From the beginning, onboard refrigeration has been the backbone of our business, whether it is service of existing systems, replacing of old R22 systems with new NH3 systems or design and delivery of new NH3 systems for newbuilding’s all over the world.
In the last four years Frost has delivered freezing and cooling systems for 14 new fishing vessels, both factory trawlers and wet fish trawlers, where efficiency and safety have been some key factors in the design. Frost has developed its own control system for the traditional NH3 pump system to ensure maximum efficiency at all times. The control system is operated by a Siemens PLC and connected via Profibus/Modbus or Ethernet and can be monitored or controlled by a PC from any location. The system quoted for this project is a NH3 pump system with economizer.
Care is taken to keep the Ammonia charge on the system at a minimum.
All pipes and fittings outside the engine room are stainless steel 316.
The refrigeration pipes will be run through the cargo hold and enter the Skaginn 3X freezers up through the deck, directly in to the freezers cabins, where the valves for automatic operation are located. This increases safety by eliminating any ammonia pipes from the factory deck. The system can run a RSW system to provide refrigerated seawater for the processing area.
The cooling of the cargo and packing hold is done by a NH3 / Tyfoxit pump system with coils in the holds.
This ensures a stable temperature of -30°C in the holds and increased safety for both crew and cargo as no ammonia is circulated through the coils.