Feature
Secondary drawing applies closed‑loop control covering furnace softening, traction stretching, online monitoring and annealing. It delivers tight dimensional tolerance with inner diameter controlled within ±0.005 mm and outer diameter below 0.01 mm. High borosilicate glass is the primary raw material favoured for excellent thermal stability and low thermal expansion coefficient. Processed tubes can reach a minimum wall thickness down to 0.01 mm. The finished parts possess decent mechanical strength yet remain brittle and need careful manipulation. Multiple custom options are available for outer diameter, length and port configurations.
Application
l Scientific Research: X-ray sample carrying, capillary electrophoresis
l Medical: Micro-reagent delivery, microfluidic chips
l Electronics: Fiber optics, sensor packaging
Available Size
Currently, glass tubes (especially high borosilicate glass) can achieve a minimum wall thickness of 0.01mm (10μm) after secondary drawing.
Thin-walled glass capillary: with a minimum
outer diameter of 0.1 mm, a wall thickness of 0.01 mm, and a length of
approximately 80 mm, it has been used in precision applications such as X-ray
diffraction experiments.
These capillaries are mostly made of high borosilicate glass (SiO₂ >78%, B₂O₃ >10%), with a softening temperature of about 815℃. Although they have high mechanical strength, they are brittle and require careful handling.
Customization capabilities: Supports different outer diameters (0.1–10mm), lengths, and port types (such as funnel-shaped openings, closed ends, etc.).