London Ship Managers (LSM) made substantial savings across its fleet of 9000gt refrigerated cargo vessels following an extensive refrigerant plant optimisation programme carried out by Oceanic Technical Solutions.

An engineering team from the Asia division of the UK-based refrigeration specialist carried out complete marine refrigeration inspections aboard the Cala Portese, Cala Piana, Cala Pevero and Cala Piccola.

LSM Technical Fleet Manager Mike Seymour said: “We found we were spending substantial time and resources looking and checking for gas leaks which were still not being efficiently detected, in order to try and remove any environmental impact our vessels were making. This, along with losses of refrigerant obviously had a monetary impact, which we also wanted to reduce.” We operate large direct expansion-type reefer plants, with a substantial amount of pipe work penetrating decks and bulkheads, so gas monitoring and detection is a highly complex task for us.
“We transport bananas and pineapples so maintaining a 13.3°C temperature is crucial to our operations. If we lose refrigerant, not only does it result in unnecessary expenditure, it puts undue stress on the compressors and it could result in cargo loss. Although our vessels operate outside of European F-Gas rules, its good practice to ensure our ships operate in an economically and environmentally-sustainable way.”

Taking just three days to inspect the entire plant on each ship, the Oceanic Technical Solutions team carried out a full system evaluation and performance test, finding substantial gas leaks from corroded pipe work in bulkhead penetrations.

Dave Lloyd, Oceanic Technical Solutions’ Technical Director said: “Two of the vessels were found to have major refrigerant leaks, but they had proven very difficult to find. You get a lot of moisture building up around insulated pipes and bulkhead penetrations and this can corrode the pipe work, resulting in substantial refrigerant loss.”
Once Lloyd’s team found the source of the leaks, the plant was shut down and isolated so repairs could take place. Additional isolation valves were fitted and when the plants were running to optimum, shipboard crews were shown how best to carry out routine inspections.

“The catalyst for inspection was to reduce the amount of refrigerant being used and to prevent gas escaping to the environment. We achieved that,” said Lloyd.

While LSM has made annual savings of about 15% year-on-year with replacement of refrigerant cylinders, frequent refrigeration inspection and optimisation prevents compressor wear and tear and increased loads on generators as they compensate for systems with reduced refrigerant.

“Oceanic got our refrigeration plants back to their design specifications. The savings we have made in refrigerant costs alone have more than paid for the cost of inspection and maintenance,” said Seymour. “That’s a very good return on investment.”

Robert Chesters, Oceanic Technical Solutions’ Managing Director, added: “With vessel movement and vibration, it is inevitable that refrigerant leaks will occur, with seals breaking down and valves coming loose and so on; but the key is to carry out frequent performance tests and to keep on top of the maintenance. Simple measures, such as regular oil changes, replacing filters and tightening valves and flanges, can make a huge difference.

“LSM has shown that even though their vessels do not fall under the F-Gas regulations for mandatory inspections they have taken control of refrigerant consumption and the overall impact of operations on the environment. This is responsible ship management.”