Quartz Flanges & Fittings

Quartz Flanges & Fittings

Quartz flanges connect quartz tubes, vessels, and injectors to each other and to metal components in furnace and gas-handling systems. The flange interface must be dimensionally compatible with the mating metal flange, and the quartz body must accommodate the thermal expansion differential between quartz (CTE 0.55×10⁻⁶/°C) and metal (CTE 10–17×10⁻⁶/°C).

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Flange Types

Flat-Face Welded Flange

A solid quartz disc with a precision-ground flat face and bore, fusion-welded to the tube end.

Specification	Value
Face flatness	< 0.05 mm
Bore tolerance	±0.05 mm
Perpendicularity	< 0.1 mm TIR
OD range	50–400 mm
Available face finishes	Ground, lapped, polished

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Stepped / Rabbet Flange

Flange with a machined shoulder (rabbet) that locates concentrically with the mating metal flange bore — provides self-centering for alignment-sensitive assemblies.

Specification	Value
Rabbet diameter tolerance	±0.05 mm
Step height tolerance	±0.1 mm
Concentricity (rabbet to bore)	< 0.05 mm TIR

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Fittings & Adapters

Part Type	Description
Reducing coupler	Joins two tubes of different OD in-line
90° elbow	Quartz tube bent to 90° ± 1°
T-piece	Branch junction, all three ports welded
Tube-to-flange adapter	Converts tube OD to flange face interface
End cap	Closed flat or domed end
Ground joint (24/29, 34/35)	Standard laboratory glass taper joints

All fittings are fusion-welded and annealed, with He leak test (< 1×10⁻⁹ mbar·L/s) on all weld joints.

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Interface Compatibility

Mating Flange System	Quartz Equivalent Available
ASA (ANSI) pipe flange	✓
ISO-KF (NW) quick-flange	✓ (quartz body + metal ring)
Custom OEM bolt pattern	✓ (drawing-based)
Swagelok tube fitting	✓ (quartz stub + SS nut)