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Winders require a consistent preventive maintenance program (PMP)
Sheet breaks at the winder can bring the entire papermaking process to a stop. To prevent this, the winder needs constant attention through a sound preventive maintenance program (PMP).
Insights ● Article
Stainless steel care, cleaning, surface prep and passivating
Stainless steel is corrosion resistant and maintains a film of chrome oxide over its surface. Under normal conditions this film is self-healing.
Insights ● Article
Optimize operations with a Roll Cover and Maintenance Agreement
Sending rolls to multiple suppliers can be expensive, cause a loss in continuity and create extra burdens for roll management. A roll agreement will help.
Insights ● Article
Reading fluids circuit diagrams - hydraulic & pneumatic symbols
Reading hydraulic and pneumatic circuit diagrams and being able to make sense out of them is a valuable skill for mill personnel. The first article in this series presents fluid control elements.
Insights ● Article
Reel backlash due to worn parts causes sheet breaks, case study
Sheet breaks on PM1 are costing thousands of dollars. Valmet emergency service discovers backlash and further analysis provides temporary and long-term fixes.
Insights ● Article
Troubleshooting roll bouncing addresses the four probable causes
Roll vibration can intensify enough to actually bounce the rolls, causing an unsafe situation at the winder. The most common causes are mechanical hardware, controls, roll structure and paper properties. Thorough troubleshooting is the best recommendation.
Insights ● Article
Solutions to multiple poly roll cover failures, a case study
After blowing two expensive roll covers, a mill asked Valmet to investigate. After checking roll history, nip impressions and coolant, the culprit was an inexpensive part.
Insights ● Article
Common hydraulic valves – cartridge counterbalance valves
Counterbalance valves prevent oil from leaving a cylinder that is holding a load. Without them, loads would move uncontrollably if oil pressure is lost.
Insights ● Article
Size press roll wear causes reel wrinkles and culls, a case study
A P&W paper machine suffered from excess wear on the back edge of the bottom size press roll. The problem was traced to the size press synchronization shaft. When the shaft was replaced, the roll wear problem went away.
Insights ● Article
Five checks at shutdown when inspecting rubber covered rolls
At a shutdown, to determine if the cover should be taken out of service for either regrind or recover, inspect the cover for these five issues.
Insights ● Article
