问题 问答题 简答题

弹簧为什么易断裂?

答案

参考答案:

1)使用时间超过其设计寿命,正常疲劳断裂。

2)弹簧材质与弹簧力选择与工况不符。

3)维修、组装时弹簧没有被正确的安装或弹簧本身有缺陷。

4)新弹簧与旧弹簧同时装在一个气阀内。

阅读理解

A thief entered the bedroom of the 30th President of the United States, who met him and helped him escape punishment.

The event happened in the early morning hours in one of the first days when Calvin Coolidge came into power, late in August, 1923. He and his family were living in the same third-floor suite(套房) at the Willard Hotel in Washington that had occupied several years before. The former President’s wife was still living in the White House.

Coolidge awoke to see a stranger go through his clothes, remove a wallet and a watch chain.

Coolidge spoke, “ I wish you wouldn’t take that.”

The thief, gaining his voice, said, “ Why?”

“ I don’t mean the watch and chain, only the charm(表坠). Take it near the window and read what is impressed on its back,” the president said.

The thief read, “ Presented to Calvin Coolidge.”

“ Are you President Coolidge?” he asked.

The president answered, “ Yes, and the House of Representatives(众议院)gave me the watch charm. I’m fond of it. It would do you no good. You want money. Let’s talk this over.”

Holding up the wallet, the young man said in a low voice, “ I’ll take this and leave everything else.”

Coolidge, knowing there was 80 dollars in it, persuaded the young man to sit down and talk. He told the President he and his college roommate had overspent during their holiday and did not have enough money to pay their hotel bill.

Coolidge added up the roommate and two rail tickets back to the college. Then he counted out 32 dollars and said it was a loan(借款).

He then told the young man, “ There is a guard in the corridor.” The young man nodded and left through the same window as he had entered.

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