Twistlock

In Indonesian: Twistlock (kunci sudut kontainer) Updated November 5, 2026

A twistlock is a locking device inserted into a container's corner casting and turned so the box locks onto the one below, onto the ship's deck or onto a trailer chassis. Types include manual, semi-automatic (SATL) and fully automatic twistlocks that release when a crane lifts the box. Unlocked or damaged twistlocks are a common cause of containers lost at sea or sliding off trailers, so drivers and terminal staff should confirm all four locks are engaged before the vehicle moves.

Lashing
Lashing means securing cargo so it cannot shift under the accelerations of a sea voyage or a road journey.
Container Trailer (Chassis)
A container trailer is a semi-trailer chassis pulled by a tractor unit to carry containers, locked by twistlocks at all four corners.
Quay Crane (STS Crane)
A quay crane, or ship-to-shore (STS) crane, is the large gantry crane on the berth that loads and discharges containers.
Stowage Plan
A stowage plan is the planned position of every container or cargo unit on board a vessel, built by line and terminal planners before the ship berths.

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Vessel stowage

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