Features:
1) Wide adjustment range of loading for top roller, the pressures are more stable
and reliable
a) On the basis of reserving initial three-stage pressures, adding another stage,
half unloading (60N per two spindles), on the front loading element of YJ2-142C
arms. When a spinning frame is shut down for a long time, the stage is used to
decrease the pressure on the top front roller, and to avoid forming concave and