|There are 3 weight measurements that are important. Rating, Tare Mass and Payload. These are marked on the container wall, usually on the door in the case of an end-loading dry cargo container.|
Rating is the maximum permissible weight of a container plus its contents. The Rating of a 20' dry cargo container is 24,000 kgs. (52,900 lbs.) and a 40' - standard or high cube - is 30,480 kgs. (67,200 lbs.).
Tare Mass is the weight of the empty container. This can vary with the different construction techniques and materials used in the individual container. A 20' x 8.5' dry cargo container generally weighs between 1,800 kgs. to 2,400 kgs., a 40' x 8.5' generally weighs between 2,800 kgs. and 4,000 kgs, and a 40' x 9.5' generally weighs between 3,900 kgs. and 4,200 kgs. The reefer (refrigerated container) generally weighs more than a dry cargo container of the same size.
Payload is the maximum permitted weight of the payload, including the dunnage etc placed in the container. Therefore,
Payload = Rating - Tare Mass
If the Tare Mass of a 20' dry cargo container is 2,400 kgs. and a 40' is 3,900 kgs., the Payload of a 20' is 21,600 kgs. (24,000 kgs. minus 2,400 kgs.) and a 40' is 26,580 kgs. (30,480 kgs. minus 3,900 kgs.).
There are 3 important points regarding containers that are near their weight limit:
· Careful planning is required prior to container loading. The exact Payload weight is not known until the container passes over the weighbridge at the entry to the container terminal. An overweight container will be denied access to the container terminal, requiring extra drayage, unloading and re-packing costs and possibly storage and other fees.
· In addition to the Rating limit there are road transport limits which vary throughout the world and even within the same country.
· In addition to total road weight limit, road transport authorities may also have weight limits for individual axle weight, so that even weight distribution throughout