In the highly competitive market for refrigerators, OEMs want to maximize the utilization of their systems to remain competitive. They need to improve manufacturing productivity and shorten cycle times. One important production step is foaming of the housing with rigid polyurethane foam. Faster demolding is essential to accelerate this process.
|The new PU system results in significantly reduced post-expansion and enables very good process productivity compared to foams of the previous generation.|
At K 2019, Covestro (Booth A75 in Hall 6) will be presenting new polyurethane systems which enable up to 20 percent faster demolding of refrigerators with standard wall thicknesses. The new systems based on optimized polyols, isocyanates and catalysts not only accelerate production, but also enhance the good insulating efficiency of existing rigid polyurethane (PU) foams.
"With the development of this polyurethane system, we are helping the appliance industry master one of its most important challenges," explains Reinhard Albers, an expert for refrigerator insulation at Covestro. "Manufacturers can process the system on their production lines without having to compromise on quality features such as energy consumption or housing geometry," explains Albers.
About 20 percent of the energy consumed by buildings is spent on the operation of cooling appliances. Rigid polyurethane foam offers very good insulation – so it has been used for many years to efficiently insulate almost all refrigerators worldwide. Continuous improvement of the insulation performance means that appliances of the highest energy efficiency class A+++ can now be manufactured. They make a contribution to reducing energy consumption and CO2 emissions and conserve fossil resources. Efficiently insulated refrigerators protect food from spoilage and contribute to a sustainable diet.
The expansion of the foam after demolding is a fundamental feature of PU rigid foam, which influences both the processing and insulating performance. The new PU system results in significantly reduced post-expansion and enables very good process productivity compared to foams of the previous generation. The system has excellent flowability during manufacture and ensures homogeneous density distribution of the foam in the refrigerator housing. This enables the production of energy-efficient refrigerators at low cost using established foam processing technologies.