问题 问答题 简答题

衬里管道安装时还有哪些其他要求?

答案

参考答案:

不得在衬里管道上进行任何焊接,也不允许用火焰进行加热,以防衬里层熔化或炸裂,衬里管道不允许再进行任何加工.加法兰、螺纹等都必须在衬里前焊接或加工好。

试运行时,升温或降温应力求缓慢,避免过大的温度急变。在任何情况下,绝对不允许超过许用工作温度的规定范围。

阅读理解

七选五(每小题2分, 满分10分) 根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项, 并在答题卡上将该项涂黑。选项中有两项为多余选项。

  When a starving man gets a meal,  he begins to think about an overcoat; when an executive(业务主管)gets a new sports car, visions of country clubs dance into view. The many wants of mankind might be regarded as making up several levels.    2 .The first and most basic levels of wants involve food. Once this want is satisfied, a second level of wants appears: clothing and some sort of shelter. By the end of World War II these wants were satisfied for a great majority of Americans.    3   It included such items as automobiles and new houses. By 1957 or 1958 this third level of wants was fairly well satisfied. Then, in the late 1950s a fourth level of wants appeared: the “life-enriching” level. While the other levels involve physical satisfaction-the feeding, comfort, safety, and transportation of the human body-this level stresses mental needs for recognition, achievement and happiness. It includes a variety of goods and services, many of which could be called “luxury”(奢侈) items. Among them are vacation trips, the best medical care, and entertainment.  4     On this level, a greater percentage of consumer spending goes to services, while on the first three levels more is spent on goods. Will consumers raise their sights to a fifth level of wants as their income increases, or will they continue to demand luxuries and personal services on the fourth level? A fifth level probably would involve wants that can be achieved best by community action. Consumers may be spending more on taxes to pay for government action against disease, ignorance, crime and prejudice.   5  In this way, we can enjoy more fully the good things on the first four levels.

A.Then a third level appeared.

B.Human wants seem endless.

C.When there is money enough to satisfy one level of wants, another level appears.

D.There are several levels of wants in one’s life.E.At this stage, we now may seek to ensure the health, safety, and leisure.

F.Also included here are fancy foods and the latest styles in clothing.

G.Different people have different wants on each level.

单项选择题