Vacuum collector tube and process for preparing coating thereof

Abstract

The invention discloses a vacuum collector tube process, in particular to a vacuum collector tube and a process for preparing a coating thereof. The scheme of the preparation process includes sequentially plating an AlN-Al bonding layer, a pure copper high infrared reflection layer, an Aln-Ti high metal absorbing layer, an Aln-Ti low metal absorbing layer and an AlN antireflection layer on the outer surface of a glass inner tube. According to the vacuum collector tube and the preparation process for the coating thereof, titanium metal is used by the absorbing layer as the main coating material, defects of low stability, fast aging and short service life of vacuum tubes are overcome, the absorption ratio of vacuum collector tube is enabled to be over 96% due to the special coating structure, and the vacuum collector tube is capable of stably supplying industrial hot water for users.

Description

technical field [0001] The invention relates to the processing field of solar vacuum heat collecting tubes, in particular to a vacuum heat collecting tube and a coating preparation process thereof. Background technique [0002] At present, domestic hot water is generally divided into three grades according to water temperature: 40°C-80°C is called domestic hot water, 80°C-250°C is called industrial hot water; 250°C-800°C is called solar thermal water. Hot water for power generation. At present, vacuum tube solar energy can only provide domestic hot water at 40°C-80°C, but cannot provide higher temperature industrial hot water and hot water for solar thermal power generation. The main reason is that it is affected by the core component of solar energy-vacuum The heat collector is limited. Selective absorbing coating is the core of vacuum heat collecting tube. At present, the absorbing coating of solar vacuum heat collecting tube can be divided into three types according to ...

AI Technical Summary

Problems solved by technology

At present, vacuum tube solar energy can only provide domestic hot water at 40°C-80°C, but cannot provide higher temperature industrial hot water and hot water for solar thermal power generation. The main reason is that it is affected by the core component of solar energy-vacuum Collector limited by

Selective absorbing coating is the core of vacuum heat collecting tube. At present, the absorbing coating of solar vacuum heat collecting tube can be divided into three types according to the different preparation materials: 1. AlN-Al coating. This coating technology mainly uses aluminum, aluminum The melting point of the vacuum heat collector is 660.37°C. The vacuum heat collector works at high temperature for a long time, and the AlN-Al coating is easy to age at this temperature, which shortens the service life of the vacuum heat collector; Aluminum, stainless steel, and copper are used as materials. This coating technology is an improvement on the AlN-Al coating technology. The stainless steel in the material makes up for the shortcomings of aluminum that is not resistant to high temperatures, but the coating process takes a long time and has low efficiency. Poor performance; 3. SS-C-Cu coating. This technology mainly uses stainless steel and copper. The disadvantage of this coating technology is that the coating stability is poor, the coating is easily oxidized in the air, the emissivity is high, and the thermal insulation performance is poor.

Therefore, the coating process disclosed in the current technology cannot meet the technical requirements for providing hot water for industrial use and hot water for solar thermal power generation.

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