A new IT system to check twenty-four hours a day all parameters and data of the entire manufacturing chain, from raw materials to finished products, is finally available for paper mills. An effective and error-proof tool for paper mill workers.
IT has conquered paper mills, in that it has gathered, structured and managed the entire information flow necessary to keep the various steps of the manufacturing process under control. The whole set of data referring to the manufacturing process can thus help univocally identify every single step of the manufacturing process from raw materials to finished products, up to the final user.
The use of specific software now provides for a more ordered and systematic collection of information. This proposal has been put forward by a software -house from Maiolati Spontini (Ancona), Next, which implemented its own Improve System at the Sca hygiene products Lucca plant.
How does the platform work?
Improve is an example of a Mes (Manufacturing execution system) platform for the integrated management of the data obtained from manufacturing processes. Mes platforms communicate with Enterprise Resource Planning systems (Erp) and Programmable Logic Controllers (Plc), which in turn communicate with the machines they receive all the data from. The entire enterprise communication is through ethernet, i.e. the company network. According to Next project manager Nicola Bergantino, «this platform provides, on the one hand, for a direct interface with machines through the ethernet, as it detects the data on sensors, measurements and machine status through specific protocols; on the other hand, it provides for interaction with Erp systems by getting information on production. Interaction with the machines used and the entire smart logic of the system occurs through an agent-based architecture, i.e. a software application methodology which is very innovative that is still little in the industrial sector. System extensions in terms of new interfaces and integration of new algorithms are very easy to perform and facilitated by the architecture used, with any new integration being an agent, i.e. a new software entity entering the system».
Another feature of the Improve system lies in the fact that it is an open and dynamic system, capable of evolving over time to meet the plant needs. This way, applications can be improved and enhanced based on the needs of the paper mill.
Sca felt the need to set a structured monitoring activity of the entire process, starting from paper manufacturing to product traceability, including the converting and warehousing departments up to the shipping department, with the objective of generating a flow of data allowing to trace the individual steps of the manufacturing process of each bench, coil or individual product, also in relation with the raw materials used, like cellulose and chemicals.
«Paper mills are complex systems where hundreds of interrelated variables need to be considered», says Valeria Guzzardi, who works as process expert at the Altopascio plant. «This complexity brings about the need to keep all process parameters clearly under control and relate them one to the other by means of a single tool, which enables to manage them all». The system thus constantly monitors the production cycle and derives a series of data from it; it then groups the information together and summarizes it in specific or standard graphics and check cards. «Any variation in the parameters, e.g. in the installation settings or the measurements carried out, ought to be easily analysed and monitored». The choice by Improve was based on principles of intuitiveness and ease of use. «The Improve platform has to be managed both by paper mill workers and managers; therefore it had to be developed in such a way, so as to easily and conveniently meet the needs and the technical language requirements of both parties. We have basically looked for a tool that could facilitate our work inside the paper mill».
Detecting and acting
Reading the parameters obtained provides with useful indications, which will be helpful for the paper mill both in the short run, as it will enable it to immediately put in place possible corrective measures, and in the medium and long run to plan strategic actions for process improvement.
«The system is basically a data collector: in the first step process parameters are collected and installations are set both automatically directly through the paper mill Dcs (distributed control system), and manually by the paper mill staff; the second step consists in data analysis: data is compared and relations are established to then draw the conclusions necessary to carry out operations on the installation, e.g. to improve a product or its efficiency or understand the reason for a breakdown. If during data collection a parameter exceeds its usual range, this can be immediately detected, so as to enable the paper mill staff to promptly intervene. It is furthermore possible to carry out a more far-reaching analysis covering several months of the trend of a given variable. Values are namely stored forever, also in case of unintentional closure of the data sheet». The system is therefore capable of monitoring the manufacturing system 24/7.
The various steps in the paper mill
The first step carried out in the paper mill consisted in the entering of all data that up to that moment had been collected separately; this massive and long work implied the migration of about 5,300 variables. «Before installing Improve we used to use simple excel tools, where database information was entered manually». Besides posing risks of error when entering the data or forgetting to enter them, the old method did not allow highlighting possible overshooting of the range in real time and did not therefore make it possible to act immediately. Furthermore, it did not provide for the possibility of working simultaneously on the database, which is fundamental. «The new system, instead, provides several operators to work at the same time, with browser access through any device by means of passwords: this way the values entered are available to all those working on the process».
Once data was transferred, it was then necessary to modify the passwords of the system based on the new needs emerged during system implementation. The paper mill personnel were then trained and the programme was subsequently tested on the field. According to Mr. Guzzardi, «paper mill technicians have rapidly become accustomed with the new system and have soon proved to be very satisfied with it, both because much data was automatically entered, thereby making data collection much quicker, and because the system provides for a very impactful visual check, whereby it is easier to identify values outside the centre line or close or exceeding limits». The system is currently used in the entire paper mill, from the preparation of the paste to the paper rewinder.
The system makes it possible to monitor the entire system. As such, it meets the paper mill need to keep energy and raw materials consumption constantly under control, thereby enabling technicians to be more autonomous and involved that usual and act in a more targeted way.
It is currently being considered to completely extend the project also to the management of finished products, i.e. the converting sector, where a system for just in time supply management (kanban) of working lines has been implemented.
In the meantime, Next continues working and studying new applications of the software system for other plants of the Swedish multinational.
Next is a software-house from the Marche region, which produces and markets software systems for process monitoring and data management. The company can profit by the twenty-year long experience of a team of IT experts and also collaborates with the local Polytechnic (Università Politecnica delle Marche), as well as with major industrial groups from several sectors for defect diagnosis projects in complex systems and energy efficiency smart control systems.
The Improve System software has been ad hoc designed for the industrial sector. It provides for the monitoring of the efficiency of manufacturing plants, as well as process and quality statistical control, warehouse management and systems for just in time supply (kanban) e defect diagnosis in complex systems.