OK. But if you want my personal preference, when I write for an international audience, I try to reduce the number of extraneous words and use a "lighter" sentence structure.

laid or moved under low tension > subjected to axial tension

The axial torsion > Torsion > or ...
> Torsion about the cable's axis produces a twist that reduces tension in the armor. The reduced tension can allow the spiraled armor to expand like a bird cage, which can also result in a looped cable.




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Tks 1503-44

Welcome. Sometimes planting the basic idea firmly into your audience's head is better than writing your most accurate technical description. Anyway, either one is OK. At least you have a choice now and you are the only one that knows your audience, so select accordingly.

final text : -

Birdcage buckling Is a phenomenon which occurs in armoured subsea power cables and flexible’s when subject to low axial tension or twisting opposite to the direction of the cable lay up ie during manufacture, lay or loadout.
The axial torsion within the cable generated by both the twisted cores and/or the helically wound steel wire armor act to produces a rotational twist in the cable, this causes a reduction in tension of the armour wiring thus causing it expand and open like a bird cage, it is occasionally accompanied by a loop in the cable. A birdcage can seriously damage a cable requiring costly repair.

How about

"Armoured subsea cables need to be laid with large axial tension.

If this tension reduces or becomes zero, there is a phenomenon called "bird caging" which results is the armour delaminating and creating an expanded bundle of wires resembling a bird cage. This requires costly repair."

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Thanks Little inch, text submitted to client now