solar collector tube, 3 layers coating: black 1. we have 3 glass furnaces 2. professioanl manufacturer of vacuum tube

solar collecot tube,

tri-target magnatron sputtered,

inner tube coating surface color: black

specifications:

	Tri-targets vacuum magnetron sputtering
Tube structure	dual tubes, coaxial
Tube material	Borosilicate glass 3.3
Outer tube Dia. and thickness	47mm
Inner tube Dia. and thickness	37mm
Tube length	1800mm
Tube weight
Selective absorbing coating	CU/SS-ALN/ALN
Sediment method	Magnetron sputtering
Vacuum degree	5*10-3
Outer tube transmittance	≥91%
Absorption rate	≥96%
Emittance rate	≤6%
heat loss efficient	≤0.6w/M2°C
Stagnation tempreture	260~300°C
thermal expansion coefficient	3.3*10-6
Pressure endurance	1mpa
Impact endurance( dia.)	≤25mm hailstone
Service life	15year

solar collector tube, tri-target, 58/1800mm, black