Friction installations of up and down roller will help reduce resistance and lower power consumption.

上下压轮装置采用滚动摩擦，有利于减少工作阻力，降低功率消耗。

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The upper and down working rollers of rolling machine are installed in the middle of the housing window through upper and down roller base.

轧机的上、下工作辊通过上、下工作辊轴承座安装在牌坊的中部。

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Stock prices took a roller-coaster ride this week -- down one day,up the next.

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In some parts of the city, hawkers, newspaper delivery boys, roller-skaters, even those who carelessly kicked a tin can down the street were targeted.

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Softball, squash, baseball, karate and roller sports all bid to be accepted as Olympic sports but were turned down by the executive board two months ago.

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