COAX® Ultron® system

 

COAX range, Dockweiler – Electropolished double-wall tube for hazardous ultra-pure fluids in microelectronics.

 

The COAX Ultron system is designed for fluids where a leak is not an option and where surface purity determines product quality:

 

Semiconductor specialty gases (HF, HCl, HBr, NH₃, H₂), ultra-pure corrosive wet chemicals, injectable pharmaceutical fluids under containment.

 

Two concentric tubes, an inner process tube in electropolished Ultron quality and an outer safety tube in TCC quality, separated by a controlled annular space.

 

Used in high-purity microelectronics (semiconductor fabs, photovoltaics, batteries), in biopharmaceuticals for toxic or highly potent fluids (HPAPI, cytotoxics) and in fine chemicals R&D under containment.

 

 

Surface finish

 

Component	Treatment	Internal Ra	External Ra
Inner process tube	Ultron, high-purity electropolished	≤ 0.25 µm (10 µin)	—
Outer safety tube	TCC, bright finished

 

Ultron electropolishing removes the work-hardened surface layer and homogenises the passive layer, reducing metal release and particle retention by a factor of 3 to 5 compared with equivalent mechanical polishing.

 

Tubes and fittings prepared for orbital welding. Electropolishing according to Dockweiler procedure Doc. 8.4-40/3.1/3.3.1. Degreased for ultra-pure gas service in accordance with CGA G-4.1-2018 and ASTM G93 Level A.

 

Cleaning and packaging in an ISO Class 4 / Federal Class 10 cleanroom.

 

 

Material

 

316L stainless steel with controlled sulphur content for optimal orbital weldability and minimal surface sulphide inclusions.

 

 

Operating principle

 

Three operating modes for the annular space, selected according to use.

 

• Leak detection using a carrier gas, typically ultra-pure nitrogen or helium at an overpressure of 0.5 to 2 bar, with a downstream differential pressure sensor or process-gas-specific detector. Any pressure loss or appearance of the medium in the annulus triggers the alarm before personnel exposure or cleanroom contamination.

 

 

• Passive secondary containment for SEMI S2-classified toxic gases, where the annulus routes any leak to a secure drain point, with no release to the atmosphere and no cross-contamination.

 

 

 

• Temperature maintenance, where the annulus carries a heat-transfer fluid to prevent condensation or crystallisation of a precursor in the inner tube. Typical case: low vapour pressure CVD/ALD precursors.

 

 

Connection and welding

 

System prepared for orbital welding on the inner tube.

 

 

Dimensional standards

 

Metric and imperial dimensions compliant with ASME BPE, SEMI F19 and DIN 11866 series C.

 

 

Traceability and packaging

 

Each component is supplied with a 3.1 material certificate according to EN 10204, with dual traceability for inner and outer tubes (grade, heat, batch, dimensions, electropolishing report).

 

Laser marking on the OD of the outer tube. Full traceability from raw material to delivery.

 

Components packed in a cleanroom, sealed double polyethylene bags, with capped ends.

 

Oxygen degreasing according to ASTM G93 for oxygen and specialty gas services.