Newbie questions on coal gondola vs hopper

[Anonymous]

Relative to cars hauling Power River Basin coal, what are the major differences between "Gondolas" and "Hoppers"? At times the terms seem to be interchangeable. Do all gons have solid bottoms? Can hoppers be used in service where the cars are unloaded by rotating?

[Anonymous]

I can't testify as to which names are correct since everyone seems to have their own terminology for different things.... I can tell you that bottom dump hoppers can be used in a rotating car dumper as long as they have the rotating couplers. The power plant I work at uses air dump hoppers, but they can be, (and have been) used at our other station that uses a rotary dumper. I believe they have to pin the doors shut on them to prevent any unplanned opening of the doors.

[mvlandsw]

Hoppers or gondolas without rotary couplers can and are used in rotary dumpers. They are uncoupled and dumped one at a time.

[waltersrails]

ditto

[Anonymous]

Dinjohn--

Welcome to the forums![#welcome]

The difference between a hopper and a gondola is that the hopper has a sloped bottom so that it discharges using gravity through sets of doors built into chutes in the bottom, and a gondola has a flat bottom.

In a standard hopper car, the ends are sloped, and there may be sloped dividers between several hopper compartments (each with its own set of chutes and doors on the bottom). Generally, when the load is dumped the car is "self-clearing", i.e., the entire load dumps by gravity. Sometimes this needs help, particularly in the winter when loads freeze, so there are thaw sheds and car shakers that can help a balking load to empty. under those conditions

Some older gondolas have had doors in the flat bottom. These are usually referred to as "drop bottom" cars. These were usually utilized for sand and gravel service. They are not self-clearing. When the load was dropped through the doors, a worker with a shovel usually had to go into the car and push out the remaining load through the doors. Obviously, these cars do not haul Powder River coal.

Both gondolas and hoppers can be rotary dumped, but hoppers without a rotary coupler at one end must be uncoupled individually. For high volume unit train service where rotary dumpers are utilized, the cars (gon and/or hopper) are equipped with rotary couplers so the train can go through the dumper as a unit without uncoupling.

Hope this info is useful.