Cov lus piav qhia luv luv:

Cov Casing Rotator yog qhov tshiab tho kev sib koom ua ke nrog kev sib koom ua ke ntawm lub zog hydraulic tag nrho, thiab tswj kev sib xyaw, lub zog thiab kua. Nws yog ib qho tshiab, ib puag ncig thiab siv thev naus laus zis heev. Nyob rau hauv xyoo tsis ntev los no, nws yog dav saws hauv cov phiaj xwm xws li cov kev tsim kho ntawm cov khib nyiab hauv lub zos

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