BJ-400P type middle speed automatic paper disc machine widely used in the production of paper or aluminum foil as raw materials of the disc child.

These springs are called torsional springs. They let the middle part of the clutch disc turn slightly on the hub. Thus, the springs absorb the torsional vibrations of the crankshaft.

One side of the middle part of the outer shell below the milling disc of the layer is provided with a discharge port.