Saturday, December 12, 2009

REEFER CONTAINER TRANSPORT 2 (BASIC OPERATIONAL GUIDELINES FOR REEFER VESSELS)

An analysis of major claims recently carried out by the Club has highlighted a disproportionate number of cargo claims generated by reefer vessels over ten years of age during the past five years. The findings revealed that approximately 50% of reefer vessel claims occurred due to "Reefer Plant Failure" (40%) or "Electrical Failure" (10%) and almost 40% of the claims were directly attributable to the errors of engineer officers or deck officers. Since the failure of plant can often jeopardise an entire cargo, and considering the valuable nature of the commodities generally conveyed, a resulting loss can be immense.

The volume and magnitude of reefer vessel claims has persuaded the Club to introduce positive measures in an effort to minimise reefer losses. Now that it has been established that most claims have arisen due to the breakdown of machinery, the Club will be introducing a policy whereby all reefer vessels of more than ten years old will be inspected on an annual basis. The inspections will be carried out by specialist reefer surveyors and will be directed towards the reefer plant, ancillary equipment, cargo chambers and those responsible for its operation and use.

This Bulletin has been written for the benefit of those Members who are operating reefer vessels, addressing common problems and offering basic practical advice. Such Members are also requested to place copies on board their vessels for the guidance of their crews.

Operation and Maintenance

Perhaps the most crucial factor in the prevention of reefer claims is the appointment of suitably experienced senior officers. It is considered essential that crew changes do not result in the sudden loss of expertise, particularly if personnel are switched between reefer and non-reefer vessels on a regular basis. At least one senior officer in both the deck and engine departments should have several years’ reefer experience.

The majority of reefer plants are automated to a certain degree. In general, sudden faults are infrequent and are usually preceded by an abnormal deviation or trend. Routine attention to operational matters will frequently highlight such trends. For example:-

• A running log should be kept.

• Logs and computer print-out sheets should be monitored and figures compared at regular intervals to pinpoint any adverse trends.

• Adequate local pressure gauges and thermometers should be installed and marked with approved limits.

• The function of all indicator and warning lights should be understood and recorded, and not simply ignored if activated.

• In manually operated plants, the manufacturers control limits should be adhered to.

• All faults or breakdowns should be recorded, however minor.

• All operations staff should be familiar with the activation of standby plant.

Basic day to day maintenance as well as adherence to manufacturers instructions is essential if claims are to be reduced. User maintenance of automatic and non-automatic equipment must include attention to filters, oil levels, leak checks, the running of standby plant and the monitoring of control equipment. Attention should also be given to any other items noted in this Bulletin. It is also important with fully automated plant that operators are capable of handling the plant in manual mode. Standing instructions concerning the operation of the plant should be posted in the main plant room. A well-maintained and operated generating plant is vital to the safe carriage of reefer cargoes. Attention should also be given to the monitoring of electrical equipment, including the regular recording of insulation resistance (megger) readings.
The general cleanliness of the plant is equally important, and is an indication of the care and interest taken by the ship's staff.

Common Faults

A basic understanding of how the plant functions and the close scrutiny of the plant in operation is important. As already noted, the majority of plant failures relate to abnormal activity for some time before a fault actually occurs.
Some common faults in brine and direct expansion systems are as follows;

• Choked sea water cooling filters.
• Dirty heat exchangers (sea water side).
• Choked filters or pipes in freon/CO2 leakage detection systems.
• Contamination in refrigerant filters after overhaul or repair work.
• Drains from battery coils choked. (This can lead to serious cargo contamination in hot sea water defrost systems).
• Inadequate attention to defrosting, particularly in non-automatic systems. (The compartment battery should be independently inspected before and after defrosting).
• Choked hold bilge suctions.
• Dirty air filters on generators and motors.
• Leaking glands in brine pumps.
• Inadequate sounding of hold bilges.
• Misinterpretation of lubricating oil levels in compressors. (A low level or no show in the sight glass is often a sign that lubricating oil has been pumped over into heat exchangers).
• Slack or missing drive belts in motor/compressor systems.
• Inaccurate, missing or faulty direct reading thermometers or pressure gauges.
• Inaccurate setting of alarm and safety cut-out systems.
• Inadequate replacement of driers in gas systems.
• Failure to retain faulty or replaced components for manufacturers assessment.
• Over-reaction to compartment temper-ature changes. (This is particularly applicable in the case of direct expansion systems).
• Lack of a comprehensive fault check list or chart on board. (Members may seek the Club's advice in this respect).

Spares

In general, Classification Societies no longer specify a list of spares to be retained on board. Societies merely recommend that adequate spares together with the tools necessary for maintenance or repair should be carried. Spares themselves must therefore be selected by the shipowner according to the design of the plant and the intended service. The provision of spares is consequently the responsibility of the owner and the Club considers it essential that Members keep an updated inventory. Except in the case of a planned overhaul, spare parts will only be wanted in an emergency, and then in a hurry. It is therefore most important that spares are clearly labelled and identified, and stored in a safe, clean area.
It is also essential that vessels are furnished with an adequate stock of common consumable supplies. On several occasions the Club has found reefer vessels to be without sufficient reserves of spare refrigerant gas, compressor oil, thermometers, gaskets/joints and spare phials for Draegers.

General Advice

In addition to the foregoing comments, the following sound practices are also important;

• All manufacturers’ manuals and instructions should be provided on board. If necessary, these should be professionally translated into the appropriate language spoken on board.

• Members should place instructions and advice on board regarding the stowage, carriage and constraints of various reefer cargoes. Similar guidance should be given regarding the operation of the plant. These instructions should be updated regularly and recorded as read by joining officers.

• All defects or breakdowns should be recorded and reported to Members.

• Preload checks should be carried out and recorded.

The measures outlined above will, if adhered to, minimise the risk of a reefer claim. The Club's Loss Prevention Officer will be glad to assist any Member in need of further guidance.