油泵主动齿轮油封损坏，空气进入液压系统；

The oil pump drive gear oil seal is damaged, the air into the hydraulic system;

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齿轮油泵在运转时主动齿轮带动被动齿轮旋转，当齿轮从啮合到脱开时在吸入侧(A)就形成局部真空，液体被吸入。

Gear pumps in operation when the passive gear driven rotary gear, when the gear was torn off from the mesh to the side when inhaled (a) on the formation of partial vacuum, the liquid to be inhaled.

youdao

齿轮油泵在运转时主动齿轮带动被动齿轮旋转，当齿轮从啮合到脱开时在吸入侧(A)就形成局部真空，液体被吸入。

Gear pumps in operation when the passive gear driven rotary gear, when the gear was torn off from the mesh to the side when inhaled (a) on the formation of partial vacuum, the liquid to be inhaled.

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