On May 12, 2004, at 11:45 PM, Steven W. Reilly wrote:
>
> Looking at buying a winch........just not sure about one thing.
>
> Lets say that a winch is rated at "9000lbs single line pull".
>
> Does this mean that the winch (if so used) would be directly capable
> of lifting 4.5 tons?
>
Yes. Some caveats, though. First, winches are not rated for overhead
lifting. So you don't want to do that, generally.
Second, the rated pull is only available on the first wrap of cable
around the drum. On the subsequent wraps, pulling power is markedly
reduced. So if you've got 100' of cable on it, and only pull out 10,
you'll only have 2/3 or so of the rated power. (Good winches provide
the numbers as part of the specs.) This can be a real bummer. For
self-recovery, you generally want as long a cable as possible, as
whatever you want to attach to is always 3 feet farther away than your
cable can reach. Except when you're really, really stuck, and the
anchor is 15 feet away, and you can't pull yourself out without needing
a snatch block or three. So, if you're buying a winch for
self-recovery, or other off-road use, big long cables are good. If, on
the other hand, your putting a winch on tailer to haul cars on and off,
or launch boats or something like that, then you need to consider how
long a pull you're going to do, and how close the load you're puling is
to the rating of the winch. If you look at most flatbed tow trucks,
they've only got about 50 feet of cable on their winches, even if the
drum will hold 150'. It's really, really embarrassing not to be able
to get a car on the deck. Pulling a smashed one-ton truck onto the
deck might well take close to the rated pull of winch, and a full drum
wouldn't manage. Since they're not usually used for serious "wow, how
did you get a car *there*?!" recoveries, that's okay. An extension
wire rope can be used if you need a longer pull on occasion, though
that does mean the load has to be re-rigged mid-pull.
Third, ratings lie, and duty cycles suck on most electric winches.
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