问题 问答题 简答题

何谓差压变送器的静压误差?它产生的原因是什么?

答案

参考答案:

①向差压变送器正、负压室同时输入相同的压力时,变送器的输出零位会产生偏移,偏移值随着静压的增加而发生变化,这种由于静压而产生的误差,称为静压误差.

②产生静压误差的原因主要是:

a.正、负压室膜盒有效面积不相等

b.出轴密封装置的波纹管或膜片与主杠杆不同心,存在偏心距

c.固定支架的螺钉上力不均,致使主杠杆和机座不垂直

d.仪表装配不合适,如大小机体的固定螺钉受力不均,下杠杆和“C”形簧片装配不正等

完形填空

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第二节 完形填空(共20小题;每小题1.5分,共30分)

阅读下面短文,掌握其大意,从每题所给的A、B、C、D四个选项中,选出最佳选项。

I had spent five exhausting years on my essay for my Ph. D.and was anxiously preparing for my oral boards (口头答辩)which were to be held in California, and I had  36  a flight through Minneapolis, where I was to change  37  .My flight was very late, and I was soon in an all-out run to  38  my flight. I had to stop to catch my  39  on a moving sidewalk when I  40  a woman in her fifties  41  with a carry-on bag.

I don't know  42  , but I looked at her face and blurted out, “Are you going on Flight 567 to California?”

She responded, “Yes.”

“So am I,” I responded. “Give me your bag. I'll run  43  and tell them to wait for you.” I took her bag and began running again.

I  44  onto the plane and told a flight attendant that one more passenger was behind me and to please  45  the plane for her. I  46  myself with her bag, and a few moments later she

arrived and was the last person on the plane  47  they closed the doors and it  48  . After the plane leveled off, I  49  the bag to her, and she smiled at me and thanked me.

I didn't sleep a wink in the hotel and arrived at the  50  at seven o'clock in the morning. The  51  kept me waiting for an hour in a room. I walked into the boardroom and was initially frightened by all the  52  in their robes(长袍). As I slowly  53  at the faces of all the board members, I noticed the bright face of a woman. She gave me a smile  54  a young schoolgirl. It was the same woman whose bag I had carried ahead the night before.  55  , whenever I made a mistake on any question, she did a great job of relaxing me.

36. A.prepared     B.caught         C.scheduled  D.bought

37.A.trains          B.buses         C.planes       D.directions

38.A.catch     B.run           C.get        D.hold

39.A.flight          B.breath          C.bag       D.companion

40.A.greeted     B.met          C.noticed     D.sought

41.A.walking    B.struggling     C.carrying    D.dashing

42.A.how     B.why         C.what      D.where

43.A.suddenly   B.immediately     C.fast       D.ahead

44.A.raced     B.got           C.solved      D.opened

45.A.leave     B.hold         C.remain      D.stay

46.A.found       B.took         C.seated       D.occupied

47.A.after     B.when         C.while      D.before

48.A.left out     B.set off         C.took off    D.started off

49.A.presented  B.sent          C.proved      D.showed

50.A.place     B.university     C.palace       D.museum

51.A.meeting    B.board              C.essay      D.argument

52.A.professors B.assistants      C.teachers    D.employees

53.A.started      B.watched       C.glanced     D.glared

54.A.like      B.as             C.of         D.from

55.A.In the end B.No matter how C.What's more     D.Needless to say

判断题