相关试题
【单选题】
国产300、600MW汽轮机参加负荷调节时,机组的热耗表现为___。
A. 纯变压运行比定压运行节流调节高;
B. 三阀全开复合变压运行比纯变压运行高;
C. 定压运行喷嘴调节比定压运行节流调节低;
D. 变压运行最低。
【单选题】
汽轮机变工况运行时,蒸汽温度变化率愈( ),转子的寿命消耗愈___。
A. 大、大;
B. 大、小;
C. 小、大;
D. 寿命损耗与温度变化没有关系。
【单选题】
作真空系统严密性试验时,如果凝汽器真空下降过快或凝汽器真空值低于___MPa,应立即开启抽气器空气泵,停止试验。
A. 0.09;
B. 0.087;
C. 0.084;
D. 0.081。
【单选题】
数字式电液控制系统用作协调控制系统中的___部分。
A. 汽轮机执行器;
B. 锅炉执行器;
C. 发电机执行器;
D. 协调指示执行器。
【单选题】
根据环境保护的有关规定,机房噪声一般不超过___dB。
A. 80~85;
B. 85~90;
C. 90~95;
D. 95~100。
【单选题】
为了防止油系统失火,油系统管道、阀门、接头、法兰等附件承压等级应按耐压试验压力选用,一般为工作压力的___倍。
A. 1.5;
B. 1.8;
C. 2;
D. 2.2。
【单选题】
中间再热机组应该___进行一次高压主汽门、中压主汽门(中压联合汽门)关闭试验。
A. 隔天;
B. 每周;
C. 隔10天;
D. 每两周。
【单选题】
机组启动前,发现任何一台油泵或其自启动装置有故障时,应该___。
A. 边启动边抢修;
B. 切换备用油泵;
C. 报告上级;
D. 禁止启动。
【多选题】
运行中通过监视调节级压力的变化可以判断___
A. 新蒸汽流量的变化,负荷的高低;
B. 通流部分是否存在结垢、损坏及堵塞
C. 汽轮机叶片是否损坏、变形;
D. 主蒸汽压力的变化;
【多选题】
汽轮机通流部分结垢后,可导致___
A. 汽轮机接带负荷的能力下降;
B. 汽轮机的效率降低;
C. 汽轮机级的反动度发生变化;
D. 汽轮机的轴向推力增加;
【多选题】
汽轮机发生过大的振动时存在哪些危害___
A. 损坏机组零件;
B. 动静部分发生摩擦;
C. 造成基础松动或周围建筑物损坏;
D. 造成汽缸变形;
【多选题】
汽轮机运行中发生振动,可能的原因有___
A. 主汽温度过低或轴封带水发生水冲击;
B. 汽缸变形、滑销系统卡涩导致动静部分摩擦;
C. 汽轮机组转子弯曲、中心不正或叶片脱落;
D. 油质恶化有杂物、油压过低或油温过高;
【多选题】
运行中给水温度下降的原因有___
A. 高加换热管结垢、堵管较多或机组负荷下降;
B. 高加换热管发生泄漏;
C. 高加液位过高或水侧流量突然增加;
D. 高加内部隔板泄漏或水侧旁路未关严;
【多选题】
由工业冷却水供给密封水或冷却水的设备有___
A. 给水泵、凝结泵、真空泵冷却水;
B. 润滑油冷油器、EH油冷油器和发电机空冷器;
C. 给水泵、凝结泵密封水;
D. 润滑油油净化装置真空泵;
【多选题】
向辅汽母管供汽的汽源有___
A. 两台机的三段抽汽;
B. 两台辅汽减温减压器;
C. 化工区来启动汽源;
D. 除氧器汽平衡母管;
【多选题】
汽轮机启动前高压启动油泵供___系统用油。
A. 各轴承冷却油;
B. 调速系统附加保安油;
C. 调速系统保安油;
D. 汽轮机挂闸油;
【多选题】
机组正常运行中定期工作涉及的内容大致可分为___几类
A. 运行设备与备用设备的定期切换或联锁试验;
B. 各容器液位保护的定期试验;
C. 汽轮机本体或重要辅助设备性能试验;
D. 各转动设备测振及油质检查;
【多选题】
汽轮机排汽装置漏入空气表现为___
A. 汽轮机真空偏低;
B. 机组真空严密性降低;
C. 凝结水过冷度增加;
D. 凝结水含氧量升高;
【多选题】
辅机启动前检查项目有___
A. 检修工作结束,工作票收回,检修杂物已清理
B. 手动盘车灵活无卡涩,启动前无倒转现象;
C. 各润滑部位油质、油位、油温正常,冷却水正常
D. 转向正确,绝缘合格
【多选题】
转动设备所处的状态有___
A. 检修
B. 运行
C. 紧急备用
D. 备用
【多选题】
辅机启动后的检查项目有___
A. 轴承温度、振动合格,窜轴≯2-4mm;
B. 电动机温升、电流正常,无异音;
C. 辅机密封水、冷却水、润滑油无泄漏;
D. 装置机械、系统连接正常,处理正常;
【多选题】
工业冷却水DLS型滤水器的反洗方式有___
A. 手动反冲洗
B. 定时反冲洗
C. 底部排污反冲洗
D. 自动反冲洗
【多选题】
顶轴油压低的原因有___
A. 顶轴油泵入口压力低或入口滤网堵塞;
B. 顶轴油泵旁通阀误开或开度过大;
C. 安全阀整定不当;
D. 顶轴油泵出入口阀开启不够;
【多选题】
运行中EH油母管压力下降的原因有___
A. EH油泵出、入口滤网堵塞;
B. EH油系统泄漏;
C. EH油泵跳闸或变量机构故障;
D. EH油系统安全溢油阀失灵;
【多选题】
低压加热器水位保护试验的目的是___
A. 检验水位保护动作值的正确性;
B. 检验水位感受元件的可靠性;
C. 检验信号传送元件的可靠性;
D. 检验执行元件的可靠性;
【多选题】
凝结水泵气化或漏入空气的现象有___
A. 凝结泵出口压力、流量摆动,或到“0”;
B. 电流下降或摆动;
C. 泵体声音异常,出口母管振动,发出撞击声;
D. 凝结水含氧量可能升高;
【多选题】
热井液位高的原因有___
A. 运行中凝结水再循环、高(低)减温水、低压缸喷水减温未关;
B. 热井补水门误开;
C. 凝结泵出力不足或出入口阀阀芯脱落;
D. 备用泵出口逆止门关闭不严;
【多选题】
高压加热器禁止投入的条件是___
A. 液位计失灵,无法监视水位;
B. 高加泄漏或疏水门卡涩;
C. I、II段抽汽逆止门卡涩;
D. 高加液位保护或抽汽逆止门保护试验不合格;
【多选题】
高压加热器上端差增大,进、出口给水温升减小的原因有___
A. 高压加热器旁路门关闭不严;
B. 高压加热器汽侧积聚有空气;
C. 高压加热器水侧换热管泄漏或无水位运行;
D. 高加水室垫子损坏,水侧短路;
【多选题】
汽轮机被压升高的原因有___
A. 环境温度过高;
B. 水环真空泵工作失常;
C. 机组负荷高
D. 轴加无水位运行;
【多选题】
主油箱油位正常,油压下降可能的原因有___
A. 主油泵工作失常;
B. 供、回油管路破裂;
C. 溢油阀定值不适
D. 交、直流油泵出口逆止门不严;
【多选题】
润滑油压正常,主油箱油位下降可能的原因有___
A. 润滑油回油管漏油;
B. 误开油箱事故放油门、取样门、油箱放水门;
C. 轴承严重漏油
D. 油净化装置跑油;
【多选题】
油系统着火时,可用___来灭火。
A. 干式灭火器;
B. 二氧化碳灭火器;
C. 1211灭火器
D. 泡沫灭火器;
【多选题】
电动机及油泵着火时,可用___来灭火。
A. 干式灭火器;
B. 二氧化碳灭火器;
C. 1211灭火器
D. 干砂灭火器;
【多选题】
汽轮机发生水冲击的原因可能是___
A. 锅炉满水或减温水调整不当,或误开减温水门;
B. 汽包压力急剧下降,造成蒸汽带水;
C. 高、低压加热器及轴封加热器泄漏、疏水不畅;
D. 机组负荷突变;
【多选题】
汽轮机发生大轴弯曲可能的原因有___
A. 启动前转子偏心度严重超标;
B. 上、下缸温差大;
C. 机组振动超规定时,未立即打闸停机;
D. 汽缸进冷汽、冷水;
【多选题】
汽轮发电机组轴承温度高可能的原因有___
A. 润滑油温度高或压力低,油质不合格;
B. 轴承动静部分磨擦;
C. 轴封漏汽过大;
D. 振动引起油膜破坏,润滑不良;
【多选题】
汽轮机背压升高可能的原因有___
A. 空冷翅片严重泄漏;
B. 空冷翅片脏污严重;
C. 轴封压力过低;
D. 轴加无水位运行;
【多选题】
蒸汽品质不合格,汽轮机通流部分静叶严重结垢,可能导致汽轮机___
A. 汽轮机效率下降;
B. 轴向位移增加;
C. 调节级压力升高;
D. 轴向间隙减小;
【多选题】
衡量调节系统动态特性的指标有___
A. 稳定性
B. 动态超调量
C. 过渡过程时间
D. 速度变动率
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