I’ve seen tamping machines and other track maintenance equipment inch their way along the track as they re-set the ballast etc, etc - [wow] fascinating! - but how do they handle more complicated configurations of track, e.g. switches, crossovers? Do track maintenance machines have a special adjustment capability, or is it handled another way? [%-)]
Dave [:)]
Most on track machines traverse the rails the same way as other railroad equipment. Some equipment such as tampers and ballast regulators has internal turntables to allow them to turn around, but that has no effect on switches or crossovers…
LC
Thanks LC - I guess I was more after how these machines actually re-set the ballast etc underneath switches and crossovers…I think my question could have been worded better. [
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Dave
When Mudchicken comes in out of the cold again, he’ll probably be able to bring us up to date.
But when tamping machines first came around, they were only good for handling track without switches or special trackwork. Those still had to be tamped manually. But I’m pretty sure that some companies have come out with machines that can tamp and surface switches (perhaps exclusively, as they might not be fast enough to use on “normal” track), and perhaps a true all-track tamper has been invented. If not, it’s probably only a matter of time.
Carl - Your comments are appreciated - I agree, Mudchicken will have the good oil on this, or someone else similarly experienced…
Dave
Dave -
Sorry, I misunderstood your question. As I understand it from talking to track folks there are many combination machines out there that can do some or all of the trackwork that formerly was done by single machines. As to tampers I know there are production tampers which are primarily used on tangent (straight) track and there are switch tampers which can handle all manner of switches and other specialized trackwork and that they are equipped with jacks to enable such work in addition to the normal tamping “picks” that perform the actual tamping. Hope that helps.
LC
Kozzie:
On most modern production tampers (Harsco Tamper/ Harsco Jackson/ Plasser), the workheads (Tamping tools, vibratory motors & squeezing action all in one assembly) can travel sideways on folding trolleys (small I-Beams)on the machine.
The regular rail clamps that grab the rail and pull -up are supplemented by extra clamps that can reach out and pull-up to handle the extra long switch ties. (a man with a track jack is still needed sometimes to help level the switch panel with all those varied long ties supporting the turnout)
These machines are getting so big that self contained turntables (rotary jack stands) can no longer be used. (the machines are too heavy and unbalanced/unsteady to try that anymore)
Ballast Regulators can handle everything but the switch points (h*ll on broom rubber and jams rocks in the part of the switch that moves, requires lotsa handwork to clean up)
Answer your question?
Frosted Trampled Feathers[banghead][banghead][banghead]
PS - Your red and yellow Aussie EMD is still in Pueblo running in circles
Mudchicken - thanks for your reply [:D] - that sure does answer my question - we knew that you’d know! [swg] Thanks again!
Dave
New 3 point tamping and linning machines (plasser etc) use a Windows based computer system called ALC. This system basicly does away with manual tamping. The machine operator wil be given one of 4 pieces of information before he starts. namely, minimum lift, max lift, linespeed and datum rail. One of the most important is what rail will be used as the datum rail, ie, the rail wich requires the least amount of lift. (if the wrong rail is chosen, more ballast is used than nes and can result in you running out of ballast!) The machine then does a measuring run and depending on line speed, lenght of transitions, cant and lift will generate a design for the line to be tamped. All the operator has to do is go exactly to where he started the measuring run and lower and raise the tines to start the tamp. Sqeeze and tine depth are all handled by ALC depending on the type of track being tamped, ie, normal or shallow depth sleepers.
When tamping turnouts and crossovers most of the above is true except that the datum rail will be a rail with a continuous run, ie, hopefully one rail with no crossing in it (frog). This is carried out by a switch and crossing tamper. These machines as rightfully stated above, can pick up a rail with the clamps a fair distance from the machine when tamping long ties. But for a good job this should stll be supplemented with manual jacking. These machines can also ‘flip up’ tines out of the way to avoid hitting other rails and all the other obstructions in turnouts.
The track was redone last summer at the Golden Spike NHS and the contractor used smaller, older machines as they must be trucked in. IIRC the tamping machines worked most areas of the switches quite well - but each switch also took a lot of hand adjustment. Two of our switches are stub switches - with no continous rail and they are tricky to keep aligned. One switch actually is almost too tight for the engine and they were able to manually adjust that switch and really improve operations. The difference before and after their work was significantly improved. However, one switch developed a sag later in the summer after the contractor left that will require jacks and manual tamping to fix next spring.
dd
Thanks everyone for your comments - sure does answer the question. Interesting to see how improvements in technology can be applied to railways.
Dave