Due to the location of the three roller can rely on the close, to achieve a smalldiametertube and rolling round the school.
由于三个辊子位置可以靠的很近，能够实现小筒径卷制和校圆。
2
A tube of small internal diameter; holds liquid by capillary action.
一种有很短直径的管道；通过毛细管作用来盛液体。
3
Burn through is the main problem of longitudinal seam welding of ultra-thin tube with smalldiameter. Assembly of the joint and welding technology are the key to solve the problem.