Page 8 - Troubleshooting Paper Mill Hydraulics Sample Excerpt 2

No. 3 P.M. Winder Power Supply and Rider Roll

9 Recirculation Filter

The oil that exhausts out of the no. 7 pump is ported through this filter
before returning back to the tank through the no. 10 heat exchanger.
The element’s condition should be checked regularly with the visual
indicator. The element should be changed on a regular scheduled
basis. This schedule can be established by an oil analysis program. If
the element plugs up and the inlet pressure reaches the setting of the
internal check valve, oil will bypass the element.

No. 9 Filter

10 Heat Exchanger

The no. 7 pump volume is constantly re-circulated over the tubes
inside the shell of this heat exchanger. The water flow is ported
through the tubes in the opposite direction. The heat in the oil is
transferred from the oil to the water. To achieve the most efficient heat
transfer the water flow should be 25% of the oil flow. The water flow is
controlled by a manual valve. Circulating hot wash oil or light
distillate through the tube side or shell side will usually effectively
remove sludge or similar soft deposits. Soft salt deposits may be
washed out by circulating hot fresh water. Some cleaning
compounds such as “Oakite” or Dowell” may be effective in removing
more stubborn deposits.

Page 38 Troubleshooting Papermill Hydraulics