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| A new #2 wheelset is indicative that GACX 469523 has been to a RIP track recently. Also note the repositioned reflective striping and the A-end draft key has been painted, both of which likely occurred at the same time as the wheelset was replaced. |
The December 2015 issue of Model Railroader has an interesting article on railrcar repair by Matt Snell. I’d been meaning to write this for a while, so I thought I’d take this opportunity to expand on some of what matt wrote about. My summer occupation for the past number of years has been working in the Fleet department at one of Canada’s largest private railcar owners (I’ll let you do the math on that). One of my primary responsibilities was reviewing, understanding, and to some extent, auditing railcar repair bills, both from home shops as well as those received from the railroads for running repairs made in normal operation of a railcar. As a modeller, I found much of the information, practices, and procedures fascinating but generally unknown to many other modellers. We often tend to focus on locomotives or operations as higher-profile elements of the hobby (anyone else have about one locomotive for every five freight cars on their layout?), but it seems to me that there aren’t many “freight car guys” out there. You know who you are, rivet-counters! I thought I’d try and explain some of what goes into the repair of modern freight cars and how it can relate to model railroad operations.
Background
Any railroad in North America participating in interchange (i.e. almost every one except for QNS&L, isolated railroads not connected to any other, or private passenger carriers) must comply with the Association of American Railroad (AAR) Manual of Interchange rules. Set out in the rulebook (actually comprised of an office manual and a field manual) are lists of correct procedures that ensures safe and fair treatment of a car if repaired by someone other than the car owner. Approved parts, procedures, and correct repairs are covered in rules that apply to specific parts or procedures. For example, rule 36 covers roller bearings, and rule 41 covers wheels. When a railcar, private or railway-owned, operates in interchange it almost certainly travels over multiple railroads, and thus can be expected to be repaired at almost any point in its’ journey. When I say repaired, this may be from damage (e.g. collision), or from normal wear and tear on consumable items like brake shoes and wheelsets (wheelset covers the axle, bearings, and wheels, grouped together for billing purposes). Thus, a standard set of rules is needed to ensure that repairs are made correctly to the car, regardless of where they are performed. In general, except in the event of a derailment (or for some specialty cars including tank cars), a railroad will usually elect to repair a defective car themselves rather than go through the hassle of contacting the car owner and coordinating for movement to the owner’s home or contract shop. Nothing would ever move if every time there was a high-impact wheelset the car was sent to home shop (nor, in most cases, would it be safe to do so). Thus, for certain job codes, blanket approval is provided under the interchange rules for railroads to conduct specific repairs without prior approval from the car owner. In most instances, for example, a high-impact wheel is changed and the car owner billed at the end of the month (all AAR billing is done once a month, at accounting period month-end).
Types of Repairs
The interchange rules cover a wide variety of possible repairs to railcars of many types. Some repairs are common to all types (such as replacement of wheelsets), while others are specific to a car type (e.g. repairing a door on a boxcar). Some defects are detected automatically such as high-impact wheels, where tread defects result in high impact forces when the defect (a small deviation from roundness) collides with the rail surface, resulting in the distinctive sound every time the defective wheel rotates. Automated Wheel Impact Load Detectors (WILD) use sophisticated strain gauges placed on the rail to measure train forces and identify high-impact cars. By knowing the axle number within a train consist, the detection equipment can identify the axle’s position within a train and match it to a certain wheel on a railcar based on reading its’ automatic equipment identification (AEI) tags, which are RFID transponders located on opposite corners of a railcar (2 per car). When a high impact alert is generated, it is reported through Railinc, the AAR’s electronic data interface with car owners, and monitored until it exceeds allowable limits. When that occurs, the car is flagged in a railroad’s computer system for replacement of the wheelset with the defective wheel. Similar processes occur for hotbox detection (thermal scanners, acoustic detection equipment). Another potential defect is an air brake test; every railcar must have a five-year brake test conducted, which is them reported in UMLER (Universal Mechanical Language and Equipment Register, a Railinc online tool for railcar data management). If a car exceeds five years without a brake test, it will be bad ordered to the railroad’s nearest shop track, and the brake test conducted. Similar to WILD detectors, truck hunting detectors can sense excessive lateral loads in the rails, an indicator that a truck on a railcar is “hunting”. That is, as the truck components wear, alignment between the bolster and sideframes weakens, allowing the wheels to oscillate from side to side instead of tracking a straight path. This condition is known cause derailments, particularly on long, light cars such as flatcars and gons. A truck hunting alert will usually trigger a trip to a repair track or home shop to tear down the truck(s) and replace any worn components (such as friction wedges).
Other defects are noted upon inspection. For example, when a train is assembled at a yard, a carman will observe a roll-by inspection, or drive the length of the train and look for defects. These can include things like: dragging equipment (air hoses), thin wheels, defective safety appliances (handrails), defective reflective striping, or loose or shifted loads. Still other defects are noticed by operating crews, such as: defective coupler cut levers, broken knuckles, or air brake problems (e.g. defective air brake valves).
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| UTCX 49270 and another loaded plastic pellet hopper sit on one of the RIP tracks at the west end of CN's yard in London, ON. Likely the result of a minor derailment, plastic pellets have flowed out of each car due to broken/cracked pneumatic discharge outlets on the gates, a common problem even in a minor derailment because they nozzles are so low to the rail. This repair would likely result in a trip to a home shop (once sent to customer and emptied), since railroads generally don't repair plastic pellet hopper gates. Storage of some spare wheelsets can be seen at lower left. |
Repairing Those Defects
After reading the above section, it may seem like there are a lot of things that can go wrong with a railcar; that is generally true, but a railcar is not likely to have multiple defects at the same time (though, for example, while brake testing a car, the carman might also notice other defects such as a cracked coupler body). Likewise, the frequency with which a car may require repairs (except perhaps, for brake shoes) is usually very low. Unless required due to collision or derailment, a car may run thousands of miles without any major repairs. But when a car does need to be repaired, where does it go? Generally, the nearest place capable of repairing it. Most larger yards on Class 1 railroads incorporate some form of a repair-in-place (RIP) track where minor/quick repairs can be made with minimal delay in transit, especially important for loaded cars. A typical RIP track will usually have somewhere that the car can be jacked up (to replace wheelsets or truck components), and may be located adjacent to a building used by carmen to store parts or for office space. Sometimes, a RIP track may have its’ own car mover (e.g. Trackmobile) to avoid tying up other yard engines. Some shortlines that do not have capacity to conduct repairs may have an arrangement in place for a nearby Class 1 to conduct repairs.
If a railroad determines that a repair is beyond the scope of what they can handle, such as derailment damage or specialized repairs on tank cars, hopper cars, or other specialty equipment, they can contact the car owner and request disposition to a home shop (operated by the car owner, such as a leasing company), or a third-party repair shop designated by the car owner (assuming car is safe to move on it’s own wheels). If a car is damaged heavily, either from a wreck, or through typical operation (such as a broken sill), and the car is not safe to move on own wheels, the railroad can settle with the car owner for depreciated value (I think I’ll do a future post on this, as this is a lot of what I worked on during my tenure at my summer employer).
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| At left, the RIP track at CP's Quebec Street yard in London is pretty full today. Looks like the carmen will have their work cut out for them! The building at centre is used to store MOW supplies and spare parts. Note the concrete pad for jacking a car just above the power line. |
Bad Order Cars and the Model Railroader
This is all interesting prototype information (to me, anyhow), but how does this relate to model railroad operations? Have you ever been switching in a yard and you can’t make a joint because one car has a broken coupler? (Recall those lousy plastic couplers Walthers used for years?!) While we may not be able to implement automated defect detection on a model railroad (but wouldn’t that be cool?) we can still interact with bad order cars. Similar to above, if you find a car with a missing coupler spring, bad order it to the RIP track. If you don’t have one on your layout or yard, perhaps park the car on a lightly used spur or siding where the carman can come on-site and repair it. Another common problem with model railcars is tight (or loose) trucks, leading to derailments or excessive (unprototypical) rocking and rolling while in motion. Dragging coupler trip pins are another reason your yard crew could send a car to the RIP track. There are many other reasons I’m sure, and these are just a few. An alternative that I have seen modeled is to randomly bad order a car during an operating session. This mainly applies to modern layouts where one has modeled a WILD or hotbox detector, but in theory, anyone can spot a wheelset with a thin rim or that is high impact (for steam-era modelers, repacking the journal waste would be a common bad order reason). For even more realism, Boulder Creek Engineering has developed an HO scale defect detector remarkably similar to prototype railroads’ defect detectors (http://www.bouldercreekengineering.com/trainboss.php) . One can program the automated voice messages, defect types (hotboxes, dragging equipment, etc), and defect probability. The system uses optical sensors to count axles and will playback other data as well (temperature, speed, etc). I think it’s a pretty neat way to add some realism, especially for your operating crew whose train gets caught by the detector with a defect!
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| Presently, I have two cars on the RIP track, which is adjacent to the yard (the diesel shop will be located on tracks at lower right). CMO 21277, an Athearn RTR Trinity 5161 CF hopper is bad ordered for a missing B-end hopper gate (fell off in box), while PROX 43931 needs a new A-end coupler spring, a common defect with the McHenry scale-head couplers. Once complete, a pad to jack cars and some spare parts will be added to the RIP track. |
A typical RIP track doesn’t need much to be set up as such. The primary consideration is a safe place to jack a car, such as a concrete pad or wooden planks to create a relatively flat surface. Likewise, crane(s), forklifts, and spare components such as wheelsets can also be placed near the RIP track for added realism. And if you have the space, one might place a carman’s office nearby, or have the carman work out of the yard office if a separate building isn’t possible.
I think that’s enough for now,
‘Til next time,
- Peter.
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