[ List Subjects ][ Post Message ]
Subject: technical information about the aluminum alloy 6101-T4
[ View Followups ][ Post Followup ]
Date: 06/05/02 at 10:24 AM
Posted by: Paulo Americo de Mattos Cardoso
I'm studying the application of aluminum alloys in fittings commonly used in overhead transmission lines of the company in whicch I work.
Initially, I studied and applied a conductor cable that works in a range of maximum temperatures oscillating between 150°C ( without aging) and 180°C(with aging).
In that occasion, I proceeded the material employee's evaluation in their
fittings, even so now in a second work, I intend to go more thoroughly in the
For not disposing of bibliographical references on this subject, I am
counting with your collaboration so that I can solve and elucidate
with this some doubts.
I have the following comments / doubts to do:
1 - the commonly used alloy in the conductor cables of our overhead
transmission lines is 1350 EC (hard temper / duty ?).
2 - the manufacturers of fittings with aluminum alloys for the overhead
transmission lines, uses here in Brazil the aluminum alloy 1050 (rich in
aluminum, low quantities of silicon and magnesium) and 6101-T4 (less aluminum in
its chemical composition, even so more silicon and magnesium that the previous,
and the magnesium increases the mechanical resistance of this aluminum alloy in
relationship to the previous one).
3 - Other concept also obtained with the manufacturers is that the aluminum alloy
6101-T4, after its solution, and with the temperature increase and
aging, changes from T4 to T6.
4 - it is also used in Brazil, even so in small scale, the league 6201
as conductor cable. It has the characteristic of presenting smaller expansion linear coefficient, consequently smaller sag in the conductor cables.
5 - the Japanese conductor cables that I studied, is of the series of
aluminum alloys 8000, and above the Japanese aluminum alloy that is already
nationalized, there are other two alloys . The aluminum alloy ztal and xztal, whose conductor cables operate with the range of temperatures around 240°C and 330°C.
6 - the national conductor cable manufacturers , that the annealing occurs in a temperature around 93°C, while this fact doesn't occur with the aluminum alloys such as tal, ztal
and xztal, in function of the presence of the zirconium and lantânio in the alloy.
The overhead transmission line fittings manufacturers already inform that the
annnealing occurs in temperatures greater than 93°C. This is my doubt, that will be explained better with the explanation of the experience that is in process.
7 - In the experience that I meet accomplishing in laboratory of
fitting manufacturers, we are beginning, with the temperature of the control conductor cable around 180°C, two anchorage compression fittings , with different dimensions.
One of them, for having larger dimensions and more mass, for a same value of
current, presents inferior temperatures to 90°C. In my opinion on
the subject, this fitting won't present annealing problem with respect to the
aluminum, therefore it won't present reduction in supporting efforts
mechanics, when compared to the other fitting.
The other sample, presents smaller dimensions, and for the same value of
current mentioned above, presents superior temperatures to 90°C. Such
fact would occur in the annealing of the aluminum, with reduction of yours
Is my way correct of analyzing the situation with regard to the annealing of the aluminum alloy?
Face to the facts exposed above, I'm needing a help to my technicians questions, as well as bibliographical references to clarify them.
Expecting your answer, as sooner as possible, I'm grateful in advance,
Paulo Americo de Mattos Cardoso
Post a Follow-up: