Benefits of Core Joining & Paper Core Recycling

Every year the paper industry uses millions of cardboard and paper cores during the papermaking process. These cores come in all different sizes and grades.   In a typical parent core handling system for the Tissue Industry, these cores can weigh in at 100 pounds with a 16-inch diameter and each of these industrial-strength cardboard cylinders can carry a parent roll of paper up to 30 feet in circumference. Paper manufacturers reuse these cores repeatedly to avoid the high costs of disposal and replacement.  Traditional methods of crushing, repulping, making board, and cores are costly.

Core Cleaning & Broke Handling
Traditional core handling systems avoid salvaging these degraded cores, and operators discard damaged cores when they are detected.  To avoid damaging valuable machines by exposing them to the rigid core, manufacturers stop short of using the entire spool. This sizable “spent” left on the core can weigh anywhere from 200 to 300 pounds and is removed for recycling.

Core cleaning, roll slabbing and broke management are the automated processes of removing spent or waste material from the core and getting that material safely and efficiently back into the pulper.   The purpose of this article is not to describe those slabbing paper processes or core recycling by cutting down spending, but to briefly describe the core recycling by core joining and it’s benefits.​

Core Joining
Core Joining, Core Recycling, Core Splicing or Core Gluing are all similar terms to describe the process of removing the degraded or damaged portions of the paper cores and gluing or joining the remaining quality sections of the core back together. In many cases, the glued joints are stronger than the original when placed back into production. Deformed and damage core ends are just cut off, and the remaining healthy parts are joined together resulting in a quality core at a reduced cost.

The Process
Although Core Joining can work with multiple diameters of cores, the process of core joining is consistent.

  1. Core A is loaded into Core Joiner
  2. Core A leading deformed end is cutoff
  3. Core A trailing deformed end is cutoff and machined to a female cone
  4. Core B is loaded into Core Joiner
  5. Core B leading end is machined to male cone
  6. Adhesive is applied to Core B
  7. Core A and Core B are pressed together
  8. Core AB is cut to desired length
  9. Restart process using new core drop as new “Core A”

These systems also connect to machines upstream and downstream to help ensure uninterrupted production.  The converting process that turns the paper into the final product happens upstream from the core cleaner and must operate continuously to ensure production keeps up with demand.

Impact,  Savings, and Return on Investment

Recycled Core Durability

  • Recycled cores maintain their geometry (length, ID, and wall thickness)
  • Recycled cores maintain their strength (crush and torque testing)
  • Recycled cores do not have damaged ends and maintain their ability to properly chuck

Paper Mill Core Recycling
Recycling cores saves energy, helps keep materials out of landfills and incinerators, and provides new cores for the production of new parent rolls. When waste cannot be prevented, recycling is the next best option. Core recycling by core joining is more than extending the life of cores, conserving water, energy, land and raw materials – it is also about saving money.  Such systems can reduce new core purchases significantly.