Pulp & Paper

The Fitch Company continues to provide electrical, instrument and process control engineering services to all process areas of the pulp and paper plants.  We have very specialized skills in many of these areas as can be seen by other project categories on our website.

 

 

Winder Controls

The Fitch Company engineers have in-depth experience with both two-drum and single-drum winders from multiple manufacturers. We have implemented many applications from conceptual design to system start-up, and we are known for providing invaluable operator and E/I training and extensive documentation before we leave your site.

The Fitch Company is not in the maintenance business. We provide necessary control system information required for plant personnel to maintain the system. Follow up support via dial-up connection is provided when further assistance is needed for plant personnel.

Projects include:

  • Jagenberg Teleset/Telebock replacements on new winders and retrofit applications. System controls automatic recipe setup, station positioning (single drum), slitter positioning, roll width — diameter — dependent nip pressure controls by controlling station pressure, rider roll pressure, and friction damper pressure. The system also provides an auto stop on windup diameter or lineal footage.
  • Operator control upgrade, including the replacement of discrete operator buttons and potentiometers with single HMI devices and necessary E-stop controls
  • Load cell installation and control system implementation in existing winder drive systems
  • Motor generator set replacement with the new digital drive system
  • Analog drive replacements
  • Stop on diameter and stop on lineal footage implementation using PLC systems

We implemented all applications using standard PLC hardware and drive equipment and left the client with thorough hardware and software documentation for clear, user-friendly maintenance.

The Fitch Company uses the machine and mechanical discipline-specific expertise provided by Lee Nelson of Thayer Brook Associates for our winder and finishing system control solutions.

Supercalender Controls

A Supercalender was experiencing increased electronic hardware failures due to age and condition. A project was proposed to replace the electronic equipment including the drives. The Fitch Company was contacted to execute this project due to past experience on similar projects and extensive experience on finishing applications (reels, supercalenders, winders, roll wrap, cut size, and sheeters). The project had a very aggressive schedule, requiring design and construction in only a four-month time period. The Fitch Company provided all field coordination, hardware specification & procurement, panel fabrication, software development, field engineering, startup and checkout for the entire project excluding the drives. A new drive system for the unwind drive, two main stack drives, and the rewind drive was provided by Rockwell Automation. The Fitch Company provided field-engineering support to creating the necessary field details for getting the drive system installed.

The Scope of this project included replacement of the following control systems:

  • NIPCO Roll Control System
  • Sensomat Control System
  • Roll Leveling / Loading / Stack Opening Control System
  • Siemens Simatic S5 / 150 PLC system including all discrete and motor control functions on the Supercalender
  • Main DC Drives (By Rockwell Automation)

NIPCO Roll Control System

The #2 Stack Supercalender includes zoned Nipco rolls on the top roll (queen roll) and the bottom roll (king roll) of the stack. These rolls include two counter zones and eight NIPCO zones. The shell of the NIPCO roll is positioned relative to the roll shaft based on the interaction of the counter zones and the NIPCO zones. These rolls have a floating shell design. Pressure control and position control is required for both NIPCO rolls. In addition, stack closure occurs with shell position control and the roll leveling pistons. The old system performed the majority of the control algorithm in the Siemens S5 -150. This was difficult for mill personnel to understand, or troubleshoot. The new control software developed by The Fitch Company resides in the ControlLogix processor utilizing standard PLC ladder and function block instructions in a very well documented manner.

Sensomat Control System

The existing Sensomat control system consisted of rack-mounted analog control boards. Adjustments to the system were made utilizing potentiometers, jumpers, and other hardwired modifications. The new system developed by Rolf Schuh and The Fitch Company was implemented utilizing standard PLC ladder, function block instructions, and Rexroth solenoid driver cards.

Roll Leveling / Loading / Stack Opening Control System

The existing Roll Leveling / Loading control system resided in rack-mounted analog control boards. Adjustments to the system were made utilizing potentiometers, jumpers, and other hardwired modifications. The new system developed by The Fitch Company was also implemented utilizing the ControlLogix PLC system.

Project Execution

The Fitch Company was the prime engineering company for this controls upgrade project. The new control system is comprised of an Allen Bradley ControlLogix PLC, with an RSView32 HMI. The Fitch Company provided all PLC / HMI software configuration for the Supercalender excluding the drive software. All control system cabinets were built and fabricated in The Fitch Company’s Rumford, Maine office. The top section of the existing operator console was replaced with new, equivalent, stainless steel panels, housing new operator devices and two HMI’s. We provided complete system documentation included interconnection diagrams, schematic diagrams, block diagrams, network diagrams, and cable/wire pulling schedules. Subcontractors were used for hydraulics (Joe Qualey of Advanced Hydraulics Inc.), and for the Sensomat replacement (Rolf Schuh of Calserv). The drive software was written and provided by Rockwell Automation. Field construction for the project was done by Cianbro Corporation, Pittsfield, Maine.

Project Result

The project was a complete success. The new system has essentially eliminated downtime caused by the controls. This new Supercalender Control System now provides the following:

The thoroughly documented system allows for easier troubleshooting.
All software is open with a nonproprietary design allowing for ease of modification.
The design utilizes standard components that can be replaced quickly and easily, minimizing downtime.
Plant personnel are familiar with the control equipment used and can maintain the system.
Logically designed and engineered, the mill can support the system instead of bringing in expensive outside help.

Automated Core Cutter Application

The Fitch Company has partnered with Berlin Foundry and Machine manufacturing Automated Core Cutter Machinery. A basic description of the operation of the equipment is as follows:

Operator programs length of parent core, length of cores to be cut and number of cores to be cut, trim cut or no trim cut, all done using Allen Bradley PanelViewPlus Operator Terminal. Parent cores are loaded into the hopper by use of forklift truck, and parent cores are then loaded onto saw by automatic core feeder. Parent core is then fed into the saw and cut to whatever length has been entered by the operator. Cut cores can then be fed into other core preperation equipment or accumulated on collection tables.

The Servo controls and other electrical control system components are developed jointly by Berlin Foundry and The Fitch Company. Generally, Allen Bradley ControlLogix L61 series processors are utilized for this application. We can provide another processor family upon request.

Dial-up technical support is provided on all installed systems thus providing cost-effective control support depth when and if necessary.

The end results of this joint venture is a mechanically sound core cutting system with a well designed and easily maintainable control system.

Contact us or Berlin Foundry and Machine for additional information.

Roll Wrapper Applications

The Fitch Company has completed a wide variety of roll wrapper projects, from basic roll wrapper pocket modifications to complete roll wrapper system installations. We work closely with client staff – mill engineers, operations and maintenance personnel — to obtain a complete understanding of project scope as well as installation and custom requirements. This hands-on approach, combined with thorough fieldwork and detailed engineering work, ensures safe and successful start-ups.

In addition to providing everything from conceptual design services to system start-up, The Fitch Company offers operator and E/I training and final hardware and software documentation, so our clients are always left with maintainable and user-friendly systems.

Typically, our projects involve software implementation of roll wrap controls on Allen-Bradley PLCs with multiple PanelView operator interfaces. We design and install separate hardwired emergency stop control systems to ensure all equipment will function properly when the stop function is used. We also obtain machine-specific knowledge necessary to implement safe and practical controls solutions.

Complete systems design services include:

  • Motor control center design
  • Power system modifications
  • Operator console design
  • Installation details
  • PLC cabinet design and fabrication
  • Wiring specifications
  • Details for building general electrical modifications

Sheeter Applications

Jagenberg Synchro Folio Controls Upgrade

A sheeter was experiencing increased electronic hardware failures due to age and condition. A project was proposed to replace the electronic equipment. The Fitch Company was contacted to execute this project due to past experience on similar projects and extensive experience on finishing applications (reels, supercalenders, winders, roll wrap, cut size, and sheeters). The first sheeter (PCP4) was completed in 1999 with the subsequent sheeter (PCP5) completed in 2003.

The Fitch Company provided all field coordination, hardware specification & procurement, panel fabrication, software development, field engineering, startup and checkout for the entire project.

The Scope of this project included replacement of the following control systems:

  • Binary Control Processor and Associated I/O
  • Automation Control Processor and Associated I/O

Binary Control System

This control system handled all discrete controls for the sheeter excluding the Marquip flying splice unwinds. The primary sections of the sheeter included high speed ribbons, knife, reject gate, transfer gate, overlap aprons (top and bottom), layboy, ream air removal system and final transfer to cartonizer.

The old system performed the majority of the control algorithm in the Siemens S5 –150. This was difficult for mill personnel to understand, or troubleshoot. The new control software developed by The Fitch Company resides in the PLC5/40 binary processor utilizing standard PLC ladder and function block instructions in a very well documented manner.

Automation Control System

This control system handled the more complex functions of the sheeter including:

  • Sheet tracking through all sheeter sections
  • High speed reject gate control
  • High speed transfer gate control
  • Automatic splice detection and rejection
  • Ream transfer control based on ream sheet count
  • Automatic unwind detection to determine how many webs are being cut
  • Ream count and production report generation ie.
  • Reams / shift, total tons per shift, tons rejected, tons trimmed.

Project Execution

The Fitch Company was the prime engineering company for this controls upgrade project.

The new control system is comprised of two Allen Bradley PLC5/40 Processors, with an RSView32 HMI. The Fitch Company provided all PLC / HMI software configuration for this sheeter controls upgrade.

All control system cabinets were built and fabricated in The Fitch Company’s Rumford, Maine office.

We provided complete system documentation included interconnection diagrams, schematic diagrams, block diagrams, network diagrams, and cable/wire pulling schedules.

Project Result

The result of the project is a complete Sheeter Control System which is:

  • Well Documented
  • Open with nonproprietary design
  • Designed and developed utilizing standard components
  • Easily maintainable by plant personnel
  • Logically designed and engineered

Since the new control system has been installed, downtime due to control system issues has been essentially eliminated. The project was a complete success.