Evacuated glass and metal sealing tube application to solar plant
After ten years of technical research and development, thousands of tests, we got technology to melt glass and steel together. We use times of Kovar between glass and steel, and bellowed photos show the finished receiver tubes, with different length of 2 meters and 4 meters, and the diameter can be 4060mm/130mm/70mm, 2000mm/125mm/70 and 2000mm/100mm/40mm.
Product Specifications:
1. Coated Glass-Steel Vaccum Tube used for parabolic trough solar collector
2. Using Kovar make connection
3. 4060mm in length
4. Diameter: 125mm
5. Thickness: 2mm/3mm
6. Temperature can reach: 400~500 Degree centigrade
7. Can produced in large quantity already
The paraboli trough solar receiver tube also called absorber tube, it is the stainless steel pipe treated with a low emitted and high absorptive coating, encased in a high transmittance glass cylinder, the space between the pipe and glass cover is evacuated.
Some test data on the Receiver Tubes:
Density fo axially heat flow ≥ 28MW/m2 |
Total radiation activity α: 1.4*10-1Bq/g |
Effective service life ≥ 150000h |
Heat flux ≥ 14MW/m2 ºC |
Radiation activity - β: 1.7*10-1Bq/g |
Features:
1. Advanced glass-metal hot sealing technology: linear expansion coefficient of borosilicate glass and sealing alloys is similar which can realize glass-metal sealing. It solves the mismatch of linear expansion coefficient between glass and metal.
2. Selective absorbing coating can withstand high temperature from 400 ºC to 500 ºC in a high vacuum condition, to ensure that the sunlight selective absorption coating can keep long-term stability of absorption ratio at high operating temperature.
3. All parts of the vacuum tube pass high temperature and high vacuum exhaust and the tube has a long-acting getter, ensuring it can maintain a high degree of vacuum during its using process.
4. Paten-designed elastic sealing components and sealing protection devices, ensuring stable and reliable sealing.
5. It ends are plug structure made by precision turning, easy to install and weld and ensuring the straightness of the system.
Derived from the thermal control coating technology special for Chinese aerospace satellite
The world's only dual-ceramic coating structure made by use of twin magnetron sputtering technology can work stably for a long time in the vacuum environment than 800ºC or atmospheric environment of less than 450ºC, which has the unique features of high temperature resistance and long life.