Sell Glass vacuum tube

Specification:
Outer Diameter and Inner Diameter (MM) 47 / 37 58 / 47
Length of Tube (MM) 1500, 1600, 1800, 2100
Thickness of Tube (MM) 1. 60 more or less 0. 15
Selective absorbing surface: 3layers, aluminum-nitrogen-carbon (Al-N-C)
Material: Borosilicate glass 3. 3
Color: Blue
Thermal Expansion: 3. 3 multiply 10-6 / k
Maximum Strength: 0. 6 Mpa
Absorption of Selective Coating: above 95 percent
Emission of Selective Coating: below 5 percent
Stagnation Temperature: above200m2 degree / KW
Solar Irradiation for Water Temperature Rise below 3. 0mj / m2
Coefficient of Average Heat Loss below 0. 70w /  (m2 degree)
Vacuum above 3. 0 multipy 10-2Pa (anti heat loose)

The solar tube is made from borosilicate glass 3. 3 and the structure of solar vacuum tubes is as same as the gallbladder of the pot, which is sealed with double glass and the double glass tube is pumped into a high-vacuum. The surface of inner glass is sprayed with selective coating through a special technology. The solar energy absorption rate can reach 94. 5% by the usage of the selective coating, while the rate of thermal radiation below 5. 5percent. Vacuum tube absorbs solar energy, and then heats the water or liquid by heat conduction. The heat loss of liquid is very low through the high-vacuum between inner glass tube and outside, Its stagnation temperature is above 200 degrees. It is widely used in solar water heater, solar collecotor, solar projects.

The sloar energy absorption rate can reach 94.5% by the selective coating, while the rate of thermal radiation below 5.5%.