I was wondering why some container trains have well cars that are single and double stacked. Lets say a container train has two 5 unit sets that are single stacked. Wouldn’t it be better to put the 10 containers on one 5 unit set than two sets? An answer to my question will be greatly appreciated.
It’s possible that the individual containers are loaded to their max weight, and that stacking them would overload the car. Consider that the ‘inner’ trucks of an articulated well car each carry the equivalent of the gross weight of one articulated section. If double-stacked, that’s the weight of the carbody half-way to the next truck in each direction, plus the weight of two containers (if they are uniformly loaded) - boxes plus lading.
It is also possible that there is some point along the route where overhead clearance is insufficient for stacked containers. If they are 10 feet high instead of the more usual eight, that is a distinct possibility.
Chuck (modeling Central Japan in September, 1964)
Another possiblity may be that if the car is being set out at an intermediate terminal, or connecting to another train, there may not be enough containers going to that terminal to fully load the car.
Ericsp has the right answer. It has to do with where the containers are going. While it might seem from trackside there are 10,000 containers moving every day in solid blocks from a West Coast port to Chicago, in reality those containers scatter to a few dozen ramps. Moreover, a ship calling at a West Coast port is not unloading 10,000 containers all destined for the same place. It unloads containers destined for perhaps 50 rail-served and hundreds of local truck-served points. Neither the port, the railroad, nor the shippers can afford the space or the time or the equipment time it would take to consolidate all the Chicago containers onto one train from four or five ships, and all the Memphis containers onto one train from 10 or 11 ships, and so forth. The idea is to load them up “mine-run” and get them out of town and sort them out en route. The Chicago street and highway system is actually the world’s largest container sort yard: the containers come in on one train, sort into another container terminal on rubber tires via the street system, and voila, a sort yard built on someone else’s land and maintained by someone else’s money. Thus you see cars loaded with five containers single-stack. You cannot load ANY second-level containers until the car is fully loaded on the lower level. Also, it doesn’t mean that the car is being wasted; the yard at the other end may need the extra space when the car arrives. Theoretically you could sort out the cars where you had a three-well car in there but that takes time, money, and space. Ideally every train is fully profiled, i.e., every slot holds a can on both levels, but that takes tremendous volumes to make that economically possible.
Double-stack cars in the U.S. will accommodate containers loaded to their maximum gross weight and then some; the current generation of cars (with the 125-ton trucks at the articulation points) will a
Thanks to everyone who posted an answer. I appreciate it.
I live in Philadelphia and the clearences are a major issue. When I go out to rail fan, in some area’s they can run double stack because there are no tunnels but in other area the cant because of the clearences. Most of the reason is clearences on the route. It is the same reason why Amtrak doesn’t use Superliners in the Norttheast. The old Pennsy lines, Reading, and other lines, were made for low clearence cars, not double stacks or other cars.