A1G 2320 Series: Center Flow® Covered Hoppers, 55 Foot 4 Bay
Yes, the term "Center Flow" is a registered trademark, originally belonging to American Car and Foundry for their particular type of covered hopper. The center flow refers to how the inside of the car is free from obstructions-- unlike the previously "standard" covered hopper such as that modeled in A1G Series 2310-- allowing for the free flow of lading down through the center of the car. AC&F introduced the Center Flow in the early 1960's, and these models weren't that far behind. They were made by Roco in Austria. After Atlas moved production under its own roof in the USA, it re-introduced updated versions of the car. Atlas has made other improvements since then, and has debuted new versions of the car as well including the Pressureaid type in 2001 and a somewhat smaller version in its "Trainman" line in 2006. And there have also been plenty of other Center Flows of this type produced for marketing by other companies, including Micro-Trains, Intermountain, Bachmann and Model Power, the latter two using tooling much like if not identical to the A1G version.
Note in the above page from the Atlas 1967-68 catalog that first, the cars are listed as "Center Flow Tank Cars" (oops!) and second, they are shown as "coming soon".
One may pooh-pooh some of the "variations" reported in the A1G series, but the 2323 Gulf has one that is pretty indisputable. There are distinct lettering types in these two versions. What I'm calling the "A" variation has the Gulf logo in the form that was probably closer to the real thing, with somewhat compressed "fat" lettering. The "B" variant has taller, thinner more widely spaced lettering and appears to be somewhat more scarce than the "A" version. In any case, you don't need a lot of funds to accumulate this quartet, just a little bit of patience.
Key spotting features for this car are:
Note: The following information on conditions and "Approximate Value" prices are intended to be a guideline only and is presented with no warranties, express or implied. Caution: Definitions and prices can and do vary with collectors, buyers and sellers, and, of course, whether a person is buying or selling an item. That's the way a "free market" works...
A 2320 series covered hopper in "as manufactured" or "AM" condition has:
A 2320 series car in "mint in box" or "MIB," meets all "As Manufactured" criteria plus:
There is no estimated value for "runner" cars in this series.
AV = Approximate Value (US$ range)
AM = As Manufactured (see above)
MIB = Mint In Box (see above)
Abbreviations: Hld=Herald, R/N=Roadname, L/R=Left/Right Side of Car