Press for forming large pipes has hydraulic cylinder including secondary piston in part of cylinder casing forming fast action cylinder

摘要

The press forms pre-formed U-shaped sheets into large slotted pipes. The hydraulic cylinder (1) includes a secondary piston (8) in part of the cylinder casing (6), forming a fast action cylinder. The secondary piston is on or in the main piston (7). Pressure lines (13, 14) lead to the surface (12) of the secondary piston and to the free annular surface (16) of the main piston.