Friday, 3 September 2010


In a previous life I spent many an hour laying railway track by hand. There is an old saying: "the lightest thing on the railway is the pay packet." Believe me when I say that this saying is true, especially as I was working as a volunteer.

Say you have a perfectly flat area of land that has already been improved with adequate drainage and a good bed of ballast. First you have to lay sleepers (timber or concrete) at the right spacings, then attach chairs, lift the rails into the chairs, key the rails into the chairs and then attach the rails together with fishplates (*). That gives you a basic track layout. It then has to be aligned perfectly according to the plans, and then ballasted and packed (the ballast forced between and underneath the sleepers) by hand.

Add in other tasks, such as cutting the rails to length, greasing the joints, and adding shims, then you have a job that is both lengthy and time-consuming. This is a worst-case example for cash-strapped oganisations who use second-hand materials; machines can do some of the work (such as packing the track), and brand-new materials can make the entire process less bothersome.

This is what makes this video so fascinating (also see here and here). It is a train that literally lays its own track, then pulls itself along the track to lay the next stretch. This takes place in a continuous, seamless operation. Of course this only lays the basic track that can be run along at minimal speed. It then needs to be ballasted, and there are other machines that both lay the ballast and pack the ballast between the sleepers.

I look at the ease with which the machine lays the track and cry. For an example of the manual way of doing things, see here (and they are cheating by using a pneumatic hammer to help with the packing). For the mechanised version of this, see a ballast tamper in action, along with a far smaller version. If you have ever tried packing ballast with a shovel, then you will know how much effort this saves. The machines may be expensive, but so is manpower.

I love automation.

(*) This is for bullhead track; there are many other combinations of rail and sleeper, for instance flat-bottomed continuously-welded rail on steel sleepers.

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