Full-glass solar vacuum heat-collecting tube and preparation method thereof

Abstract

The invention discloses a full-glass solar vacuum heat-collecting tube and a preparation method of the full-glass solar vacuum heat-collecting tube. The heat-collecting tube comprises a vestlet, an inner tube and a support component, wherein an antioxidant selective absorbing coating is arranged on the outer surface of the inner tube, and the coating is sequentially composed of a diffusional bonding layer, an infrared reflection layer, a diffusional impervious layer, an absorbed layer, a suede texture layer and a decreased layer from a base material to the outside in an overlapped mode. By the adoption of the antioxidant solar spectrum selective absorbing coating, even the vacuum degree in a vacuum layer of the vacuum heat-collecting tube reduces or completely disappears, a solar spectrum absorbing film layer has high inoxidizability, the film layer can still work normally, the service life of the heat-collecting tube is greatly prolonged, the evacuation time when the heat-collecting tube is manufactured is short, gas is removed by high temperature, and meanwhile a non-evapotranspired-type getter is activated, the production efficiency is high, the production cost is reduced, and actual heat-collecting area is increased.

Description

technical field [0001] The invention relates to a solar vacuum heat collecting tube, especially a solar vacuum heat collecting tube with an all-glass solar energy vacuum heat collecting tube; the invention also relates to a preparation method of the aforementioned all-glass solar vacuum heat collecting tube. Background technique [0002] At present, China's photothermal heat production is developing very fast, especially its core solar energy vacuum heat collector production technology is very mature, it has reached an annual production scale of over 100 million tubes, and the annual new heat collection area has reached more than 10 million square meters. The stock of vacuum heat collecting tubes has reached nearly 300 million square meters. These heat-collecting elements all use all-glass solar vacuum heat-collecting tubes. The typical film layer is the Al-ALN single-target coating mentioned in Professor Yin Zhiqiang's patent CN85100142 "Sputtering Solar Energy Selective Ab...

AI Technical Summary

Problems solved by technology

[0004] However, the main disadvantage of the above film and vacuum heat collector is that the selective solar spectrum absorbing film used in it has no oxidation resistance and can only be used under vacuum conditions.

[0009] It can also be seen from the processing process that the production process of the entire solar collector tube is complex and requires close connection, and the evaporation of the getter increases the process time and processing cost.

Moreover, the evaporative getter will have a certain amount of outgassing during the evapotranspiration process, and this outgassing after the baking and exhaust sealing is completed will also lead to a decrease in the vacuum degree of the vacuum heat collecting tube

[0010] In addition, the vacuum degassing temperature of the stainless steel tube card used in the vacuum heat collecting tube is relatively high, and most of the residual gas on the tube card is not removed during the baking and exhaust process at about 400 ° C. Therefore, during use, the tube card The released gas will also lead to the reduction of the vacuum degree of the vacuum collector tube

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