n arpex H2-DV-20-D Helical gear Reduction Boxes H2

Flender/Flender Gear Units/Helical gear Reduction Boxes H2

and Electronics Industry (ZVEI) proposed that the question be examined whether mixtures of R1a and R1a - which, on the one hand, are less easily ignited than pure R1a and, on the other hand, have less global warming otential than pure R1a - are suitable as substitute for R1, partic- ularly in domestic retgerators and freezers In this context, the following essential pro erties in terms of refrigeration technologywere to be studied in mixtures of R1a and R1Pa within the framework of this research project - Thermal and chemical stability, also in combination with various materials and the - Combustion properties, the ignition range in mixtures with air, required ignition energy - Thermodynamic properties of importance for refrigeration applications (vapour pressure, compressor oil and minimum ignition temperature phase equilibrium, critical state variables, real mixing behaviour in the gas phase) - __ 2. Results ) The thermal stability of the pure refrigerants R1a and R1a, and also of an equimolar mixture of the two substances, was tested by heating these refrigerants in stages at high pressure (approx 5 bar) in an empty special steel container, in combination with various material samples, and in combination with suitable com lessor oil (pol olester) and maintaining them at constanrtemperature fvor several days in each case Incipient decom osition was established by detection of decomposition products (HF, HC1,alcohols and alghydes, oligomerisation products) in the concentration range from few ppm to approx 1 ppm - - - 2 6 In the presence of all the materials of commercial compressor, but without compressor oil, R1a is considerably more stable than R1a or an uimolar mixture of R1a/ R1a. The limit temperature at which noticeable traces of $ decom osition products occur after three to six days is 1 to 2 OC for R1a, apgrox. 1 ' for R1a and approx. 1 ' for the mixture (for comparison: R1 = 1 ). In combination with the compressor'mat