Product Description

Evacuated tube are the absorber of the solar water heater , This type of tube is chosen for it’s reliability , performance and low manufacturing cost Each evacuated tube consists of two glass tubes made from extremely strong borosilicate glass, The outer tube is transparent allowing light rays to pass through with minimal reflection, The inner tube is coated with a special selective coating (AL-N/AL)which features excellent solar radiation absorption and minimal reflection properties The top of the two tubes are fused together and the air contained in the space between the two layers of glass is pumped out while exposig the tube to high temperature , This “evacuation” of the gasses forms a vacuum which is an important factor in the performance of the evacuated tubes ⅠHigh heat-collecting effciency: The vacuum magnetic-controlled sputtered aluminum-nitrogen-aluminum selective absorption coating has a solar absorptance≥0.*3, a heat emittance≤6%, a low heat loss , and a good thermal-retention effect Ⅱ Good weather-resistanc:It has a good all-year thermal efficiency and is able to withstand the front impact by the hail of a dianmeter below *5mm and pressure 0.6Mpa Ⅲ Long service life:ensures a service life of *5 years for the evacuated tube ☆ Properties of all-glass evacuated solar collector tubes Item Measured Value Specification in Chinese state standard Ptance of the solar selective absorbing coatings α≥0.**1 α≥0.*6(AM1.5) Hemisphere emittance ε≤0.*6 ε≤0.*9(*0±5℃) Solar radiance exposure using sun as medium H≤2.**9MJ/m² H≤3.8MJ/m² Ation parameter using air as medium Y≥**0 m²℃/Kw Y≥**5 m²℃/Kw Average heat loss coefficient ULT≤0.*8W/m2℃ ULT≤0.9W/m2℃ Model Outer diameter/inner Diameter(mm) Length(mm) Package 1 *8/*7 ***0/***0/***0 Carton 2 *7/*7 ***0/***0/***0 Carton