Introduction
    As the key component for solar collectors, our all
    glass evacuated tube is similar to a conventional Dewar flask. This
    product is composed of two borosilicate glass tubes with high chemical
    and thermal shock resistance. The outer side of the inner tube is
    coated with a sputtered solar selective layer. Closed at one end, the
    inner tube for the solar heat pipe is sealed to the outer tube at the
    other end. The annular space between the outer tube and the inner tube
    is then evacuated to eliminate heat loss caused by conduction and
    convection.
    Leading Technology of All Glass Evacuated Tube
    The all glass evacuated SS-ALN cermet solar collector tube is
    produced with interference type solar absorption layer, and the
    technology of metallic membrane plating like SS and Al duplex metallic
    target sputtering manufactured cermet absorption layer, etc. In
    addition, the vacuum tube also employs new interference type selective
    absorption layer with the absorptance α=0.94 and emission ratio ε≤0.06.
The absorption layer for the all glass evacuated tube utilizes SS-ALN (special stainless steel aluminum nitride) absorption layer with good resistance to high temperature. Even if the glass gets melted, the SS-ALN absorption layer will not shed. Our product is characterized by outstanding ageing resistance, long lifespan, low emission ratio and small thermal loss. The excellent heat absorption performance makes it possible for water heating when it is 30°C below.
    Why Us
    1. Our company has automatic all glass evacuated tube
    production line, as well as the advanced and strict testing process,
    which helps us achieve optimal product stability.
    2. With the vacuum degree up to 10-4Pa, the heat loss rate is controlled within 0.03-0.06.
    3. Utilizing metallic copper as the bottom metal layer which is
    characterized by high absorptance, the solar evacuated tube has low
    heat loss, which is just 50% that of the regular vacuum tube. The
    average heat loss of our all glass evacuated tube is ULT≤0.5W/(m2.°C). 
    4. With good insulation performance, the stagnation temperature is higher than 270°C.
    5. The patented technology helps us successfully encounter the
    problem caused by graded coating limitation, realizing the working
    temperature from -40°C to 40°C.
    6. Equipped with 5 full automatic production lines, our company
    is capable of completing the production of 100,000 pieces of high
    temperature resistant evacuated tube, daily.
Full Automatic Production Line for All Glass Evacuated Tube


                 

                

              
    New Product - All Glass Evacuated Tube with Inner Reflecting Layer
    This new series of all glass evacuated tube is coated
    with reflecting layer inside the outer tube to reflect the sunlight to
    the inner tube for solar energy collection and heating, which
    effectively improves the heating efficiency. The solar energy is then
    converted into heat energy to complete liquid heating.
     QA and Test Center for All Glass Evacuated Tube
    As a professional supplier, we lay great emphasis on the product quality
    and customer satisfaction degree. The national largest quality
    assurance system and test centre, which are constructed based on the
    standard stricter than the China National Standard, help us achieve
    outstanding product quality. Apart from ISO 9000 quality assurance
    system certification and CNAS certification, our company enjoys sound
    reputation and solid brand recognition in the global market.




>Specifications of All Glass Evacuated Tube
| Description | Ultra Low Emission Evacuated Tube | All Glass Evacuated Tube with Inner Reflecting Layer | |||||||
| Length (m) | 1.6 | 1.8 | 1.6 | 1.8 | 1.92 | 2.1 | 2 | 2.1 | |
| Structure | Three targets | ||||||||
| Material of glass | Borosilicate Glass 3.3 | ||||||||
| Optional coating type | ALN/AIN-SS/Cu (aluminum nitride, AIN-SS, copper) | ||||||||
| Outer tube diameter (mm) | Φ47 | Φ58 | Φ84 | ||||||
| Outer tube thickness (mm) | 1.6 | 1.8 | 2.0 | ||||||
| Inner tube diameter (mm) | Φ37 | Φ47 | Φ37 | ||||||
| Inner tube thickness (mm) | 1.6 | 1.6 | 1.6 | ||||||
| Absorptance | ≥0.94 | ||||||||
| Emission ratio | ≤0.06 | ||||||||
| Solar transmission rate | ≥92% | ||||||||
| Vacuum degree (Pa) | ≤5.2×10-4 | ||||||||
| Max. temperature(°C) | 300 | ||||||||
| Average heat loss (W/m2.°C) | ≤0.60 | ≤0.60 | ≤0.50 | ≤0.65 | |||||
| Rated Pressure (MPa) | 1.0 | 0.6 | |||||||
| Stagnation parameter (m2·°C/kW) | 241 | 256 | 265 | 284 | 289 | 290 | 314 | 309 | |
| Coefficient of thermal expansion (K-1) | 3.3×10-6 | ||||||||
| Solar radiance exposure (MJ/m2) | ≤3.6 | ≤4.6 | ≤3.0 | ||||||
| Lifetime(years) | 15 | ||||||||
| Quantity | 20’GP | 3240 | 2916 | 2496 | 2304 | 2112 | 1920 | 728 | 728 | 
| 40’GP | 6804 | 5832 | 5376 | 4608 | 4440 | 3960 | 1512 | 1512 | |