Actually, Paul, that is exactly what happens. BUT ONLY IF THE COUNTRY OF
ORIGIN REQUIRES IT!
I hate to shout, but this can't be stressed too much. I also don't like
singling out a particular country, but some countries do not require
the same testing that other countries do. I am trying hard to be vague
and specific at the same time here. I am also giving some guidelines on
how to deal with contingencies without facing the threat I face every
day of being sued for failure to inform correctly...
Chain is fine for heavy lifting. THE CORRECT CHAIN IS EQUAL TO THE
CORRECT LOAD. As an end user it is your responsibility to make sure you
are using the product within that product's limits. The average home
user is not qualified to know when a piece of rope or webbing has enough
broken strands to disqualify it for use. On top of that there's the
question of knots. There are few knots that come close to 75% of the
strength of the rope. Are you going to advise people to use rope with no
knowledge of how to tie it? You do know that by putting a knot in rope
you can degrade the lifting capacity of that rope by 50% don't you?
I'm not an elevator engineer (though I've built a few orchestra pit
lifts). I'm a theatrical engineer. My guess is that they use wire rope
because it's MUCH quieter than chain. (Quiet equals confidence. Any
elevator engineers out there?). I can only vouch for my own area of
expertise. Whenever a piece of rigging gear is sent up to hang in the
air on a theatrical or concert event, every inch of the equipment is
inspected before it goes up and subject to rejection if a single strand
of wire rope is broken or a shackle doesn't work like it's supposed to.
Back to the original discussion, chain is the stuff for lifting engines,
DEPENDING ON YOUR SITUATION, but you need to make sure you have the
chain equal to the job and all the other parts of the system are
sufficient. Our original poster obviously didn't have the right stuff. I
have full confidence he will next time around.
> From: "Paul Hunt" <paul.hunt1@blueyonder.co.uk>
> Subject: Re: [Mgs] watch your chains
> To: "MG Mailing List" <mgs@autox.team.net>
> Message-ID: <914FAC8DBC5041179D3765F718EEE5A7@paul>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> Surely this type of chain is *not* suitable for lifting? From the name
> 'proof coil' I imagined samples had been tested by a proof test house and
> warranted to carry a certain load.
--
Nil desperandum
Glenn Schnittke
-----------------------
g.schnittke@comcast.net
Home - 615-837-5883
Cell - 615-319-5534
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