We use special borosilicate glass tubes / borosilicate glass rods made of borosilicate glass 3.3 of the first water resistance class. These special glass tubes / special glass rods are particularly characterized by high thermal shock resistance and high resistance to water, acids, alkalis and organic substances. Even over long exposure times and at temperatures above 100 °C, the chemical resistance of these glass tubes and glass rods surpasses that of most metals and other materials, making them ideal for a wide range of applications in medical technology, laboratory applications and analytics. Since this glass can also be used permanently at temperatures up to 450 °C, borosilicate glass tubing can be found in many technical applications that cannot be realized with other types of glass (such as soda-lime glass).
Special properties of borosilicate glass tubes / rods
- high thermal shock resistance
- refractory glass tube
- minimal thermal expansion
- corrosion resistant glass
- clear and almost colorless glass tubing
- neutral with aggressive chemicals
- very good resistance to acids, alkalis and organic substances
- low specific glass weight
- high UV transmission & good IR transmission
- good scratch and abrasion resistance
- high elasticity and mechanical strength
- versatile machinable glass tube
- special lengths up to 3000 mm possible
Typical applications
- chemical and waste water plants
- sight glasses and viewing windows – even at high temperatures
- glass tubes for mushroom heaters and infrared radiators
- glass tubes for lamps & luminaires
- measurement, control and sensor technology
- attachment glasses for powerful light sources
- environmental technology
- arts and crafts
- photovoltaic glass tubes
- glass for biotechnology and medical technology
- laboratory glass & glass tubes for glassblowers
Chemical properties
Chemical composition: 81% SiO₂ – 13% B₂O₃ – 4% Na₂O/ K₂O – 2% Al₂O₃
Hydrolytic resistance: Water resistance class HGB 1, Acid class S 1, Alkali class A 2
Physical properties
Density: 2.23 g/cm³
Refractive index: ω=1.473
Compressive strength: according to standard DIN EN 1595
Transformation temperature Tg: 525 °C
Tensile strength: 500 °C
Young’s modulus of elasticity: 64 · 10³ N · mm²
Poisson’s ratio μ: 0.2 (according to DIN 13 316)
Mean coefficient of thermal expansion: 3.25 x 10-6/K (20-300 °C) (according to ISO 7991)
Electrical properties
Dielectric resistance: 4.6 (1 MHz, 25 °C )
Logarithm of volume resistance: 8.0 Ω × cm (250 °C), 6.5 Ω × cm (350 °C)
