All wrote:
>> Is the load on the brake winch less now that I have four pulleys instead of
>> two in the
>> cabling system so that it won't heat up as much?
This is a bit of a trick question, isn't it?
Sure the pulling force, at any time, is less on the brake winch. That's
why it's easier to turn it.
But you also talked about braking and heat dissipation.
There is potential energy when the tower is vertical. Lowering to
horizontal, makes a bunch of potential energy go somewhere.
Assuming the tower touches the ground with no impact force (no ground
deformation)... all the energy must be dissipated by friction in the
system (pulleys, pivot bolts, plus the winch) while lowering. (assuming
your muscles don't provide any braking force)
So: arguably, the total amount of heat the brake sees, is roughly the
same. It's just seeing it over the time for twice as much wire travel.
If you run the wire at the same speed as before, it takes twice as long,
so the energy is dissipated over twice the time period. This may be
sufficient for normal heat dissipation in the winch.
If you're running the wire twice as fast as you did before, then maybe
the heating issue hasn't changed (although you have some extra friction
elsewhere now in the system).
I guess the answer is: just because it's easier, don't run the cable faster.
at least. that's my thoughts.
-kevin
ke6rad
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