Product description
The vacuum tubes consists of two glass tubes which are fused together at one end. The inner tube is coated with a selective surface that absorbs solar energy well but inhibits radiative heat loss. Vacuum tubes adopt borosilicate glass and can resist 25mm hail.
Technical data
|
Model
|
1.5m/47（standard）
|
1.8m/58（standard）
|
|
Length
|
1.5m
|
1.8m
|
|
Outer tube diameter
|
47mm
|
58mm
|
|
Inner tube diameter
|
27mm
|
47mm
|
|
Glass thickness
|
1.5mm
|
1.5mm
|
|
Material
|
Borosilicate Glass 3.3
|
Borosilicate Glass 3.3
|
|
Absorptive Coating
|
AL/N/AL
|
AL/N/AL
|
|
Absorption coefficient
|
>90%
|
>90%
|
|
Emission coefficient
|
<10%
|
<10%
|
|
Stagnation Temperature
|
>200℃
|
>200℃
|
|
