Container Configurations for rail movment?

[CatFoodFlambe]

Some questions about stacking containers for rail movement:

Do the railroads have to consider weight when double-stacking containers, such as keeping lighter loads on top of heavier loads? 

Can 20-ft single-TEU containers be stacked vertically?   I can't recall having seen them in this configuration, but then again their use away from port cities is somewhat limited in the US.   Would a well/flat car need to have a set of cap-lock ports in the center of the platform to allow for this?

Tank container units - will the  framework support a loaded container stacked on top of the tank unit?   Can a loaded tank unit go on top of another container, or does the liquid "slosh" generate enough sway to present a danger?   

Other constraints?   

It would be interesting to understand of all the planning that goes into assembling trainload of containers, particularly if a number of the cars will have to be "fileted" for single-level moment in the east.  Or - do the ports just slap 'em down by destination and let the railroads "rubber sort" them in, say, Chicago or sort them at a center such as CSX's port at North Baltimore, OH?

 

[BaltACD]

If you get the opportunity - check out the gross weight allowed that is stencilled on each container - SURPRISE - the maximum allowed gross weights will be within a few hundered pounds of each other - no matter if you are looking at a 20 foot, 40 foot, 48 foot or 53 foot.  Container operate on surface highways and must comply with allowable loading regulations for highway movement.

Loading of containers, like all other forms of shipment, are dependent on if the load weighs out or cubes out.  Shippers will use the container that best fits their commodity.

Container loading personnel will know if they are handling a loaded container or a empty container.  They won't necessarily know how close to the load limit and particular container has been loaded.

[mudchicken]

Most Mi-Jack straddle buggies, except the older ones, can weigh and monitor sea- can weights  and eccentic loads. The terminal process of accepting a load and weighing the things has a whole series of checks in the container ports. Except for data entry errors, finding a sea-can with a wrong weight sets off all kinds of red flags.

[erikem]

Anything that hints that the contents of the container do not match what's on the manifest will definitely attract the attention of Customs.

[carknocker1]

They do consider weights and it is prefered to have heavier loads on the bottom but not necessary . As far as stacking 20 foot containers on end there is no real way to load and unload them this way

[Wizlish]

A couple of observations I have not seen explicitly addressed --

You can't put two 20' containers on a 40' container, but you can easily do the reverse.

It's common to see 53' containers on top of 40' containers in 40' wells - this uses the 'empty' space over the ends, but not the extra space between 'A' platform ends of articulated units.

As far as I know, the tank units are reinforced to 'sea' standards which are more rigorous than mere double-stacking where the load must be kept effectively upright to prevent tipover on standard-gauge track.

[MidlandMike]

ISO 20' and 40' containers only have the load bearing stacking corner casting, as the name would indicate, at the 8 corners of the container.   So while a 40' container could be stacked on two 20' containers, the reverse is not true.  There are no middle castings on a 40' container to secure or support the adjacent ends on two 20' containers on top of it.  All containers larger than 40' have their stacking castings inward of the ends to match to 40' standard.