Evacuated Tube Collector

Models: 58×1800 structure: three target outer tube diameter: 58±0.7mm inner tube diameter: 47±0.7mm outer tube thickness: 1.6±0.15mm inner tube thickness: 1.6±0.15mm tubes length: 1800±10mm material of coating: copper, aluminum, stainless steel coating: three targets coating absorptance :≥0.92 emittance: ≤0.06 vacuum: less than 5.2×10-4pa transmittance of outer tube :0.92 stagnation temperature (height): 270~300℃ heat-loss coefficient: less than 0.5 w (m2*℃) bearing hailstone ability: 30mm steel ball from 450mm.