Cov kev phom sij zais cia tau muab faib ua 21 pawg: Hluav taws kub, tawg, lom thiab ua tsis taus pa, dej puas, tawg, av sib tsoo, to, corrosion, hluav taws xob poob siab, poob, mechanical puas, thee thiab gas outburst, txoj kev puas tsuaj, tsheb puas. , railway chaw puas tsuaj, ...
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