Australian Axle loads

[mauried@tpg.com.au (Maurie Daly)]

Reading thru the Draft Standard documents for the so called National
Rail Network as published by the AROU we seem to have a recommendation
for loco axle loads of maximum 22 tonnes ( locos fully fuelled and
sanded) , but maximum wagon axle loads of 25 tonnes are permitted.
Does anyone know why this is , ie why are locos less.

Also, is there any real engineering reasons for the 22 tonnes.
When the Pilbara Iron Ore railways were built back in 1968,even then
they were running 32 tonne axle load locos on 60 kg/m rail.
There is today quite a bit of 60 kg/m rail on the National Rail
Network but we are still stuck with this absurdly low axle limit.
Irs even more absurd when you try to run 4000 HP locos on 22 tonnes.,


MD