Description
This page covers quartz tube at the large-OD, thick-wall end of the general dimensional range — where wall thickness has to scale up with diameter to hold structural integrity, and where large-diameter forming methods become relevant.
Dimensions
| Parameter | Range |
|---|---|
| OD | 50 – 500 mm |
| Wall thickness | 3 – 20 mm+ depending on OD (thicker for larger diameter) |
| OD-to-ID ratio (large tube reference) | 1.1 – 7 |
| Wall thickness error | ≤2% cited for large primary-treated tube |
| Inner surface roughness | ≤20 µm cited for large tube |
Large-Format Production
- Standard drawn quartz tube: straight-drawn from melt, common up to ~300 mm OD.
- Formed (secondary-processed) tube: for OD 500–1000 mm, a graphite-trowel centrifugal reforming process controls diameter and wall thickness on a lathe-type setup after initial draw. This is a specialized capability and should be confirmed with the specific supplier.
- Large-diameter tube working capability up to 500 mm OD is cited among furnace-tube fabricators serving OEM systems such as SVG/Thermco/Kokusai-type equipment.
Thick-Wall Application
- Position / boiler meter tubes — thick wall for mechanical robustness under pressure.
- Furnace and vacuum process tubes where increased wall thickness adds thermal mass and structural stability.
- Wall thickness selected against OD, scaled for large-format structural and thermal requirements.
Trade-offs at Large Scale
Thicker, larger-diameter straight-drawn tube is more prone to defects such as bubbles, gas lines and gas points than smaller tube. Roundness and OD tolerance also tend to be looser at large scale due to gravity effects during high-temperature drawing. Formed or reprocessed tube can address these issues, but it is a secondary and more specialized process.
FAQ
Is OD 500 mm+ tube a standard product or a special order?
It is generally a specialized secondary-forming capability rather than standard drawn-tube stock. Confirm the exact OD, wall and forming route with the specific fabricator.
How does wall thickness scale with OD?
The cited large-format reference uses an OD-to-ID ratio of 1.1–7, with wall thickness increasing as OD increases. Final wall thickness should be confirmed against the structural and thermal load for the intended application.