Product Description

solar evacuated tubes 1.High efficiency than flatplat 2.Pressure system 3.*0year manufacture experience ***** solarkeymark The outer tube is made of extremely strong transparent quartz sand which can resist impact from hail up to *5mm in diameter.5, The inner tube is also made of quartz sand, but it is coated with a special selective coating with strong heat absorption and lowest heat loss.6, The air is evacuated from the space between the two glass tubes to form a vacuum, so it eliminates heat loss.7, This why the tubes are able to absorb the energy from infrared rays which can pass through clouds.8, So it also can operate in low temperature and low sunlight medium. MODELITEMSGB(single target) ConfigurationDouble-layer concentric boronsillicate glass tubes Glass thermal expansion coefficient3.3****6/3.3****6/ Diameter of outer tube*7±1mm*8±1mm Diameter of absorber tube*7±1mm*7±1mm Thickness1.5mm(±0.1mm)1.6mm(±0.1mm) Transmittance of outer tube0.**0.*1 Length***0±5mm***0±5mm Solar selective absorbing coatingAl-N/AlAl-N/Al Absorptance(AM1.5)≥0.*9≥0.*9 Emittance≤0.***0≤0.***0 VacuumP≤5****3PaP≤5****3Pa Stagnation parameter≥**0/KW≥**0/KW Average Heat loss coefficient≤0.*5W/(*)≤0.*5W/(*) Solar irradiation under stagnation≤3.5MJ/≤3.5MJ/ Hailstone resistancehailstone diameter*5mmhailstone diameter*5mm Pressure-endure ability0.6mPa0.6mPa