powerful solar vacuum tube

Solar vacuum tube

Features
Product Name: Three-high vacuum tube
Place of Origin: China
Structure: All glass concentric dual tube structure
Glass material: Borosilicate glass
Outer tube diameter and thickness: 58+/-0.7mm/1.6mm
Inner tube diameter and thickness: 47+/-0.7mm/1.6mm
Length of tube: 1800(+/-5mm)
Construction: Graded AL-N/AL selective absorption coating
Heat-absorbing rate: more than 92%
Emission of heat: less than 8% (80degree)
Vacuum degree: less than 0.005Pa
Solar radiance exposure: less than 2.8MJ/M2
Calories absorption: 9.1MJ/M2
Average heat loss: less than 8.6W/(M3.K)
Pressure-endure ability: 0.2Mpa
Bearing hailstone ability: 25mm in diameter
Lifespan: 15years.
High solar-thermal conversion and low heat loss
Stable advanced coating up to 380 degree
Long time warranty to 10 years
High level vacuum ensure operation under cold weather
Vacuum Tube technology:
Models 47mm 1500mm 58mm 1800mm
Weight 1.35kg 2.29kg
Structure All-glass-coaxial All-glass-coaxial
Double-layer tubes double-layer tubes
Outer tube diameter 47mm 58mm
Inner tube diameter 37mm 47mm
Outer Tube thickness 1.6mm 1.8mm
Inner tube thickness 1.6mm 1.8mm
Material of coating Al N/Al N-SS/Cu Al N/Al N-SS/Cu
Absorptance 0.94~0.96 0.94~0.96
Emittance 0.04~0.06 0.04~0.06
Vacuum P≤5*10-3pa P≤5*10-3pa
Stagnation temperature 270~300 270~300
(height)
Heat-loss coefficient ≤0.6w/ m2) ≤0.6w/ m2)
Bearing hailstone ability 25mm 25mm
Pressure-endure ability 1MPa 1MPa