如何从风阀的排气声音判断跳汰机矸石段与中煤段的周期情况？
参考答案：在正常情况下，跳汰机矸石段与中煤段周期相差1800，两段的排气相隔时间相等，但矸石段排气声音较中煤段重，这是由于矸石段床层厚而中煤段床层薄所致。但是，有时由于检查修理或更换风阀联轴器的时候，一时不注意将一、二段风阀角度对错破坏了对称关系，这时风阀的排气声音是一声重音接一声轻音，然后间隔一定时间又是一声重音接一声轻音。遇此情况，必须及时调整，否则对分选不利。因矸石段溢流出来的物料进入中煤段以后，还未来得及稳定，就马上被中煤段上升力所鼓动，造成在中煤段物料前松后紧，既减少了分选机会，又产生了物料堆积，最终影响产品质量。
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| The next week, the man called Jimmy Calkins next to me raised his hand and volunteered this story: While making my list, I remembered an incident from high school. I 1 in a small town in Iowa. There was a sheriff (警长) in town that 2 of us kids liked. One night, my two friends and I 3 to play a trick on Sheriff Brown. After drinking a few beers, we found a can of red 4 , climbed the tall water tank in the middle of town, and 5 on the tank in bright red letters: Sheriff Brown is an S.O.B. (脏话). The next day, the town arose to 6 our glorious sign. 7 two hours, Sheriff Brown had my two friends and me in his office. My friends 8 but I lied, refusing to tell the truth. I had thought no one ever found out. Nearly 20 years later, Sheriff Brown's name 9 on my list. I didn't even know if he was still alive. Last weekend, I dialed the 10 in my hometown back in Iowa. Sure enough, there was a Roger Brown still 11 . I dialed his number. After a few 12 , I heard:"Hello?" I said:"Sheriff Brown?" Pause. " 13 ." "Well, this is Jimmy Calkins. And I want you to know that I did it." Pause. "I 14 it!" he cried. We had a good laugh and a lively 15 . His closing words were:"Jimmy, I always felt 16 for you because your friends got 17 off their chest, which I knew you were carrying around all these years. I want to thank you for calling me...for your sake (好处)." Jimmy 18 me to clear up all 101 pieces on my list. It took me almost two years, but became a true 19 for my career as a conflict mediator (矛盾调解者). No matter how 20 the conflict, crisis (危机) or situation is, I always remember that it's never too late to clear up the past and begin a new life. | ||||
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