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#91303 - 01/09/05 07:00 AM torque
kd Offline
Member

Registered: 12/14/04
Posts: 51
When I torque lugs using Aluminum wire, I will apply, say 50 ft. lbs., then several days later check the torque. It will be down to, say, 35 lbs, so I re-torque it. Other ECs say you should just torque it and forget it--that the loss in tightness is built-in to the required torque. Of course Copper holds its torque so it is not a problem. What do you guys and gals say about this?

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#91304 - 01/09/05 07:47 AM Re: torque
Tom Offline
Member

Registered: 01/01/01
Posts: 1069
Loc: Shinnston, WV USA
Torque it once to the specifications for the lug & leave it alone.
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Few things are harder to put up with than the annoyance of a good example.

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#91305 - 01/09/05 08:37 AM Re: torque
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
How does an inspector know how much you've torqued a connection? I am a fan of the break away connection.
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#91306 - 01/09/05 09:38 PM Re: torque
Physis Offline
Member

Registered: 12/28/04
Posts: 85
Loc: Burlingame, Ca. USA
Another reason to not like aluminum as a conductor.
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#91307 - 01/10/05 04:13 PM Re: torque
John Steinke Offline
Member

Registered: 04/03/01
Posts: 509
Loc: Reno,Nv., USA
Not "another" reason- THE reason! Aluminum is notorious for "creep" when over-torqued. Aluminum should not be torqued to the same values as copper for this reason.
Simply put, too much pressure causes the metal to flow, leaving you with a loose connection. Make sure the value you're using is the correct on, and not "something always used."

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#91308 - 01/11/05 09:31 PM Re: torque
kd Offline
Member

Registered: 12/14/04
Posts: 51
Aluminum association torque table shows the sasme values for Cooper and Aluminum.

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#91309 - 01/17/05 05:24 PM Re: torque
Nick Offline
Member

Registered: 08/13/01
Posts: 603
Loc: Riverside, CA

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#91310 - 01/18/05 08:21 AM Re: torque
resqcapt19 Offline
Member

Registered: 11/10/00
Posts: 2209
Loc: IL
The following is a very important quote from the document that Nick has posted a link to.
 Quote:
It is often asked whether bolted connections require periodic retightening. The simple answer is NO. Once the connector is installed with the proper torque, repeated tightening could actually damage the connector and/or the conductor and eventually lead to a failure.

Don
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