppb levels, driving OEM adoption of synthetic high-purity fused silica.
2. Hybrid Femtosecond Laser Micro-Machining
Conventional mechanical diamond sawing causes micro-fissuring and edge chipping on capillary ends. Leading suppliers are adopting ultrashort-pulsed femtosecond laser cutting and trepanning, producing chip-free square end-faces with Ra < 0.1 µm without micro-cracks.
3. Polyimide & Fluoropolymer Coatings
To overcome quartz's inherent mechanical brittleness, procurement demand for polyimide-clad and silicone-buffered capillary tubing is rising. Thin polymer jackets (10–25 µm) shield the external silica lattice from atmospheric humidity, boosting tensile strength past 100 kpsi.
4. Direct-Factory OEM Supply Chain Shortening
Western and Asian tier-1 instrument builders are phasing out regional distributors in favor of direct-from-factory partnerships in primary production hubs like Donghai, Jiangsu. This transition cuts component lead times from 14 weeks down to 10–15 business days while lowering costs 30%–45%.
Precision Fabrication Workflow: From Drawing to Dispatch
A rigorous five-stage manufacturing standard guarantees dimensional fidelity, optical surface quality, and vacuum integrity for custom quartz capillary builds.
Drawing & DFM Review
Engineering verification of ID/OD tolerances, aspect ratios, surface roughness, thermal cycles, and gas flow rates within 2 hours of receipt.
Preform Material Grade Selection
Selecting 99.99% high-purity natural silica or synthetic JGS1/JGS2 based on UV transmission needs, temperature profiles, and hydroxyl requirements.
Precision Thermal Redraw
Computerized vertical draw tower processing with continuous non-contact laser micrometry to guarantee sub-micron bore concentricity.
Finishing & Micro-Machining
Laser end-face cleaving, flame polishing, ultrasonic acid washing, and edge beveling to prevent splintering during assembly.
Class 100 Metrology & Crating
Interferometric inspection, bubble/inclusion rating, shock-proof foam isolation, and secure vacuum-sealed packaging for global air transit.
Why Tier-1 Laboratories & OEMs Choose Zelvo Quartz
Combining verified direct manufacturing, the Donghai raw-material supply cluster, and dedicated engineer-led customer support.
Onsite-Verified Manufacturing Facility
Direct manufacturer located in Donghai County, Jiangsu – China's historic crystal capital. Fully audited physical workshops with verified legal entity standing.
Drawing-Based Prototyping (1-Piece MOQ)
From one-off prototype research runs to high-volume production lines. Full compatibility with standard CAD formats (.DWG, .DXF, .STEP, .PDF).
Direct Engineer Quoting (≤2h Response)
Technical inquiries are evaluated directly by senior glass engineers with 10+ years hands-on experience, providing rapid DFM and tolerance feedback.
Certified Purity: ≥99.99% Guaranteed
Full spectroscopic purity verification across every melt. Optical UV & IR grades ensure zero un-melted quartz particles and exceptional clarity.
Proven Customer Loyalty: 37% Reorder Rate
Backed by a 4.9/5 buyer rating and recurring OEM contracts across North America, Europe, Southeast Asia, South America, and the Middle East.
Zero-Breakage Global Crating & DDP Logistics
Multi-layer shock-absorbing foam and reinforced export plywood crates. Supported trade terms: FOB, CIF, EXW, FCA, and full door-to-door DDP.
Frequently Asked Questions: Sourcing Custom Quartz Capillaries
Direct technical answers to common questions regarding tolerances, cutting methods, purity certification, and international shipping.
What are the achievable inner diameter (ID) and outer diameter (OD) tolerances for custom capillary tubes?
Our standard production tolerances for precision-drawn fused quartz capillaries are ±0.005 mm for both ID and OD. For high-precision optical, chromatography, and flow cytometry applications, we utilize advanced continuous laser-micrometer drawing towers capable of holding tolerances down to ±0.002 mm (2 µm), with concentricity exceeding 98%.
How does synthetic fused silica compare to natural quartz in capillary manufacturing?
Natural fused quartz is manufactured by melting high-purity natural silica sand (≥99.99% SiO₂). It provides excellent high-temperature performance (up to 1100°C continuous) and is cost-effective for general lab furnaces, heaters, and standard analytical lines. Synthetic fused silica is synthesized via the chemical vapor oxidation of silicon precursors (e.g., SiCl₄), achieving ultra-high purity (≥99.9999% SiO₂) with near-zero heavy metal impurities (Al, Fe, Ti < 0.1 ppm). Synthetic silica provides superior deep-UV transmittance down to 185 nm and eliminates background fluorescence, making it essential for UV capillary electrophoresis, flow cells, and excimer laser systems.
What methods are used to cut quartz capillary tubes cleanly without micro-cracking or jagged edges?
Standard mechanical cleaving can generate micro-chips and ragged edges that cause fluid turbulence or optical scatter. Zelvo Quartz employs three precision cutting techniques: (1) CO₂ / Picosecond Laser Cutting, creating square, crack-free ends with microscopic heat-affected zones; (2) High-Speed Diamond Blade Dicing with active fluid cooling, followed by mechanical fine-lapping; and (3) Hydrogen-Oxygen Flame Polishing to round and seal cut edges for improved mechanical durability.
Can you produce custom capillary tubes with non-standard cross-sections, like square, rectangular, or multi-bore?
Yes. Custom cross-sections are a core engineering capability. We produce square bore/square outer profile capillaries, rectangular micro-fluidic channels, oval cross-sections, and multi-lumen (twin bore, quad bore, up to 7 isolated parallel lumens). These geometries are commonly used in laser-induced fluorescence (LIF), electrophoretic optical windows, and multichannel sensor probes.
What is the minimum order quantity (MOQ) and typical lead time for custom OEM prototypes?
To support academic research, R&D proof-of-concept trials, and early-stage instrumentation prototyping, our MOQ for custom-dimension capillary parts is 1 piece. Standard prototype orders are fabricated and dispatched within 7–10 working days. For high-volume production orders (1,000 to 100,000+ units), scheduled blanket orders and expedited deliveries are available.
How do you protect fragile, thin-walled quartz capillaries during international shipment?
Capillary tubes are first sealed in dust-free polyolefin casing to prevent atmospheric moisture and particle contamination. They are then supported in custom-cut, high-density polyethylene (EPE) shock-absorbing foam inserts within rigid internal cartons. For export shipping, these cartons are packaged into reinforced, non-fumigation plywood cases engineered to withstand drops and lateral impacts. We maintain an international transit damage rate of less than 0.1%.
Which international payment methods, currencies, and Incoterms are supported?
We work with global clients under multiple Incoterms including FOB (Shanghai/Qingdao), CFR, CIF, EXW, FCA, CIP, and door-to-door DDP (Delivered Duty Paid). We accept wire transfers (T/T), Letters of Credit (L/C), PayPal, Western Union, and major international credit cards. Accepted currencies include USD, EUR, GBP, CAD, AUD, JPY, CHF, HKD, and CNY.
Request an Engineering Drawing Review & Quotation
Send your dimensional requirements, CAD drawings, target tolerances, and annual volume estimates. Our senior quartz processing engineers will review your design and return a formal DFM assessment within 2 hours.