Special polyurethane composite material for tank insulation
Summary
As an insulation material, polyurethane rigid foam has an irreplaceable position in many aspects with its extremely low thermal conductivity and convenient molding process. It also plays an important role in saving energy. is of extremely important significance. The food industry in our country is developing rapidly. The demand for polyurethane is becoming increasingly widespread for the insulation of fermentation tanks, storage tanks (beer, wine, condiments) and some low-temperature liquid storage tanks (such as liquid carbon dioxide).
Polyurethane materials used for tank insulation are generally divided into three types according to the molding method: manual pouring type, equipment pouring type and on-site spraying type. They are often selected based on the shape of the tank, on-site conditions, and the habits of the construction team. Proper way to operate.
Since the mold closing method cannot be designed when forming the insulation layer of large tanks (especially the casting type), the necessary closed mold extrusion effect cannot be produced during the molding process. Therefore, the foam molded in a semi-free foaming state often has Inevitable molding shrinkage. If the shrinkage is large or uneven, it will cause the insulation effect to decrease and the appearance to be unsightly. How to strictly control the shrinkage is a crucial part of the tank ingredients and material selection.
Chemical composition and properties
Polyether composite materials used for tank insulation usually consist of polyether, foaming agent, catalyst, foaming agent, flame retardant and other components, depending on the foaming agent The difference can be divided into several main types such as high fluorine type, fluorine-free b type, fluorine-free all-water type, etc.
Usually the polyether composition is in the form of a light yellow or brownish red viscous transparent liquid with no coagulation, thick matter or unevenness, and no mechanical impurities.
Reference process parameters
< r::/r/~/_.
Manual pouring type
Mechanical pouring type spraying type
Milky white time~~
Gel time~~~
Curing time
Overall density/~~~
Note: The above parameters are adjustable according to different conditions and requirements on site. < r::/r/~/_.
Reference performance indicators
Compressive strength (): Water absorption:
Shape stability (℃,): Thermal conductivity: .3/
Packaging, storage and transportation
Packed in dry and clean special galvanized iron drums, sealed and stored in a dry, cool and ventilated place, waterproof, sun-proof and heat-proof. Optimal storage environment temperature:
~℃
.
Precautions for use
① When using foam, it is best to control the temperature of the material within an appropriate range to ensure that the system has appropriate reaction performance and fluidity
② When foaming, the instructions for use should be strictly followed. Determine the ratio of white material to black material to ensure that the process performance of the system and the various basic properties of the foam are not affected
③Do not let the material come into contact with moisture, and please pay attention to proper ventilation at the production site.
Special polyurethane composite material for tank insulation