问题 问答题 论述题

怎样判断变压器油面是否正常?出现假油面是什么原因?

答案

参考答案:

变压器的油面变化(排出渗漏油)取决于变压器的油温变化,因为油温的变化直接影响变压器油的体积,从而使油标内的油面上升或下降。

影响变压器油温的因素有负荷的变化、环境温度和冷却装置运行状况等。如果油温的变化是正常的,而油标管内油位不变化或变化异常,则说明油面是假的。

运行中出现假油面的原因可能有:油标管堵塞,呼吸器堵塞,防爆管通气孔堵塞等。

阅读理解

阅读理解。

     Jack is a twenty-year-old young man. Two years ago, when he finished middle school, he found

work in a shop. Usually he works until ten o'clock in the evening. He is very tired when he gets home.

After a quick supper he goes to bed and soon falls asleep. His grandma who lives downstairs is satisfied

with (满意) him.

     One day, on his way home, he met Mary. They were both happy. He asked the girl to his house, she

agreed happily. He bought some fruit and drinks for her. And they talked about their school, teachers,

classmates and their future (未来). They talked for a long time.

     "Have a look at your watch, please," said the girl. "What time is it now?"

     "Sorry, something is wrong with my watch," said Jack. "Where's yours?"

     "I left it at home."

     Jack thought for a moment and found a way. He began to stamp his foot on the floor, "Bang! Bang!

Bang!"

     The sound woke his grandma up. The old woman shouted downstairs, "It's twelve o'clock in the

night, Jack. Why are you still jumping upstairs?"

1. Jack was ________ when he finished middle school. 

A. sixteen  

B. eighteen  

C. twenty  

D. fifteen

2. The old woman is satisfied with Jack because ________. 

A. he's her grandson      

B. he's clever 

C. he can keep quiet      

D. he gets home on time

3. From the story, we can know that Mary is Jack's ________.

A. classmate      

B. colleague (同事)    

C. aunt      

D. wife

4. The word "stamp" in the story means ______ in Chinese. 

A. 盖印     

B. 跺     

C. 贴邮票     

D. 承认

5. Jack stamped his foot on the floor in order (为了) ________. 

A. to wake his grandma up 

B. to make his grandma angry 

C. that his grandma was going to tell him the time 

D. that his grandma was going to buy him a watch

单项选择题