solar water heater

three-target glass solar vacuum tube 1, Three-target Solar vacuum tube for solar water heater2, ISO9001,ISO14001, CE certifications3, 0.91 transmittance of the outer tube 4, 10 to 12 days delivery time 5, five years warranty Specifications: 1, Vacuum tube is consists of two layer of glass tubes2, ISO900:2000, CE certificate;3, 0.91 transmittance of outer tube 4, The outer tube is made of extremely strong transparent quartz sand which can resist impact from hail up to 30mm 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. Structure All-Glass Double Tube Co-Axial Structure Glass Material High Borosilicate 3.3 Glass External Pipe Diameter & Thickness dia.=47±0.5mm &=1.6mm, dia.=58±0.5mm &=1.6mm, dia.=70±0.5mm &=2.0mm, Internal PipeDiameter & Thicknessdi dia.=37±0.5mm &=1.6mm, dia.=47±0.5mm &=1.6mm, dia.=58±0.5mm &=1.6mm, Pipe Length 1500mm, , 1800mm Absorptive Coating PropertyStructure Cu/SS-ALN(H)/SS-ALN(L)/ALN Sediment Method Three Layer Magnetron Sputtering Plating Specific Absorptionas 0.92~0.96(AM1.5) Emission Ratio 0.01~0.03(80°C±5°C) Vacuum P≤2.0×10-3Pa Idle Sunning Property Y= 260 ~ 300m²°C/KW Solar Irradiation for Obtaining a Preset Water Temperature H≤4.7 MJ/m²(dia.58)H=3.7~4.2 MJ/ m² H≤3.7 MJ/ m²(dia.47)H=2.9~3.2 MJ/ m² Average Heat Loss Coefficient Ult=0.4~0.6W/( m².°C) Pressure-Endure Ability 0.6Mpa Hail-Endure Ability 30mm Lifetime more than 15years