Actually, that information is totally incorrect.
Gadfly wrote:I'm not sure I can accurately describe it. They are usually used for high-volume Boxcars where a larger opening is needed for access.
A plug door can be on
any size boxcar, not just high cube cars. And they are not used specifically "where a larger opening is needed for access". Plug doors are used where a
tight seal is needed. Hence the name,
plug door. Many plug doors are not any larger then a standard boxcar sliding door. While many high volume boxcars
have plug doors, it is not a requirement or a nessecity that a high cube box car have plug doors. We used to get monster 89' high cube auto parts box cars that had double standard sliding doors. And NS and BNSF for example have high cube box cars with huge sliding doors. No plug doors.
A plug door is used to keep dust, dirt, wind, rain and weather OUT and the product safe and clean inside. They also allow a higher level of security due to the design of the door. A place you will almost always find plug doors for this reason is on reefers. The Tropican Juice Train is a perfect example of plug door cars. Also high value paper cars, electronics, food products, etc. A normal sliding type boxcar door is not always going to be water tight and definately not airtight. Because of that, you can only ship items that will not be harmed by dirt and moisture or whatever your shipping must be packaged in such a way that it is protected from the elements.
Plug door cars being more complex with their special door sliding and closing/opening arrangement cost more to make and cost alot more to maintain so you don't see as many. Sliding door cars are simpler to build and maintain and the doors are allowed to be open or closed during shipping without any issues. And the vast majorty of "sensitive" items are often shipped in trailers nowadays anyhows, so plug door cars are still nowhere near as commonplace as the traditional boxcars.
Gadfly wrote:They are double doors
And a plug door can be a single door
or a double set of doors. The vast majority are single doors. Double door plug doors are not as common as single doors.
Gadfly wrote:that fit "flush"
They don't fit flush with the side of the car. They simply fit tightly against the side of the car, but definatley not flush.
Gadfly wrote:and are secured by turning a wheel or a multi=spoked handle
On some, yes, but most use a simple "t-handle"
Gadfly wrote:which pulls the doors snugly into the door opening.
Correct. A gear mechanism forces the door against the car.
Gadfly wrote:Sometimes you can spot these doors by looking at/for the handle which is often painted yellow.
There is no AAR or FRA requirement to paint the handle any special color. In most cases, they are simply whatever color the door is. Black on FBOX cars, White on Reefers, etc.