Welded semi-rigid centralizers maturusi akakosha muindastiri yepetroleum, uye mhando yechigadzirwa yakakosha kuve nechokwadi chekubudirira kwekuchera uye kuisa simende mabasa. Sechivanhu, centralizers inogadzirwa nesimbi yepamusoro, iyo inodhura. Nekudaro, kuburikidza neuniq ...
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