The Halliburton tank car announced by Rapido Trains was transporting cement in bulk, right? The FreightMaster depicted on the side is a cusion device that prevents cargo from shifting inside box cars and refrigerated cars. I wonder if this is effective for bulk transport.
FreightMaster:
https://www.wabteccorp.com/freight-car/end-of-car-systems/cushioning-units/freightmasterr
Reasons might include a free-surface effect of the pulverized material if a cylindrical hopper is not completely full.
Thank you for your comment, @Woke_Hoagland.
This reminds me. FreightMaster was developed by Halliburton around 1960 (History of Halliburton Company – FundingUniverse). I was surprised to learn that it is now a Wabtec brand.
Page 681 of Car Builders’ Cyclopedia 1966 edition
Also, after studying free surface effects and slosh dynamics, I learned that they are issues not only with liquids, but also with powders and granular materials.
Those are definitely some interesting looking cars. I remember seeing a picture of one in a section in Model Railroader back in the mid 90s. From what I’ve read about them they were used for hauling special oil well casing cement.
The hoppers certainly look like those on Halliburton oil field cement trucks, however my understanding is that they source their cement from local cement producers. I live in the Northern Michigan oil producing area, and I only remember seeing a single similar car once or twice. While Class A cement might be obtained locally, Class H cement which is used in deeper wells might be brought in. Also many additives are also used in the cement. One of the most common is bentonite, but the cars I see from trains out of the Wyoming mining area are non descript covered hoppers.
Bentonite is highly hygroscopic. By itself this just poses problems of caking and swelling in transit, something perhaps remediable with car vibrators. But combined with cement in dry mixture, you’d want a car with good seal to atmosphere, and perhaps optimal hopper geometry, because the cement will begin to react with any moisture…