Nakuba iziphethu ze-torsion ezishisa uwoyela zishisiswa futhi zicinywe ngamafutha, iziphethu ezifakwe i-zinc-galvanized zingaphansi kwenqubo yokufaka i-hot-dip galvanization.Le nqubo ihilela ukucwiliswa kwesiphethu sensimbi etsheni ye-zinc encibilikisiwe emazingeni okushisa aphakeme kakhulu.
Abantu abaningi bakhetha iziphethu ze-torsion enazinki ngenxa yokumelana kwazo okumangalisayo nokugqwala nokugqwala, sibonga kakhulu ngenqubo yokufaka imfucumfucu yediphu elishisayo.Ngaphandle kosongo oluqhubekayo lokwakheka kokugqwala, iziphethu ezinamanzi zinc zinikeza impilo ende kunemithombo eminingi efutheke uwoyela.