Nyob rau hauv cov xwm txheej tshwj xeeb, lub cev muaj zog xav tau cov qauv tsim tshwj xeeb, uas yog qhov ua tau zoo ntawm cov qauv tsim, feem ntau yog raws li cov qauv tsim qauv ntawm lub cev muaj zog, kom lub cev muaj zog muaj peev xwm tiv thaiv tshwj xeeb (xws li tawg-pov thawj, tshuaj lom neeg. anti-corrosion, sab nraum zoov ...
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