Shed and Yard Shunting.

The efficiency of goods shed operation largely hinges on the facilities provided outside. It is necessary therefore that the track layout should be designed to facilitate rapid handling and that the motive power to move the wagons should always be ready to hand when required.

In this country, as most of my readers know, shed and yard shunting is done by a yard engine, in some cases supplemented by horses. Each morning wagons are placed in the sheds and yards for loading and unloading and draws made when all wagons are ready, or when it is most convenient, that is to say, during meal hours, or when an engine is available.

In large centres the use of the yard engine for dealing with shed traffic is apt to become uneconomical, especially at busy periods, in that groups of men have to stand idle until an engine is free to draw the loads.

There are many devices for relieving shunting engines of this work. Illustration 1 shows one of the methods of handling shed wagons in Britain. Electric capstans pull the wagons in and out of the sheds and by means of turntables switch them to and from other roads. The turntable method was introduced in congested areas where adequate track facilities could not be provided. It considerably reduces shunting and sorting at the end of the day. Further, with a grid-iron layout, wagons can be moved from the goods sheds to the goods yard and vice versa without utilising engine power and without interfering with ordinary station yard work. The great disadvantage of this system is, however, that only four wheeled vehicles can be handled, and it is not recommended for a country where high capacity wagons will possibly become the standard.

Where space is available the better method is to provide sufficient tracks outside the sheds to enable capstans to feed and clear the sheds as required. The shunting engines can then handle the wagons when time permits. Diagram 3 shows three sample layouts and the position of the capstans and dummies.

A single road shed equipped with a capstan requires two roads outside, each of the same capacity as the shed road. The shed road is filled in the morning and one of the two outside roads is utilised for surplus wagons arriving during the day. When the shed is required to be “drawn” the capstan hauls the wagons on to the empty road and refills the shed from the other.

For sheds with two roads it is usually found that three outside roads accessible to both shed roads are sufficient, unless the peculiarities of the traffic require the drawing of both roads at the same time. In such cases accommodation of twice the capacity of the two shed roads would be required. This can be found either by providing four roads equal in length to the shed roads or three roads sufficiently long to accommodate twice the capacity of the shed roads. The layout in every case depends upon which direction ground space is available.

The modern capstan can haul up to 100 wagons at a time and an operation is simple and safe. As will be noticed in the illustration the capstan man takes two turns of the rope, his foot is on a push button operating the motor. By rotating the drum and applying slight pressure by gripping the rope the drive is taken up. At instant notice he can release the pull on the rope by slackening his grip. For the benefit of my readers who may be called upon to use a capstan I would like to add a word of warning. Never take more than two page 25 turns of the rope round the capstan and always coil the loose rope as seen in illustration. For safety a hemp rope should invariably be used.

In addition to the capstans there are other methods of moving wagons by mechanical means, such as tractors, ordinary motor lorries, etc. Lately a new type has been tried whereby a kind of wheelbarrow operated by an electric battery pushes or pulls the wagons. The various efforts in this direction indicate that there is a field for a more economic method of making small shunts in yards than by the ordinary shunting engine.

It should not be thought that all sheds must be equipped with mechanical appliances for shunting. Before any decision is made regard must be had to the general organisation of the shunting services of the station yard, i.e. the number of engines employed, the position of the sheds in relation to the station yard, the number of goods yard roads and shed roads to be drawn at the same time, general track facilities, etc.

The timetable also enters into the question. Possibly the hour the shunting engines are fully occupied getting trains away, conflicts with the most convenient time for shunting the sheds. Again, incoming trains may arrive at an inopportune moment and interfere with the drawing of sheds.

It can be seen therefore that each case has to be fully investigated, bearing in mind not only the £s.d. aspect of the case, which is sometimes difficult to determine, but that efficiency in the operation of a yard has very far-reaching effects. This applies particularly to single line operation. A quarter of an hour's delay in one yard can soon spread disorganisation in all directions. Main line trains are delayed and terminals and sub-terminals 200 and 300 miles distant are affected. I mention this, because, from my own experience, I have noticed very often schemes have been turned down because operating officers have not been able to determine the exact monetary saving, whereas, they know, from practical experience, the capital outlay would be amply justified.