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Objectives:

Spool waste under control and rolls the right size. Spool waste under control and rolls the right size. Spool waste under control and rolls the right size.

The Solution:

PLC based WINDER control system

 Description

 System features

 Proven results

 Easy operation

 Reports

 Low cost

 

• DESCRIPTION

Large reels cause excessive losses. There is abundant paper on these reels to make the sets that are required. But the leftover paper has to be recycled. This leftover paper should be on the next reel and where it could be sold rather than recycled.

Small reels also cause excessive losses. Small reels produce one or more sets that are smaller than they could be. Less tonnage is shipped per production run. And customers are unhappy because of inconsistent roll sizes.

The ideal is to produce reels of precisely the right size to result in maximum size sets and leave minimum spool waste. Productivity and profit are maximized and losses are minimized.

The ideal is approached by a closed loop system utilizing a laser sensor. The sensor detects the diameter of sets as they are made in the winder. The system analyzes the reel as it unwinds and the sets as they are wound, and it will automatically adjust the size of the next reel as needed.  This is the basis of Nall Engineering's system.  Scroll down to see the features.

SYSTEM FEATURES                                                                                                 To top

For backtender

• Touch screen control terminal
• One button entry for standard parameters
• One-time setup for long runs
• Signal for automatic or manual turn-up
• Broken reel analysis capability
• Suspicious data entry alert

For winder operator

• Touch screen control terminal
• One button entry for standard parameters
• One-time setup for long runs
• Suspicious data entry alert
• Winder auto stop
• Auto stop at a reel inch set point
• Three selectable winder modes

1. 1. 1. Equal sets mode: operator selects nominal diameter for rolls. The system calculates appropriate diameter set point to divide the reel into equal sets and leave the specified spool waste. The system auto stops the winder at the laser- measured diameter.
      2. Diameter mode: operator sets desired roll diameter. The system auto stops the winder at the laser- measured diameter.
      3. Length mode: operator sets desired roll length. The system auto stops the winder at the set length.

Closed loop

Laser measurement feedback is used to automatically adjust reels sizes to maintain good roll diameters at the winder and keep spool waste low.

Options

• A reel/spool tracking feature is available to convey reel information to the winder operator. This option also enables the system to continually self-calibrate so that paper machine reels and winder rolls agree on the length of a foot. This is needed to consistently achieve proper roll lengths and leave low spool waste when winder rolls are made to length.
• A reporting feature accumulates data in 24-hour blocks for printed reports regarding production, reel sizes, roll sizes, spool waste, operator performance, downtime, etc.

PROVEN RESULTS                                                                                                     To top

Actual production data for ten typical reels are tabulated below. The figures are in inches. At the beginning of the run of 40" sets the winder operator simply pressed a Panelview button to select the 40" nominal diameter, one time, at the beginning of the first set set 40" rolls. No other setup changes were needed for the run.  The operator thereafter did nothing but install cores and start the winder until different nominal diameter was to be run.  The system calculated and automatically used the proper diameter set point for each set of rolls. When the first reel for 45" nominal diameter sets arrived at the winder, the winder operator pressed the button to change to the 45" diameter. Major spool waste and variation in roll diameters can result from backtenders and winder operators "estimating" reel and roll size set points. This system removes the guesswork.

Tabulation of rolls produced from ten other reels:

EASY OPERATION                                                                                                 To top

Ease of operation was a primary consideration in the design of the system. Standard input parameters are activated by single pushbuttons. Numeric keypads are used only when special sizes are needed.

Backtender procedures

• Select core size to be used in winder if different from previous reel
• Select roll sizes expected at winder if different from previous reel
• Turn up when the system signals

 

Winder operator procedures

• Select core size if different from previous selection
• Select roll size if different from previous selection
• Start winder normally
• Winder stops automatically

REPORTS                                                                                                             To top

The system accumulates reel and winder production data for 24-hour periods. At a preset time the accumulated data is moved to a memory storage block where is retained for 24 hours. It will be overwritten by the succeeding block of data in the succeeding 24 hours. The current block of data can be retrieved at anytime for display on an Excel spreadsheet.  A sample report follows.

  LOW COST                                                                                                         To top

The system cost is low because it utilizes off-the-shelf products readily available from major manufacturers. The original design used an Allen-Bradley PLC5 programmable controller. Any PLC that can emulate the PLC5 can do the job. No custom design hardware is used at all in the system. The buyer can go directly to the control vendor for parts. Any competent PLC technician will be able to troubleshoot the system.

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