trams riding on flanges

[Chris <csinn@netlink.com.au>]

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