Product name
Glass tubes for solar water heater
Vacuum tube type
47*1800,58*1800,58*2100...
Coating structure
Cu/SS-ALN(H)/SS*SLN(L)ALN
Specific absorption
93%-96%(AM1.5)
Emission ratio
0.04-0.06(80C+-5C)
Vacuum tightness
<=5.0*10-3Pa
Heat-loss coefficient
0.4-0.6W(m2.c)
Pressure-endure ability
0.6MPa
Thermal expansion
3.3*10-6k