Borosilikatglas Rohr

BOROSILICATE GLASS TUBING AND ROD ( EXPANSION 3.3) Physical Data: No.Physics PerformanceNumerical ValueUnit1Medium coefficient of linear expansion α20/300 acc.To DIN 52328 3.3 0.110-6 K-1 2Transformation Temperature 525 15 3Viscosity temperatures (dPa·s) 1014.7 510 10 1013.2 upper annealing temperature 560 10 107.5 softening point 820 10 104 working temperature 1260 20 4Maximum short-time working temperature 500 520 Density ρ 2.23 0.02g/cm3 6Modulus of elasticity E 64103 N/mm2 7Poissons ratioμ 0.201 8Thermal conductivityλw(20-100) 1.2W/m2K 9Temperature for the specific electrical resistance of 108Ω·cm(DIN52326)tk 100 250 10Electrical volume resistance logarithm(Ω·cm) At 250 8 At 350 6.5 11Dielectric Properties (1MHz,25) Dielectric figureε 4.61 Dielectric loss factor tanδ 3710-4 12Refractive index(λ=587.6nm)nd 1.4731 13Stress-optical constant(DIN52314)K 4.010-6mm2/NChemical Composition in approx.weight % (main components) SiO2 B2O3 Na2O + K2O Al2O3 81 13 4 2 Chemical Data: Hydrolytic ClassISO719 1 Acid ClassDIN12116 1 Alkali ClassISO695 2 PACKING Glass tubes are layered into bundles with a square or rectangular cross-section. They are packed into the geometrically tightest space and then covered at each end with transparent shrink film. Then they are packed into carton. This means that no movement of the tubing is possible during transportation, so that the package is more stable and reliable. The shrinks film at each end of the bundle cover each tube and provide the very best protection against contamination.