Speaking of greenhouse construction, we have to talk about several covering materials for greenhouses, the most important of which are three kinds of covering materials. It is mainly divided into three categories: plastic film, glass and PC sunshine board. With the continuous development of domestic greenhouse construction, greenhouses of different regions and uses have different requirements for covering materials. Manufacturers continue to improve the functions and types of covering materials, and they are becoming more and more refined. In addition, with the continuous development of modern facility agricultural greenhouses, the types of greenhouses are subdivided into scientific research greenhouses, productive greenhouses and commercial greenhouses. The expansion of these functions also puts forward higher requirements and challenges for covering material manufacturers.
The first is the commonly used covering material film, whether it is a single arch shed, energy-saving solar greenhouse and multi-span film greenhouse, the film is used as the covering material. Because of the low cost of the film, easy installation and use, simple maintenance, high cost performance, and wide penetration rate, it has become the first choice for greenhouse covering materials. Greenhouse films have been used in China for many years, but the application of high-end films is not very common. The so-called high-end film is a product that has a variety of thicknesses, a variety of additional functions, and can maintain the best efficacy for different crops, different regions, and different environments and climates.
At present, there are many domestic companies engaged in the production and sales of greenhouse film, and specialized and large-scale production plants are mainly concentrated in Beijing, Shanghai and Shandong. The high-end imported membranes on the market mainly come from Japan, Israel, Greece and other countries. Although the demand for imported membranes in the flower industry has increased in recent years, it is still in the small-scale trial stage.
The second type used as a covering material is PC solar panels, whose scientific name is polycarbonate (PC) panels, which are currently widely used as greenhouse covering materials due to their good light transmittance and heat preservation.
Most companies have made great efforts in the production and design of solar panels in terms of light transmittance, heat preservation, anti-fog drop, safety, durability, etc., especially in the anti-fog effect, high light transmittance technology and technology, not only can Reflects the quality of the sunshine board, and can better reflect the technical level of the production enterprise.
In addition, high light transmittance is an important feature of PC solar panels. The yellowing of PC solar panels directly affects the light transmittance, while the brittle PC solar panels are damaged by the original Goshen greenhouse under external impact. In order to protect the main structure of the PC solar panel from damage and avoid excessive aging, the manufacturer co-extruded a layer of anti-ultraviolet protection layer (UV layer) on the surface of the panel. The protective layer is made of a polycarbonate-based The materials are co-extruded on the PC sun panel.
The price of accessories and sealing materials required for the glass greenhouse is relatively high. At the same time, due to the high quality, the frame load increases, and the amount of the frame increases accordingly, so the overall cost is relatively high.
