The polyurethane materials used for sandwich panel for cold room thermal insulation are white, black. The foaming process is the same, and the foam is very similar in appearance. However, the difference of the white material will result in a great difference in the performance of the product. Even the use of some inferior white materials will not achieve the effect of heat preservation.
Thermal insulation performance of thermal insulation materials for cold storage:
The first requirement of polyurethane thermal insulation material for sandwich panel for cold room is thermal insulation performance, which can not be observed by naked eyes before it is put into use. It is too late to observe the difference in power consumption. Through a large number of experimental tests, the company strictly controls the selection of materials to achieve this goal:
1. Use structural amine ether to reduce thermal conductivity and improve insulation effect;
2. The moisture content of various raw materials and formulas shall be reduced as far as possible to avoid the deterioration of thermal insulation performance caused by water foaming;
3. Main material polyether: after selecting the products of the big processed factory after strict postprocessing, compared with the polyether of small factory without postprocessing, the foam foams have high uniformity and thin wall of foam holes, and the heat insulation performance is better than that of ordinary foam with thick wall and big holes.
4. The use of highly efficient and tasteless amine catalyst can effectively adjust the balance between foaming and gel reaction, so that the interlayer skin of the sprayed coating is thinner, which is beneficial to the performance of the thermal insulation material of the cold storage.
5. Do not use ordinary polyester polyols. These control measures have achieved quite good results. Compared with several refrigerators at a customer's site in Changzhou, the power consumption of the refrigerators with white materials is significantly lower than that of the refrigerators with white materials from other manufacturers.
Polyurethane foam dimensional stability:
The polyurethane foam in cold storage will change in size when it is subjected to severe temperature change or for a long time at a lower temperature. In addition to the regular performance test of simulation, more attention is paid to the control of the selection of high-quality materials:
Polyurethane cold storage insulation material foam service life:
In addition to the basic performance of polyurethane foam, the deterioration of foam performance is also an important indicator. When the white material is prepared, the surface of some polyester materials can make the foam have better toughness and impact resistance, but it will become brittle after a period of use in the cold storage, and will no longer resist impact and collision.
Besides, the poor hydrolysis resistance of some polyester structure foam will also affect the service life of the foam. It uses the polyether structure, which is brittle at the beginning, but it will disappear after a few days.
Suggestions on the number of heat preservation materials for polyurethane cold storage:
Cold storage investment is a long-term and rewarding investment. The high number of distributors can really reduce the initial investment, but we need to grasp certain limits. We must consider the long-term energy consumption and the initial investment comprehensively, because the thermal insulation effect of the thermal insulation materials of polyurethane cold storage has a parabolic linear correlation with the bulk density. A large number of studies show that the foam bulk density is more than 36~40 kg/cubic meter. It has good heat preservation performance, so it is generally recommended that the number of refrigerators with constant temperature should be 22-23 m3 / T.