How a Water Jet Reel Turn-up System Reduces Bottom Broke and Improves Turn-up Reliability

As paper machine speeds increase, the reel turn-up process places higher demands on action timing, reel-spool surface speed, nip conditions, and web control. On some high-speed machines and certain paper grades, conventional pneumatic turn-up, tape turn-up, or methods that rely heavily on manual intervention may result in unstable turn-ups, increased bottom broke, and more cleanup work. This article explains why higher machine speeds make reel turn-up more difficult, how a water jet reel turn-up system is configured and operates, which paper grades it can handle, and the key conditions that should be evaluated when considering a retrofit.

Why Reel Turn-up Becomes More Difficult as Paper Machine Speed Increases

Modern paper machines continue to move toward higher operating speeds and wider machine widths. Some high-output machines run at more than 1,000 m/min. Under these conditions, the paper web moves continuously through the reel section at high speed, leaving a much shorter time window for the turn-up sequence. This places higher demands on new reel-spool speed matching, the nip between the reel spool and reel drum, web tension, and synchronization of the turn-up equipment.

At lower machine speeds, some paper machines can maintain production with manual assistance, pneumatic turn-up, or other conventional methods. As speed increases, however, any delay in the sequence, unsuitable cutting path, mismatch in new reel-spool speed, or unreliable web attachment can lead to a failed turn-up, web break, or excessive wrinkles and broke in the first layers of the new roll.

The higher the paper machine speed, the greater the paper loss caused by the same few seconds of turn-up delay or failure. On machines that perform multiple reel changes per shift, this bottom broke, cleanup time, and production loss can accumulate significantly over time.

The Hidden Costs of Unstable Reel Turn-up

When the turn-up process requires significant manual intervention, or when the existing turn-up device is not sufficiently stable, the impact is not limited to the waste generated during the reel change itself. It can also affect bottom-roll quality, paper machine operating efficiency, and on-site safety management.

Paper and Production Losses

Before a reel change, the new reel spool must be positioned, accelerated, brought into the correct nip condition, prepared for web attachment, and then the turn-up sequence must be executed. If any step takes too long or is not properly coordinated, the time during which the web fails to transfer correctly onto the new reel spool increases. On a high-speed paper machine, even a few additional seconds can create substantial bottom broke, and the cumulative loss becomes more significant after multiple reel changes each day.

 If a turn-up fails, the paper machine may need to slow down, operators may have to remove loose or flying paper, or the web may need to be rethreaded. This results in additional paper loss, cleanup work, and production downtime. Therefore, a turn-up system should be evaluated not only by its turn-up success rate, but also by bottom broke, web-break risk, and recovery time.

Operator Safety

During manually assisted turn-up or removal of loose paper, personnel may need to work close to high-speed rotating reel spools, paper rolls, and moving mechanisms. An automated water jet reel turn-up system can reduce manual intervention at the moment of turn-up, but it must still be used together with the reel safety guarding, emergency stops, interlocks, and site operating procedures. Automation should not be described as eliminating all safety risks.

Reduced Paper Machine Availability

Every failed turn-up, extended turn-up cycle, or web break after a reel change reduces effective paper machine operating time and production output. On continuous paper production lines, repeated small delays in the reel section can gradually reduce overall machine efficiency.

How a Water Jet Reel Turn-up System Works

A complete water jet reel turn-up system normally includes more than the high-pressure water cutting device. It also includes a traversing nozzle beam, a web-tail pick-up and attachment device (or another suitable turn-up assist method), a high-pressure water supply unit, and a servo drive and control system. The water jets cut the moving web along a programmed path, while reliable transfer of the web tail to the new reel spool also depends on the attachment method, sequence timing, and mechanical condition of the reel. A typical operating sequence is as follows:

Step 1 - Prepare the Turn-up Conditions

When the finished roll approaches the preset diameter, the water jet reel turn-up system receives a turn-up command from the reel or the DCS/PLC. The new reel spool should already be in position and accelerated, and its surface speed, nip condition, web-attachment device, and safety interlocks must be confirmed to meet the turn-up requirements. The turn-up can be completed at normal production speed, but whether a speed reduction is required should be determined according to the paper grade, reel design, and site commissioning results.

Step 2 - Cut the Web with High-pressure Water Jets

In a typical dual-nozzle configuration, two high-pressure water-jet nozzles create the initial web tail according to the programmed sequence and then travel in the cross-machine direction, progressively widening the cut. Depending on the paper grade, cross-cutting, parallel cutting, or other dedicated cutting paths may also be used. High-pressure water cuts the moving web without mechanical contact. Nozzle pressure, orifice size, traversing speed, and cutting path must be commissioned according to paper grade, basis weight, machine speed, and web strength; a single fixed pressure value cannot represent all applications.

Step 3 - Attach the Web Tail and Build the New Roll

The initial web tail created by the cut must be reliably attached to the new reel spool by means of adhesive, turn-up sealant, a web-tail pick-up mechanism, or another method compatible with the reel. The two nozzles then continue to widen the cut so that the web opens smoothly from the center toward both sides and winds onto the new spool layer by layer. Proper symmetrical cutting and sequence control can help reduce wrinkles in the first layers, diameter variation, and bottom broke, but they should not be described as absolutely eliminating wrinkles or defects. Turn-up success also depends on reel-spool speed, nip load, web tension, attachment performance, and the mechanical condition of the reel.

Which Paper Grades Are Suitable for Automatic Water Jet Reel Turn-up?

Water jet reel turn-up technology can be applied to a wide range of paper and board grades, but suitability cannot be determined solely by the paper-grade name. The final solution should be evaluated according to basis weight, machine speed, web width, web strength, reel design, new reel-spool surface condition, available installation space, and the existing control system. Typical applications include:

1.Fluting, linerboard, kraft liner, and testliner - these heavier grades generally place greater emphasis on reliable cutting, smooth first-layer build-up, and reduced bottom broke.

2.White board, coated board, and other paperboard grades - the cutting path and turn-up method should be selected according to basis weight, coating characteristics, and web strength.

3.Newsprint, printing and writing paper - on high-speed machines, greater attention is typically paid to turn-up success rate, paper machine efficiency, and bottom-roll quality.

4.Tissue - because the web is light, soft, and relatively low in strength, dedicated cutting paths, attachment methods, and more precise parameter control are normally required.

For medium- and high-speed paper machines, especially production lines with unstable turn-up performance, high bottom broke, or significant manual cleanup requirements, a water jet reel turn-up system is worth technical evaluation. However, suitability and the expected level of improvement should be determined from actual site data, reel drawings, paper-grade parameters, and analysis of existing turn-up problems.

Although reel turn-up is only a brief stage in papermaking, it directly affects bottom broke, paper machine output, roll quality, and on-site safety management. A properly designed water jet reel turn-up system that is correctly integrated with the reel can improve turn-up consistency through non-contact cutting, symmetrical web widening, and automatic sequence control, while reducing manual intervention and bottom broke.

Q1: What paper machine speeds are suitable for a water jet reel turn-up system?

A:There is no single minimum machine-speed threshold for applying a water jet reel turn-up system. The higher the speed, the more significant the losses caused by turn-up timing errors usually become. However, a medium-speed machine may also benefit from a retrofit if it suffers from low turn-up success rates, excessive bottom broke, frequent flying paper, or heavy manual intervention. The decision should be based on paper grade, machine width, reel design, and current turn-up performance.

Q2: Can a water jet reel turn-up system be retrofitted to an existing paper machine?

A:Most projects can be retrofitted to an existing reel, but the CAD drawings and actual site dimensions must first be checked. The installation position of the nozzle beam, support structure, movement clearance, high-pressure water piping, electrical interfaces, turn-up signals, safety interlocks, and maintenance access must all be confirmed. Some sites may require additional brackets or platforms, or local modification of existing components.

Q3: What is the difference between water jet reel turn-up and tape turn-up?

A:Both methods can achieve automatic reel turn-up. A tape turn-up system typically feeds a disposable turn-up tape into the nip between the reel drum and the new reel spool, using the tape to sever the web and carry it onto the new spool. A water jet reel turn-up system uses high-pressure water to cut the web along a programmed path and transfers the web tail using adhesive, a pick-up device, or another auxiliary method. Water jet turn-up generally supports a more symmetrical first-layer build-up and can reduce tape marks and consumable use, but it requires a high-pressure water system, filtration, and nozzle maintenance.

Q4: What maintenance does a water jet reel turn-up system require?

A:Routine maintenance should cover not only the high-pressure nozzles and high-pressure pump, but also water quality and filtration, intensifier or pump seals, high-pressure hoses and fittings, the nozzle traversing mechanism, servo drive, position sensors, adhesive or web-tail pick-up devices, and safety interlocks. Maintenance intervals should be established according to water quality, number of turn-ups, operating hours, and condition of critical components, and a formal inspection checklist should be created after commissioning.

Q5: Can the system be used on wide paper machines?

A:Yes. A water jet reel turn-up system can be customized according to web width and reel design. However, as the machine width increases, the requirements for beam rigidity, nozzle traversing speed, synchronization accuracy, hose management, and installation alignment become more demanding.

Q6: Can a failed turn-up damage the new reel spool?

A:Under normal design and interlock conditions, the water-jet cutting process does not mechanically contact the new reel spool, so the risk of directly damaging the spool is relatively low. However, a failed turn-up may still cause loose or flying paper, web wrapping, abnormal bottom-roll formation, or shutdown cleanup. The actual consequences depend on the cause of the failure and the condition of the reel.