【单选题】One method of determining crankshaft misalignment is by()
A.
laying a straight edge across the crank webs at the crankpin and measuring the distance to the crankpin in two places
B.
measuring the crank drop on either side of each crank throw while the crankshaft is slowly rotated through one revolution
C.
rotating the crankshaft through one revolution, pausing each 90oof rotation to measure bearing clearances, top and bottom
D.
taking micrometer reading between the crank cheeks opposite the crankpin every 90°of crank angle rotation
【单选题】为了( ),在贮存和使用易燃液体的区域必须要有良好的通风。
【单选题】In a four-stroke/cycle diesel engine, the camshaft rotates at _____.
A.
twice the crankshaft speed
B.
half the crankshaft speed
C.
the same speed as that of the crankshaft
D.
a speed independent of that of the crankshaft
【判断题】交易勋章根据供应商近90天在线交易金额进行统计,只要近90天内通过支付宝交易过商品并交易成功的,即可获得交易勋章。
【单选题】40g吐温80 (HLB为15)与60g司盘80 (HLB为4.3)混合后HLB为
【单选题】40g吐温80(HLB为15)与60g司盘(HLB为4.3)混合后HLB为( )
【简答题】为了( ),在贮存和使用易燃液体的区域必须要有良好的通风。
【判断题】机床中Z轴方向是于机床主轴平行的方向,正方向为刀具远离工件的方向。()