Paper Roll Production System Optimization
A company purchased a shuttered paper plant intending to convert production to a heavier liner board used in the manufacture of corrugated and folding cartons. The plant was originally outfitted to produce lightweight paper and would now need to produce paperboard stock as heavy as 280 lbs./3,000 sq. ft., in 20 ft. wide web rolls while still maintaining higher production speeds to remain cost-competitive. Although paper and board production systems are similar, there are significant differences in the design of recyclable edge trim removal systems and the ease of running at high production speeds.
The existing paper roll production system was outfitted with 6” intake tubes to the eductors, limiting the size of the trim that could be recovered from both sides as rolls were cut to size. The old paper system transferred 3” wide trim back to the pulper for recycling. Production systems for liner board operate in a similar fashion but must recover trim as wide as 12” per side. The heavier liner board stock also was more difficult to run at the same 6,000 ft/min as the old paper system ran.
Compass engineers determined that the old system could not be upgraded to recover up to 12” of trim from both sides of the roll and proposed a properly sized and engineered system to meet the needs of producing heavier liner board. This new system was Venturi-based using negative air pressure to vacuum trim off both sides of the web and was fitted with larger intake tubes to handle up to 12” wide trim ribbons. During the design phase, the decision was made to keep the existing 6,000 ft./min winder since it was in good working order and could meet production requirements. The new system, however, is capable of running at 7,500 ft./min. providing future flexibility to upgrade the system.
Compass designed the system, fabricated the necessary components, and shipped everything to the plant ready for installation. At that point, budgetary problems forced the materials to sit on-site for two years before installation.
When the call came to resume installation, Compass engineers were wary of forging ahead too quickly. Rather than take the easy way out, Compass engineers decided to remeasure space constraints and field test the 150 hp fans to make sure the long storage hadn’t put too much pressure on fan bearings throwing them out of balance.
These decisions proved fortuitous but increased pressure on Compass to complete installation within time constraints. A field survey found space constraints had changed, requiring the resizing of some significant structural members. However, all equipment was found to be in perfect working order, a testament to the quality of the original fabrication. With some extra effort, we were able to complete site inspections, replace structural members, install and test the system before the deadline.
An All (En)Compassing Turkey Project:
This project required single-point accountability, so Compass delivered a complete turnkey solution incorporating our Engineering, Fabrication, and Installation expertise.
Once it was determined that the old system could not be sufficiently upgraded to handle wider trim and heavier stock requirements, Compass crews tore down the old system and disposed of the scrap.
The entire integrated system was designed for reliable high-speed operation within budget constraints. We used a Venturi-based system proven effective in similar applications and custom-designed for this particular plant.
System components were fabricated in our plant using laser measurements taken at the customer’s plant. Controls were programmed, run, and debugged before delivery. All components were staged in our plant before shipment.
Working around the clock, with supervisors, Compass installation crews fully installed and tested the system on a tight schedule, completing our turnkey process.
The final system is capable of handling (2) 12” wide edge trims while running at 7,500 ft./min, however, it normally runs at no more than 6,000 ft/min due to the limitations of the winder remaining from the old system. This allows for future winder speed upgrades if required. While running at the same speed as the old lightweight paper system, the new system is capable of recovering up to 12” wide edge trim per side and recycling it to the pulper.
Once again, Compass pointed the way to more robust and efficient trim recycling costs.