Reel spools are critical components in the efficiency and productivity of the paper manufacturing process.
These cylindrical drums are used for winding and storing paper, paperboard, or tissue after they have been produced and are in the process of being converted into finished product
With so many moving parts and constant stress being applied to the reel spools, continuous inspections are a key factor in improving their lifecycles and maintaining high-quality finished products. One of the most effective strategies for achieving this is through the implementation of periodic phased-array nondestructive testing (PAUT).
Reel spools are positioned at the dry end of the paper machine, serving as the final point of interaction between the product and the production equipment. Because the goal is to maintain continuous operation of the paper machine, there are multiple reel spools in operation.
This includes a reel spool on the rewinder, a couple on the rails, one spooling, one ready for turn-up, and a few more waiting on a top rail above. The reel spools are continuously cycling through this process, moving from one area to the next.
Modern paper machines are able to operate in a semi-automatic mode, where the paper is seamlessly produced using the turn-up process (as one reel spool becomes full, another reel spool is “on deck,” ready to fall into place and begin spooling).
Once a reel spool is fully-loaded, a crane will pick it up and move it to the next stage of production. Considering that a single, fully-loaded reel spool can weigh several tons, the operational demands placed on them are immense. This weight is particularly concentrated on the reel spool journals, which endure significant stress while being moved, potentially leading to critical failures if not properly maintained.
The proper method of maintaining a reel spool is to tear it down and ship it to a third party for repairs as part of a maintenance schedule. When the reel spool is sent out, it will be fully disassembled, inspected mechanically and nondestructively, reassembled with any new needed parts, and shipped back to the owner.
This is a lengthy “as needed” process that consumes significant resources and time. A Kadant Johnson reel spool nondestructive test identifies potential failures in the reel spool, allowing the paper mill to schedule these roll tear downs as needed. Implementing a Kadant Johnson reel spool nondestructive test between third party tear downs as part of the maintenance schedule ensures the reel spools are operating safely and efficiently, eliminating unplanned downtime.
Phased-array ultrasonic testing is a proactive maintenance approach, that involves interrogating the volume of the journals with sound waves. These sound waves are introduced by a transducer that is manipulated along the exposed journal face.
This inspection is performed on-site without requiring tear down of the reel spool or stopping production. Phased-array ultrasonic testing is recommended yearly, between scheduled maintenance intervals to catch any issues before they become major problems. Reel spools flagged during phased-array ultrasonic testing can then be scheduled for a full nondestructive testing examination.