Gearboxes shall be taken as the standard unit. To adjust bottom base by referring to horizontal subdivision section of gear box, box body processing datum plane or support of bottom base;

compressors 齿轮箱为基准机，进行底座调整时以齿轮箱水平剖分面、箱体机加工基准面或 底座支承为基准，同时兼顾压缩机和电动机侧水平仪。

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The desiring installation method of installing insert ball bearing unit is: first install the housing at support base firmly, then tighten the bearing to the shaft.

安装带座外球面球轴承时，将轴承套在轴上，先将轴承座牢固地固定在支承面上，然后将轴承紧固在轴上即可。

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There will likely be a significant drop-off in demand for the munitions that the unit supplies to the Army and Marine Corps, but GD has built up a strong base of support in Congress for protecting its core vehicle franchises.

FORBES: General Dynamics Begins 2013 With New Leader, Changing Business Mix