Hydraulic nangula pobowola rig ndi makina okhudza pneumatic, omwe amagwiritsidwa ntchito makamaka ngati nangula wa miyala ndi dothi, subgrade, chithandizo chotsetsereka, kuthandizira dzenje lakuya pansi, ngalande yozungulira kukhazikika kwa miyala, kupewa kugumuka ...
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