To facilitate the loading and unloading of the cargo, the bottom of TLS offshore containers is usually designed with fork pockets, which are required as follows:
1. If provided, the fork pockets shall be arranged in the bottom structure with the top closed to penetrate the bottom and prevent the offshore container from overturning from the fork tine.
2. The net opening size of the fork pocket of the offshore container shall not be less than 200mm×90mm.
3. Considering the length, height, width, and rated weight of the offshore container, the position of the fork pocket should ensure the stability of the container when it is transported by the forklift. The fork pockets should be as far apart as possible, generally not less than 900 mm from the center, but not more than 2,050 mm.
4. The bottom plate of the fork pockets can be closed completely, but openings are recommended for maintenance and to reduce the risk of loose items being left in the fork pockets, thereby preventing items from falling during the lifting process. Where openings are provided, the size and position of the opening should be set to avoid jamming or being damaged by the tines The opening at the bottom of the fork pockets are not allowed at the bottom side rails, and the distance between the opening and the bottom side rails should not be less than 200mm.
5. The weakening of vertical shear strength of bottom side rails by fork pockets opening should be taken into account when calculating the bottom side rails strength. In general, a reinforcement plate should be attached to the top of the bottom side rail. The reinforcement plate should be in the same plane as the bottom side rails web. The reinforcement plate should be extended by at least 100mm at both ends. At this point, the weld between the reinforcement plate and the bottom side rail should be completely melted through.