注册化工2012专业知识下的几题答案? 21. 关于管路系统局部阻力损失,下列说法中正确的是 A 串联 管道系统,各支路局部损失一定相等 B 串联管道系统,各支路局部损失不一定相等 C 并联管道系统,各支路局部损失一定相等 D 并联管道系统,各支路局部损失不一定相等 我认为选D。只有并联管路才有支路的说法,所以A,B错;并联管路各个支路的总阻力相等,但局部阻力不一定相等。 54. 关于管道设计压力和设计温度选取,正确的是 A 已知泵出口正常压力为4.5MPa,泵出口最大关闭压力为5.7Mpa,泵出口 安全阀 开启压力5.0MPa,选择泵出口设计压力5.7MPa B 真空泵 吸入口管道设计压力取常压+吸入口液位差 C 当流体正常温度为310℃,选用管道设计温度320℃ D 当流体最低温度为-70℃,选用管道设计温度-70℃ 我认为选A,D。B应该是全真空;C应该是310+(15~30)=325~340。 希望各位大神给我合理的解释 查看更多0个回答 . 1人已关注
客户提供的关于阀门安装的说明,求大虾帮忙翻译解释一下 ...? 客户提供的关于阀门安装的说明,求大虾帮忙翻译解释一下,谢谢 Installation Don`t use flange sealings. The seat ring of the Butterfly valves has a sealing lip which operates as flange gasket between valve and flange during mounting. • Insert the valve with the disc in the nearly closed position between the flanges. lf the flanges are located too closely in an existing pipe, they must be so spreaded by means of a special device that the valve can be easily installed with clearance . • Mount the flange boIts and centre and align the valve between the flanges. Hand-screw the flange bolts. Spot weld the flanges to the pipe . • Before cross-tightening the flange bolts uniformly, it must be ensured by the test actuation that the valve disc can move freely within the connecting flanges . Attention! In case of improper insertion of the disc between the flanges, the seat ring may be displaced and destroyed during the first operations. Similarly, the sealing strip of the valve disc can be damaged if it is not observed that the disc can move freely between the flanges.查看更多4个回答 . 2人已关注