FITOK coaxial tubing and fittings, designed to deliver special fluid such as volatile or toxic gases, are widely used in semiconductor and other industries.

A coaxial tube consists of a process tube and a safety tube, with the process tube on the inside and the safety tube on the outside. In the event of a leak in the process tube, hazardous fluid will enter the outer tube and be evacuated after safe disposal. Same as our EP tubing, process tubes are supplied with the electropolished surface finish as well. FITOK provides a full range of coaxial tubing and fittings, such as 45° elbows, 90° elbows, equal tees, reducing tees, etc.


  • The internal surface of inner tube is electropolished with the roughness up to Ra ≤ 5 µin (0.13 µm)
  • The internal surface of outer tube is bright annealed, or bright annealed after precision cold working
  • Ultrasonically cleaned, washed, rinsed, and purged and dried with hot nitrogen of high purity in ISO 6 cleanroom
  • Assembled in ISO 4 cleanroom, tubing ends are capped and tubing is packed in double polyethylene bags with inner bag filled with 99.999% nitrogen