【单选题】
为提高加工中心静动刚度，基础大件通常采用 结构 ___
A. 封闭箱式
B. 加强筋
C. 倾斜
D. 大板
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答案
A
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相关试题
【单选题】
C.零件的尺寸 D.刀具磨损尺寸 13066.在下列几种平面度误差的评定方法中，只有 符合平面度误差的定义，其余均是近似的评定方法 ___
A. 最小区域法：包容实际表面距离为最小的两平行平面间的距离作为平面度误差值
B. 最大直线度法：以被测平面上各测量截面内的最大直线度误差作为平面度误差值
C. 三点法：以被测平面上相隔最远的三个点组成的理想平面作为评定误差的基准面，来计算平面度误差
D. 对角线法：以通过被测平面上的一条对角线且与另一条对角线平行的理想平面为评定基准来计算平面度误差
【单选题】
某加工中心进行镗孔时，所镗出的孔与其基准的相互位置度有误差，但未产生孔的形状误差，造成这种误差的原因可能是 ___
A. 机床导轨的导向误差
B. 机床传动误差
C. 机床主轴的纯径向跳动
D. 机床主轴的纯轴向跳动
【单选题】
C.输入端、输出端都在左 D.输入端、输出端都在右 13087.在分析进给伺服系统爬行故障产生的原因时，下列说法不正确的是 ___
A. 伺服电机不转
B. 接线端子接触不良
C. 负载大
D. 导轨润滑不良
【单选题】
数控机床运行过程中出现液压油液位过低报警，但检查油箱液位正常，最有可能的原因是 ___
A. 检测液位的传感器故障或线路断开
B. 油液严重泄漏
C. 油液太脏
D. 滤油器堵塞
【单选题】
在数控程序中，G00 指令命令刀具快速到位，但是在应用时 ___
A. 必须有地址指令
B. 不需要地址指令
C. 地址指令可有可无
D. 视程序情况而定 13093.机床加工时，如进行圆弧插补，规定的加工平面默认为 (A)A.G17 B.G18
【单选题】
C.工件坐标系 D.变更刀具补偿量方式 13096.常用数控系统一般通过地址 S 和其后面的数字来控制机床 的速度 ___
A. 主轴
B. 程序运行
C. 进给轴
D. 刀库回转
【单选题】
单活塞杆液压缸的有杆腔和无杆腔的有效工作面积不等，当压力油以相同的压力和流量分别进入缸的两腔时，活塞在两个方向的速度和 不相等 ___
A. 推力
B. 扭力
C. 扭矩
D. 转矩
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