Section 11 Acceptance trials

11.1.1 On completion of construction, the acceptance tests prescribed in Pt 6, Ch 3, 11.3 Acceptance tests 11.3.1 are to be carried out to verify the correct functioning of the installation and its ability to maintain the lowest notation temperature conditions required for the assignment of the intended class notation. The proposed test schedules, which should include methods of testing and test facilities provided, are to be submitted for approval before these acceptance tests are started.

11.2.1 The insulated envelope of refrigerated cargo ships and, where applicable, fish factory ships, fishing vessels, fruit juice carriers and container ships is to be scanned using a thermal imaging camera. The main purpose of carrying out the infra-red scan is to verify the efficiency of the insulation system.

11.2.2 During the course of, or prior to, the acceptance trials all inner insulated surfaces, including tank tops, bulkheads, `tween decks, insulated hatches, coamings and weather decks are to be subject to an infra-red scan.

11.2.3 Where internal obstructions preclude an internal scan, it is to be carried out externally.

11.2.4 The scan is to be conducted with the `tween deck and main holds in total darkness and with air coolers/cooling grids isolated and all heat sources disconnected. The temperature difference, cargo hold to ambient air or sea-water temperature, is to be 15 K or more.

11.2.5 Any deficiencies or abnormalities revealed are to be investigated and repaired to the extent considered necessary by the Surveyor.

11.3.1 The acceptance tests (see also Pt 6, Ch 3, 11.3 Acceptance tests 11.3.2 and Pt 6, Ch 3, 11.3 Acceptance tests 11.3.3) are to comprise the following:

1. Verification of control, alarm, safety and refrigerant detection systems.

2. Test simulating failure of selected components such as compressors, fans and pumps, to verify correct functioning of alarm and systems in service.

3. Verification of accuracy, calibration and functioning of temperature control, monitoring and recording instrumentation.

4. Verification of air cooler fan outputs running at maximum speed, and air circulation rates and distribution arrangements in individual refrigerated spaces or chambers. The latter is to be undertaken firstly with all coolers in operation and secondly with any one cooler or fan out of action.

5. Verification of air refreshing and heating arrangements.

6. Verification of personnel safety devices and warning systems in refrigerated spaces.

7. Refrigeration and thermal balance tests to demonstrate the capability of the combined refrigerating plant and insulation envelope to maintain the lowest notation temperature to be assigned.

8. Refrigeration tests for refrigerated container ships carrying `porthole' type insulated containers. If the prescribed thermal balance tests cannot be carried out due to the number of insulated containers available in the shipyard being inadequate, then, alternatively, the following separate tests will be accepted:

   1. Compressor capacity test.

   2. Duct heat leakage test on at least 20 per cent of the insulated ducting selected at random.

   3. Cell heat leakage test.

9. Thermographic scan to be carried out as required by Pt 6, Ch 3, 11.2 Thermographic survey.

11.3.2 Where a number of identical installations are constructed for the same Owner and by the same shipyard, the refrigeration and thermal balance tests required in Pt 6, Ch 3, 11.3 Acceptance tests 11.3.1.(g), need only be carried out on two of the series, provided the results are satisfactory.

11.3.3 Where the cells of `porthole' type insulated containers are not insulated, a heat leakage test will be required on the first ship of the series only.

11.4.1 Where the class notation includes the symbol ‡ for the carriage of fruit, or the symbol ‡ is to be assigned to a fishing vessel the following records are to be kept during the first loaded voyage:

1. Refrigerated cargo or container ships:

   Refrigerating machinery logs and temperature records for the refrigerated cargo spaces or containers, demonstrating the installation's capability to cool down the full cargo of fruit and maintain the notation temperature conditions.

2. Fishing vessels:

   Refrigerating machinery and freezing equipment logs and temperature records for the refrigerated cargo spaces, demonstrating the installation's capability to freeze the catch and maintain the notation temperature conditions.

11.5.1 On completion of the tests prescribed in Pt 6, Ch 3, 11.1 Tests after completion, two copies of the test schedule for the refrigerated cargo installation, giving details of all recorded data and thermal heat balance results, signed by the Surveyor and Builder are to be provided. One copy is to be placed on board the ship and the other submitted to LR.

11.5.2 At the end of the first loaded voyage a copy of the logs and temperature records requested in Pt 6, Ch 3, 11.4 Sea trials 11.4.1.(a) and Pt 6, Ch 3, 11.4 Sea trials 11.4.1.(b), as applicable, signed by the ship's Chief Engineer, are to be submitted to LR.