Solar Vacuum Glass Tubes – The heart of solar water heating products.
As the most important part for the solar water heaters, the quality and lifetime decide the quality and lifetime of the whole system.
It is a kind of two double layers glass tube, vacuum between the two layers, a kind of absorptive layer coated outside of the inner tube. Made of borosilicate 3.3 glass, which has high light transmission rate, head enough to resist the outside damage(less than 20mm hailstone), good quality to keep the vacuum ,etc.
Based on different coating layers, there are two kinds of glass tubes in the markets, normal tubes and high efficiency vacuum glass tubes, with different diameter ( inner/outer) and length.