【单选题】Panama lies between North and South America. It has an area of 77,000 square kilometers with a population of 1 ,771,000. Its official language is Spanish. Its capital is the largest city. Panama City....
A.
from the 16th century to the 18th century
D.
for 300 years and more
【判断题】普通压延机精度较低,生产效率不高,压延制品尺寸误差较大。
【判断题】辊筒直径和压延制品的宽度越大,所产生的横压力也越大。
【单选题】Panama lies between North and South America. It has an area of 77,000 square kilometers with a population of 1,771,000. Its official language is Spanish. Its capital is the largest city. Panama City. ...
A.
from the 16th century to the 18th century
D.
for 300 years and more
【多选题】解决压延制品中间高的问题,主要是从设备上着手,一般有:( )、( )和预应力。也可利用红外线向辊筒两端的塑料进行补偿加热,或是中间部分吹冷风来补偿处理。