Three-target Solar Vacuum Tube for Water Heater

We are offering three-target solar vacuum tube etc. Three-target all-glass vacuum tube has property and spec. As following:
1. All-glass double-tube co-axial structure, high borosilicate 3.3 glass ;
2. Transmission ratio of the outer glass tube;
3. Structure: cu/ss-aln(h)/ss-aln(l)/aln.
4. Sediment method: 3 target magnertron sputtering plating ;
comparing to al-n-al vacuum tube, it has advantages in cold area as following:
a. Absorbance: 12% higher.
b. Emission ration: 30-49% lower.
c. In alpine area, copper ions emission ration is lower than that of aluminum ion. So it could work properly even circumstance temp. Is lower than -30deg c.
d. Stainless steel ion has performance of high temp. Resistant, anti-stagnation temp. Coating will not decay or get aging or disappears.
dia. 47 with length of 1500mm.
dia. 58 with length of 1500mm.
dia. 58 with length of 1600mm.