Could someone point me in the right direction of what type of cars would be used for unit trains of crushed rock in, say the late 1980s - early 1990s?
Locale would be Central Texas and it would be for a freelanced Class 1 bridge line, comparable in size to the DT&I.
Also, thoughts on typical motive power for the rock trains? So far, I've planned that the railroad has typically been a 4-axle road (big buyer of GP30s and GP40s in the 1960s, and then GP40-2s over the next decade), except for a few SD40-2s built to Burlington Northern specs for pool power on coal trains destined for power plants along my line. But what would've been typical for rock trains in this time period?
Thanks!
Dakota
The SP had 3 basic types of equipment for their Texas rock trains, gons (52 or 65' ft mill gons), OJ's (the PRR style solid bottom gon ore jennies) and hoppers (100 ton twin hoppers). The MP had 52 or 65 ft solid bottom mill gons or 100 ton quad hoppers. The GRR, WRRC and mining companies tended to have Ortner hoppers (those with the straight ends and "porches" on both ends).
Generally GP's were used The MP tended to use GP38-2's and B23-7's, sometimes B30-7's. The SP used 4 axle power. The really odd balls were during the CNW merger, the UP had a power crunch and leased anything they could find, they ended up using AMTK F40's on south Texas rock trains. Mostly because they weren't good for anything else.
I worked on the MP in Texas in the early 1980's and the dispatch offices that handled Texas at various times over the next couple decades.
Dave H. Painted side goes up. My website : wnbranch.com
Try checking out a pit operation just south of Georgetown, TX. Used lots of 100 ton Ortner cars and recently gons. Check the web site for pictures. http://www.texascrushedstoneco.com/services/rail-capability/
Also Walthers had the GRR Ortner cars but now out of stock, but their website pic is good.
Dean S May
I am most familiar with the SP's operations serving mines at Knippa, and Blewett on the Sunset route west of San Antonio and, Beckmann on what is left of the Kerrville Branch, northwest of San Antonio, 1978-1986. Since then another quarry has opened at Dunlay, between Hondo and LaCoste TX, but that was a UP thing of the 2000s, so disregard it if you are searching these locations on Google Earth.
To better understand SP's car utilization, you will find SP freight cars are covered by type, class, and number block-your choice, on Lee Gatreaux' (I hope the spelling is correct) SP freight car website at www.railgoat.railfan.net . Lee's site can also be accessed from the Southern Pacific Historical & Technical Association's www.sphts.org. Click on "resources" and then "links" to members websites.
By the 1980s, SP had standardized their aggregate cars on 100 ton capacity units in the gondola and hopper types. This is not to say a 70 ton car didn't show up occasionally, but it was to be avoided as much as possible due to the likelihood of it winding up overloaded. Envision a guy who has been loading 100 ton cars all day, everyday in 100 degree weather for the past month and the 61st car in that 84 car string is only a 70 tonner. Oops! Thats why SP restricted aggregate service cars to the 100 tonners.
Like most railroads, SP had their own internal classification system for their locomotives and cars. The first letter defined the car type. In the case of the aggregate cars, this would be "G" for gondolas and, "H" for hopper cars. The letter would be followed by a two or three digit number indicating capacity in tons. Another number followed the capacity, indicating the numerical sequence of that group of cars of said capacity i.e. G-100-6 or, the sixth grouping of silmilar 100 ton capacity gondolas in number series 345600-345699. When you go to the railgoat site you will find gondolas with 50, 70 and 100 ton groupings. Same for hoppers.
Southern Pacific had 100 ton gondolas in 29', 40', 52'6", and some 65 foot inside lengths, although I doubt the 65 footers were used in aggregate service, even if they were rated at 100 tons. Remember the railroads that hauled ores in regular coal hoppers-how they would load a small pile over each truck, leaving the center of the car empty? The reason was, the ore was much denser in weight than coal and a 70 ton car full of ore might well be overloaded by 2 1/2 times-if it didn't fail structurally first. The same applies to a 65 foot gondola loaded with stone.
Hence the 29 foot, flat bottomed 100 ton ore gondolas of the G-100-1 class cars in the 345000-345599 series, and the G-100-6, 345600-345699 series ore gondolas, built by the SP in their Sacramento shops for serving Kaiser Steel's Fontana, CA works with ore from Kaiser's Eagle Mountain mine. Once Kaiser closed Fontana, these shorty ore cars found work in Arizona and Texas. These cars had solid floors-no doors-so, the consignee had to rotary dump (not likely) or-scoop the lading out. HO models of these cars were made by Roundhouse/MDC before Athearn acquired that line. From time to time, they again become available as part of Athearn's Roundhouse line. Bachmann also has an offering in their line of r-t-r cars.
The G-100 classes include a large number of 52'6" gondolas in the 33xxxx number groupings that are used for aggregate loading. Most of these cars are of welded construction, built by Thrall Car Mfg. Co. They are very close in appearance to the cars offered by ExactRail, Atlas and Walthers. I say close because the SP cars have 13 side stakes, while the Atlas and Walthers cars have 14. As a freelancer, this may not matter to you. At this point, it should be understood, the type of prototype car supplied to be loaded is determined by the consignee's unloading method. It makes no sense-or cents-sending a string of hopper cars that dump between the rails to a consignee that uses a clamshell bucket or a backhoe crawling along the tops of the carsides to unload. You can kiss that customer goodbye! Again, I seriously doubt you would find any cars over 52'6" in this service because of the potential for a catastrophic overload.
Hopper cars in aggregate service on the SP were many, in the H-100 classes. The Walthers two pocket, 100 ton aggregate hopper is a model of a Greenville prototype heavily favored by the SP. Southern Pacific also had at least 350 cars built to the same blueprints by Pacific Car & Foundry in the H-100-32 class. Again I defer to Mr. Gatreaux excellent site to provide in depth coverage and illustration of all the members of these classes. SP also had some twin hoppers that looked like regular, exterior post cars except for their 100 ton trucks and taller sides and ends. Mr Gatreaux also provides reference to articles on the various cars, that have appeared in the model press.
The power to pull these trains on the SP was provided by four axle locomotives and slug sets, in the 1980s. Strangely enough, although these trains were heavy, six axle power was not used because the rigid wheelbase of the C truck was hard on the light rail of the branches. Of course the run from San Antonio to Beckmann on what was left of the Kerrvillle branch was like so many other branch lines. The only time it saw a track gang was when something derailed. The maximum authorized speed according to the employees' timetable was 25 MPH, with a lot of 10 MPH crawling. With speeds this low, SP deduced this would be an ideal application of their coming slug sets. The 20 new GP-40-2 "slug mothers" meant to bracket road slugs to be built from retired GE U25Bs arrived first and were quickly pressed into general road service while Morrison-Knudsen of Boise, Idaho labored on the first slug. Once SP had it in hand, Sacramento selected a dozen U25B hulks from its stash and, got busy fashioning numbers 1601-1612. SP also had eight Cotton Belt GP-40s that had never lived up to expectations, that also became rebuilding fodder. The first 20 GP-40-2s occuppied the 7940-7959 number block while the GP-40s rebuilt to GP-40-2s internally, became 7960-7967.
These slug sets were found wherever the tonnage was high and the speeds were low-the timber branches of northern California and Oregon, the copper country of Arizona, and the rock lines in Texas. They also could show up anywhere along the Sunset route, going to, or returning from any of these regions. If more power was needed than the slugsets produced, grab enough B-B 3000 HP units off of the ready tracks to make up the difference. It is at this point I refer you to www.rrfallenflags.org. Go the Southern Pacific section and select the entry for diesel locomotives, in the 1000 to 1999 number block. Check out the power consists assisting the 1600 series slugsets. As a freelancer, I would use anything from a GP-9 to GP-40-2 due to the rickety track, heavy tonnage, and slow speeds of these operations. If you want more information on the slug sets, I refer you to "Southern Pacific Historic Diesels, Vol. 15", by Joseph A. Strapac, ISBN 0-930742-37-0, covering SP's GP-40s and GP-60s, and all that went on with them.
This was an interesting time in Texas. The Missouri Pacific also served the mine up on top of the mountain at Cline. As a matter of fact, the MP wound up negotiating trackage rights over SP from San Antonio. The all MP routing was about 60 miles farther and most of that was at a maximum of 25 miles per hour, with lots of 10 and 15 miles per hour crawling along. All the MoPac trains I saw had B-B power and consisted of 52'6" gondolas-no hoppers. Most of the gons were MP corrugated side cars but, foreign cars raised no eyebrows either. Bear in mind the Sunset had a 70 MPH speed limit for freights so, you'd best not hold things up!
As NHTX wrote the choice of equipment depended on how it was going to be unloaded.
Hoppers were generally unloaded over a pit, which means a permanent structure. Many of these facilities served ready mix concrete plants and were in locations where there were steady demand for aggregate.
Gons and OJ's were used where the cars were going to be unloaded with a backhoe, either one that crawled across the tops of the cars or was along side the track. Often they served locations that were dedicated to a specific project. Often that was a highway project that might take dozens of trains, but was only going to last 4 or 5 years, so they didn't build a permanent unloading pit. When they built the railroad at Spring, TX in the early 1980's they recieved dozens of rock trains in gons, all of which were unloaded by backhoe.
There were two types of backhoe used. There was a smaller type that was a backhoe.front end loader wheeled tractor with the outriggers and bucket modified to rest on the top chords of the car sides. The other was a tracked backhoe that would just crawl over the loads, unloading behind it.
In both styles it was common to unload down to the last part of the last car. They would leave the car with the backhoe in the unloading facility and then when the new train arrived, they would put the loaded cars on top of the backhoe car and the backhoe would work its way down the line of cars, once again stopping at the last car. This process was used for projects that got a lot of cars frequently. It saved the time and trouble of getting the backhoe on and off of the cars. The rock trains ran on a semi-regular cycle. They often didn't work on weekends or if it rained (the quarry pits would get too muddy).
NHTXBear in mind the Sunset had a 70 MPH speed limit for freights so, you'd best not hold things up!
Sorta. The SP 33xxx series cars were restricted to 40 mph as were the Herzog rock cars. Any empties other than those listed in the special instructions in any train were restricted to 55 mph. Plus it wasn't uncommon at various times for the railroads to put a blanket 50 mph speed restriction on everything except passenger, intermodal and auto trains for fuel conservation. Yes the max speed was 70 in places, but the majority of trains weren't going 70.