锅炉容量对锅炉整体布置有什么要求？
参考答案：
（1）随着锅炉容量的增大，炉膛的线性尺寸增加，炉膛壁表面积增大比容积增大得少。因此大容量锅炉比小容量锅炉的炉膛壁表面积相对减小，此时在炉膛内单靠布置水冷壁己不能有效降低炉膛出口烟温，所以一些大容量锅炉采用了双面水冷壁或增设辐射式、半辐射式过热器来降低炉膛出口烟温到允许值。
（2）随着锅炉容量的增大，锅炉单位宽度上的蒸发量迅速增大。为了保证规定的过热汽流速和烟气流速，需采用多管圈的过热器和省煤器。管式空气预热器也应采用双面进风结构，防止风速过大。
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| A: 2576321 Guizhou Museum, this is Jenny speaking. How can I help you? B: Hi, I'd like to buy tickets for the Picasso Exhibition. I would like to know when I can go and how much the tickets are. A: Hum, let me see. The exhibition is open from 9:00 a.m. to 7:00 p.m.on weekdays, and from 3:00 p.m.to 9:00 p.m.on weekends. B: Weekdays, 9:00 a.m.to 7:00 p.m. on weekends, 3:00 p. m to 9:00 p.m, got it. Thank you. And what about the prices? A: It's$12 for adults, half for children, and one third for groups. B: I see. How many people do we need to have to make up a group? A: At least 6. B: I see. Do I have to order tickets now, or can I buy them when I get there? A: You can buy them here. The exhibition is on the second floor of the museum, Hall 3. B: Second floor, Hall 3. Thank you.
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