Re: trams riding on flanges

[geoff Oliver <ggo@alphalink.com.au>]

I once had to design a flangeway grinder  that would allow the ramps in the
flangeways  to be ground smooth after being rebuilt by welding.
I was told at the time that because of the sharper angles at crossings of
tramway turnouts ( and at 90 degree crossings) the ramp was needed to stop
tram wheels hammering the rails at the gap. Constant hammering of the rail
head will eventually cause a fracture.
I may be wrong, but I think that trains crossing the tramway at Glenhuntly
also ride on their flanges through the crossing work.
Also at Spotswood there is a transition point were the broad gauge leaves
dual gauge track and trains ride on their flanges at the point where there
would normally be a point blade on a turnout.

Chris wrote:

> I was wondering if the practice of Melbourne trams bearing the full
> weight of the tram on it flanges as it goes across crossings and points
> is safe?
>
> It seams to me, as I drive my trams along (I work for Swanston trams),
> say St Kilda Rd that all the crossings have been built up so that the
> tread of the wheel does not touch the track. In fact if you look at the
> rails at certain places they are in fact rusty, despite beign heavily
> used.
>
> I can only guess this is being done to avoid wear on the rails. But I
> was wondering if the trams them selves were designed so that the flange
> can bear the full weight of the tram or is this a cheap way of getting
> around the fact that the rail compnents should be strong enough to
> sustain heavy traffic with out wearing out so quickly.
>
> CNS