Introduction

The warming up of cargo tanks is performed in preparation for an upcoming dry dock. This operation is carried out after the tanks have been emptied using the spray pumps. The primary objective is to make the tanks free of liquid and to warm the LNG vapor inside the tanks.

The process is conducted using the high-duty compressor (HD compressor) onboard. The vapor is pushed from the HD compressor to the LNG heater, where the temperature increases. The warmed vapor is then reintroduced into the cargo tank from the bottom, ensuring that any remaining liquid also evaporates.

Exercise Overview:

1. Initial Setup:

• The exercise begins by preparing the necessary equipment, including the HD compressor and the warm-up heater.
• The required pool pieces need to be inserted correctly, and the valves must be opened to establish the proper lineup.
• The generators must also be prepared accordingly.

2. Assessment Process:

• The assessment starts when the HD compressor is activated and the temperature rises in the warm-up heater. The user must successfully achieve 40°C at the warm-up heater outlet temperature.
• During the Assessment, the user must also maintain the cargo tank pressure within the prescribed limits, as outlined in the milestones.

3. Completion Criteria:

• The exercise is considered complete when the user successfully achieves the required temperature and maintains the correct tank pressure.

4. Evaluation:

• The final evaluation is based on how the user responds to various remarks, Cautions, and alarms presented during the course of the exercise, as well as their ability to navigate the procedure efficiently.