Solar-Vakuumröhren

solar evacuated tube ModelsSingle-target vacuum tubeStructureAll glass double tube co-axial structureGlass materialHigh borosilicate 3.3 glassOuter tube diameter and thicknessΦ47±0.7mm/Φ58±0.7mmInner tube diameter and thicknessΦ37±0.7mm/Φ47±0.7mmTubes length1500±4mm/1800±4mmMaterial of coatingAL/N/ALAbsorptance0.90 0.94VacuumP≤2×10-3paTransmittance of Outer Tube0.93Stagnation temperature (height)250 270°cHeat-loss coefficient≤0.6w/ m2*°c)Bearing hailstone abilityhailstone diameterΦ25mmPressure-endure ability1MPaLife span15 years