Refrigerating system compressor unit for ships
RECIPROCATING - K - WA - L
The refrigerant system design may vary from dry expansion of the refrigerant, flooded and pump circulation-, to indirect systems.
For larger installations, the refrigeration machinery can be arranged as a 2 stage cascade system using ammonia (NH3) as refrigerant at the high stage (primary) side, and carbondioxide (CO2) at the low stage (secondary) side. Such arrangement may obtain system temperatures down to -50C and thus reduce freezing time and increase the freezing capacity.