The intermediate bearings are supposed to be steading bearings.
Some bearings have a coller that will lock the shaft to the race to
absorb a percentage of the load as thrust.
The coller you show does not look like that type of coller to me.
If it is running steel to steel as you think and producing the amount
of heat you indicate I think it is set up wrong.
Also heat is in this case wasted horsepower,you could use a smaller