Paper Machine Reel Systems

Key Questions

The following key questions are answered in this module:

How is the parent reel speed controlled if it is not driven?
The buiding parent reel is held against and driven by the driven reel drum, whose speed is matched to the rest of the paper or board machine.

What is ""double nip loading""?
"Double nip loading" occurs when both the primary arm hooks and the secondary arms are in contact with the spool, after the primary arms have set the spool on the rails and the secondary arms have loaded. A time-delay pressure switch is typically used to keep the double loading to a minimum.

Why are reel drums grooved?
Reel drums are often spiral grooved to allow the boundary layer air traveling with the sheet to evacuate and allow the sheet to lay flat on the drum.

How are reel spools started?
A driven rubber tire or belt accelerates the empty spool in the primary arms up to, or just above, the current machine speed before the spool is lowered to its turn-up position, on top of the reel drum.

Why are ""bubble"" turn-up systems only used on lower weight grades?
A bubble-type turn-up system uses a pocket of air blown in under the sheet just ahead of the reel to transfer the sheet to a new spool. The air ""bubble" is caught up in the reel drum/spool nip and the rotating spool pulls and tears the sheet. This works better on lighter weight sheets, which tear more easily.

Sample Video Transcript

Below is a transcript of the video sample provided for this module:

The purpose of the reel section, or simply the reel, is to wind the continuous sheet produced on a paper or board machine onto a spool to produce jumbo rolls called parent reels that are ready for further processing. It basically completes the paper or board production process. Most paper and board machines use pope reel systems, where the building parent reel is pressed against and driven by contact with the surface of a motor-driven reel drum. When the parent reel reaches its desired size, the reel system relies on a turn-up system to break the sheet and transfer it to a new spool. The reel also relies on a tail threading system to thread a tail from the dryers to the reel during start-ups, after sheet breaks, or after a disruption at the dry end.

Related Courses

Customer Q&A