【判断题】
机组运行中,当循环泵突然掉闸后,凝汽器水侧中的水不流动,对保护凝汽器铜管最有利
A. 对
B. 错
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答案
A
解析
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循环水允许的浓缩倍率越大节水效果越明显
A. 对
B. 错
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循环水管道由于工作温度低,其热伸长值较小,依靠管道本身的弹性压缩即可作为热伸长的补偿
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汽轮机停机后真空到零,如果凝结器水位不高可以马上停止循环水泵运行
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抽气器的任务是将漏入凝汽器内的空气和蒸汽中所含的不凝结气体连续抽出,保持凝汽器在高度真空下运行
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凝汽器的作用是建立并保持真空
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凝汽器端差是指汽轮机排汽压力下的饱和温度与循环冷却水出口温度之差
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【判断题】
凝汽器在正常运行中有除氧作用,从而提高凝结水质量
A. 对
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【判断题】
汽机排汽在凝结器内凝结过程可以近似看作变压、变温凝结放热过程
A. 对
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【判断题】
汽轮机的排汽在凝结器中凝结成水,只放出汽化潜热,但温度不变
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【判断题】
汽轮机热态启动时凝汽器真空适当保持低一些
A. 对
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汽轮机运行中,凝汽器入口循环水水压升高,则凝汽器真空升高
A. 对
B. 错
【判断题】
汽轮机运行中当凝汽器管板脏污时,真空下降,排汽温度升高,循环水出入口温差减小
A. 对
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【判断题】
提高凝汽器真空,可提高机组运行经济性, 但是,凝汽器的真空不是提高得越多越好
A. 对
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【判断题】
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A. 对
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【判断题】
运行中凝汽器进行半边隔离时,应先隔离水侧,然后关闭空气门
A. 对
B. 错
【判断题】
凝汽器的端差是指凝汽器排汽温度与凝汽器循环水进口温度之差
A. 对
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【判断题】
凝汽系统的投用工作应在锅炉点火后完成
A. 对
B. 错
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凝汽器的空气冷却区可以减轻抽气器的负担,改善抽汽效果
A. 对
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【判断题】
凝汽器运行中,当不锈钢管结垢时,将导致循环水传热下降
A. 对
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【判断题】
汽轮机正常运行中凝汽器的真空不是靠真空泵来建立的
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凝汽器水位过高的明显标志是水位显示高凝结水过冷度大
A. 对
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【判断题】
凝汽设备主要由凝汽器、凝结水泵、抽气器等组成
A. 对
B. 错
【判断题】
凡是经过净化处理的水都可以作为电厂的补给水
A. 对
B. 错
【判断题】
凝结水泵安装在热水井下面0.5~0.8m处的目的是防止水泵汽化
A. 对
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【判断题】
提高蒸汽品质应从提高凝结水、补给水的品质着手
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【判断题】
为保证凝结水泵在高度真空下工作,需用生水密封盘根
A. 对
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【判断题】
一般每台汽轮机均配有两台凝结水泵,每台凝结水泵的出力都必须大于或等于凝汽器最大负荷时的凝结水量
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备用凝结水泵的出口电动门应处于关闭状态
A. 对
B. 错
【判断题】
凝结水的精处理设备严禁退出运行,在凝结器铜管发生泄漏凝结水品质超标时,应及时查找、堵漏
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A. 对
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