South Devon Railway - Railway Wheel Construction

The
South Devon Railway
'Railway Wheels'

Ever wondered why the flanged edge of a railway wheel is called a tyre ?
Well the wearing surface is a separate entity which has good wear properties and, to keep the costs down, is replaceable.
The tyre is heated to expand it and then the wheel is lowered into it. Whilst still hot a circlip, called a "Gibson ring" is sprung into the recess in the back of the tyre. To hold this in place the back of the tyre is rolled down to crimp the tyre in place.
The sectioned wheel below illustrates the component parts.
Carriages and wagons use external axle boxes on the ends of the axle shaft whereas most locomotive journals are inside the wheels because of the connecting rods.
Details of the Gibson ring press are below along with pictures of the tyre heating ring from the former GWR workshops in Swindon.

A section through an assembled railway wheel

The component parts of a railway wheel

In the photograph above you'll notice the edge of the tyre is bent over onto the Gibson ring. This is done using a special press as in the next photographs.

Wheelset mounted in the Gibson Ring press (note rollers adjust to compensate for wheel diameter)

Close up of the rolling action


Outer pipe and burners are from Swindon. Hoses are new with self sealing connectors.	Photo ^© Gavin Bishop 2006

Detail of individual burners (number of burners is adjusted to match diameter of tyre.	Photo ^© Gavin Bishop 2006

Over the first weekend in August 2007 the first of six tyres was machined and fitted to one of 3205's wheelsets. Here are a sequence of photographs shewing the process.