Page 10 - Troubleshooting Paper Mill Hydraulics Sample Excerpt 2
P. 10
No. 3 P.M. Winder Power Supply and Rider Roll
13 Pressure Reducing Relieving Valve
This valve will reduce the system pressure down in the full piston
sides of the Rider Roll cylinders to the setting of the valve spring. The
spring setting of this valve is determined by either the no. 15 or no. 17
relief valves. The spool will shift between fully open and fully closed
allowing only enough oil flow through the valve to maintain the spring
setting. If the pressure exceeds the spring setting, the valve will shift
into the relieving mode. The pressure will be ported back to the tank
through the valve spool until it drops once again to the spring setting.
No. 13 Reducing Relieving Valve
14 Directional Valve
The RRX-SV solenoid is energized in the winding paper mode and
shifts the spool into the “A” (straight arrows) position. Oil is directed
through the “P” and “A” ports of the spool, through the no. 16 flow
control and into the no. 17 relief valve. The oil at the no. 15 relief valve
returns to the tank through the “B” and “T” ports of the valve.
Page 40 Troubleshooting Papermill Hydraulics
