In oil, gas and petrochemical industries in services that the fluid temperature is below 0 °C, it’s been used cold insulation in order to maintain the temperature. major constituent component of these insulation's is rigid polyurethane foam that production as ASTM C591 ,which must have at least 90% Closed Cells for better efficiency and it’s divided into two categories based on the type of product and used methods.
Classification by use:
- IN SITU EXPANDED
- Slab Stock
Classification by product type:
- PUR
- PIR
The responsibility for these materials in addition to maintaining fluid temperatures, is preventing the metal surface from freezing. Because if Closed Cell nature of these materials is lower than the minimum required increases heat loss and cause to the process problems in time lapse due to moisture penetration into the insulation and the subsequent freezing of water on the metal surface.
PUR insulation (polyurethane):
Polyurethane foam is made by combining two main ingredients a polyol and an isocyanurate, in approximately equal parts (in the presence of catalyst and blowing agent).
PIR insulation (polyisocyanurate):
Polyisocyanurate chemistry differs to the PUR where it is produced using an excess of the MDI component. This excess MDI is made to react with itself through the use of an appropriate catalyst to form isocyanurate. The index of polyisocyanurate foam insulation products today is about 250. This means that the amount of isocyanurate is 250% of that needed to react with any polyol used; the extra 150% makes polyisocyanurate and minor amounts of other polymers.
The following are the benefits of polyurethane insulation is dedicated to all:
- Low weight & high strength
- Minimal absorption of moisture
- Use ability in the wide range of temperature
- Reduce the allergy problems
- Minimum thermal conductivity compared to other materials
- Thermal conductivity small changes according to the time
- Low increase heat transfer coefficient with increasing density
- Due to the heat transfer coefficient is the highest energy saving
- After contact with direct flame is ignited with much delay & with the retardant is immediately extinguished (Fire Retardant)
So my company to provide better service to my clients is ready to supply preformed cold insulation or injection from famous international Company .