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By Fred McCague
Every day, container ships slip out of ports on the West Coast, sailing westbound across the Pacific. Some will travel southerly routes, but many are on the great circle via Unimak Pass and the Bering Sea bound for Japan, Korea, Taiwan or China. In December, they are all likely to face a series of winter storms before reaching their next ports.
Virtually all of the ships carry huge deckloads with containers stacked up to six high. While the possibility of losses exists, factoring in the weather and quick turnarounds in port, it is highly likely that all of the ships sailing in December will reach the Orient with their deckloads intact.
Lashing is the key to keeping these containers safe and secure across the Pacific. In the rare case of loss, it is more likely to be caused by the collapse of the container than the failure of the lashings.
P&O Nedlloyd's Newport Bayis a fairly typical example. The ship is a seven-year-old 960-foot maximum length Panamax vessel carrying 4,000 TEU. In the Grand Alliance PNX service, the ship called on Seattle, Vancouver and Oakland in November. Newport Bay'sdeck load is 13 wide and five high, and, the ship can carry empties on the sixth tier.
Chief Officer Eric Harrison explained the lashing system in detail. The first tier on deck is locked to the hatch covers with manual twist locks on each corner of the container. On the second tier, semi-automatic twist locks are placed on the bottom corners of the container by longshoremen on the dock. When the container is dropped onto the first tier container, the pins slot into the top of the box and the force automatically springs the bottom pin locking it into place. Longshoremen on deck then place steel bars into the fore and aft bottom container posts, and with turnbuckles tie the box firmly down to the hatch cover or deck.
For the third tier, semi-automatic twist locks are again placed in the bottom corners on dock, then the container is lifted on board and locked into place. For this tier, only the outboard container is tied down with a steel rods. All of the other boxes are held only by the twist locks. On the fourth and fifth tiers, twist locks put in place on dock are used, but, no other tie-down gear is employed.
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