Main Types of Insulation Plate for Cold Storage
The main function of the thermal insulation board is to prevent the heat from entering the cold storage. Besides the refrigeration system, the important source of the cold air is the thermal insulation board. The heat transfer of the protective structure and insulation layer of the cold storage accounts for 20% to 35% of the total heat load of the cold storage. Therefore, reducing the thermal load of the protective structure can achieve the effect of energy saving. The cooling consumption of the cold storage through the protective structure is proportional to the unit heat flux of the enclosure structure. In order to reduce the unit heat of the protective structure, one is to select the insulation material with low thermal conductivity, and the other is to increase the thickness of the insulation layer. However, with the increase of thickness, the price of materials will also increase, and there will be problems such as increasing construction costs and reducing space for use. Therefore, thermal insulation materials should be selected within the appropriate thickness range.
When choosing insulation materials, we should first refer to the internal factors of low thermal conductivity and hygroscopicity, and also consider its manufacturing cost.
Before the 1980s, rice husk, cork, slag and expanded perlite were commonly used as heat insulation materials in cold storage. After the 1980s, new heat insulation materials developed rapidly. Rockwool, glass wool, polystyrene foam and polyurethane foam were more and more widely used in society, and construction methods were also varied. At present, polystyrene cold storage insulation board, extruded polystyrene cold storage insulation board and polyurethane cold storage insulation board are widely used. The following focuses on polyurethane cold storage insulation board.
Polyurethane Foam (PU)
The bubble structure of polyurethane cold storage insulation board belongs to closed cell foam material. It is almost unconnected. At room temperature, the static water absorption rate is very low. Among the major thermal insulation materials, polyurethane cold storage insulation board has become a thermal insulation material for cold storage because of its small thermal conductivity, low water absorption, high compressive strength and high durability. The disadvantage is that the material price is relatively high, but it is found that the comprehensive operation cost of polyurethane insulation material is low from the overall balance of economy. Polyurethane cold storage insulation board, there are two forms of polyurethane field eruption and polyurethane cold storage board. The former uses polyurethane in-situ layered spraying, which can achieve seamless seamless seamless seamless seamless seam, strong bonding with the bottom, good thermal insulation, but need to do moisture-proof layer and protective layer. Moisture-proof coatings can be made of new polymer waterproof coatings. The protective coatings can be built in civil form or enclosed with metal sheets. The construction period is long and the construction is complex.
The polyurethane cold storage insulation board has good rigidity, high strength and compact structure. It can avoid damp-proof layer. However, it is necessary to do a good job of joint density, fast installation, short construction period, simple construction, beautiful and hygienic inside the cold storage.
The above products can not only be assembled and used separately, but also be combined according to specific conditions. Polyurethane cold storage insulation board is more suitable for wall and top insulation materials of cold storage. Its thermal insulation performance and durability are superior to other materials. Extruded polystyrene foam plastic is ideal for ground insulation of cold storage, and its thermal insulation performance and compressive performance are more prominent. Therefore, when choosing thermal insulation materials, we should not only select suitable materials, but also conduct comprehensive analysis.
There are many manufacturers of thermal insulation materials, but the quality of products is high or low. Therefore, in cold storage construction, manufacturers with high quality and good reputation should be selected. At the same time, the thermal insulation materials used in construction should be spot checked and tested to ensure the quality is qualified.