| UCB FILMS |
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| New control system for UCB Films from IEA Ltd. |
| Gx Environmental has completed the installation and commissioning of a new distributed process control system for the Viscose plant at UCN Cellophane Ltd, part of UCB Films. The previous control system for the Viscose plant had been modified several times over the years but software changes were complex. Later as plant modifications became necessary UCB had started to introduce PLCs, mainly from Mitsubishi, for local control. |
| Mark Barham, Projects Controller at UCB Cellophane, looked at various options for the replacement on the existing Ferranti Argus system which was becoming obsolete, on the Viscose section of the cellophane manufacturing process where significant plant modifications were needed. One of the requirements was that UCB Cellophane would continue to use their site standard Intellution SCADA and that there would be a higher level of in house control of such things as SCADA mimics and management reports. |
| Mark was already familiar with Mitsubishi equipment and was using FX micro and A Series modular PLCs. UCB had also been using Mitsubishi’s Melsec Medoc Plus (MM+) IEC1131-3 programming package which is compatible with the whole range of Mitsubishi PLC s. The decision was taken to install a PLC based distributed control system and the viscose plant includes some continuous process with flow, temperature and pressure loops, a PLC with process control capabilities was needed. For this UCB Cellophane chose the Mitsubishi Q Series system PLCs. Another good reason for choosing the Mitsubishi route was that it provided a cost effective solution. |
| Mark Barham recognised that the project was too large to be carried out in house and so set out to find a systems integration company with the required skills and experience. In depth investigation of every possible contender would have been too time consuming so UCB Cellophane went to Mitsubishi to discuss their Systems Integration Partners Programme and were introduced to IEA who’s team of 30 hardware and software engineers work closely with a small number of partners, notably Mitsubishi, Microsoft and Oracle Corporation. |
| Mark visited IEA’s Head office together with UCB Cellophane’s IT manager Peter Sampson, and was impressed by IEA’s facilities and the engineering team who would work on their own project. As a result UBC Cellophane placed an order for the new control system to be installed and commissioned in the September. By the time Mark visited IEA; the project had been under consideration for nearly a year. Many of the original staff members who had worked on the installation of the Ferranti system had retired or left the company so there was a significant amount of plant investigation to be done. IEA wrote the functional design specification together with Neville Lear and Graham Wood from UCB Cellophane’s project engineering team and as a result, some minor adjustments were made to the original specification. |
In simple terms, cellophane is made by processing wood pulp and additives to produce viscose. This think orange liquid id then filtered several times and de-aerated before being fed into the casting section where it becomes a film that passes through a series of baths and around 250 rollers before emerging as cellulose film. The film is processed in many different ways, for example by metallising, coating or colouring, to suit it to a wide range of uses such as self adhesive tape, food packaging, sweet wrappers and metallised film. |
| The initial installation was on one of two banks of four viscose filters with backwash systems. The installation was carried out over two days and IEA engineers stayed at UCB Cellophane throughout. There was one small glitch on the initial installation which IEA addressed by writing a monitoring system to include critical valve checks and after a week of monitoring the first bank, the control system was installed on the second bank of filters. The final stage of installation was the paddle tank control which according to Mark Barham, “went in without a fault”. The control system installed by IEA uses Mitsubishi PLC s on a high-integrity, Melsec Net 10, dual redundant fibre optic network. The capabilities of Mitsubishi’s Q Series PLC offered a variety of possible configurations for the new system. IEA and UCB decided on a floating master PLC with disturbed I/O. The Q Series was used for its process control capabilities with A Series and Q2A I/O used for a cost effective solution. |
| A 10 base 2 Ethernet connection links the Melsec Net 10 network to the Fix Intellution SCADA package and other plant information is fed into the same SCADA node via Modbus. This configuration has made the system very flexible and the system architecture means that it can be added to in many ways as Devicenet, Profibus, Modbus or Mitsubishi CClink communications cards are available so hardware from a wide range of vendors could be incorporated. The single Ethernet connection has made it possible to access the entire system and interrogate the PLCs over Melsec Net 10 using the latest upgrade to MM+ on the main SCADA node. |
| In Mark’s initial specification it was planned to use only the SCADA system for plant monitoring but IEA recommended the use of local HMIs and installed Mitsubishi E300s. Mark Barham says this was a very valuable change, “they earned their money just during the commissioning” he says. “The control room is fairly remote from the plant but with the HMIs we were able to set up local alarms, start and stop and interrogate the I/O locally.” According to Mark once people realised the capabilities of the HMIs they wanted to do more and more with them and realised that if the SCADA system should ever go down the E300s provided an additional “level of defence” as it is possible to control the system from the HMIs. IEA supplied UCB Cellophane with “very comprehensive” documentation for the project including process specification documents, handbooks and PLC code documents. UCB Cellophane has taken an ongoing support contract which is run on a unique token system constructed by IEA to suit UCB Cellophane’s needs. UCB Cellophane buy a number of ‘tokens’ which can be used for service, training or modifications to software. IEA supply a monthly statement so that UCB Cellophane can track their usage and future needs. |
| Once installation and commissioning were complete IEA requested a review meeting with everyone involved at UCB prior to system sign off. Mark Barham says “IEA were very keen for feedback but there was no adverse comment, they were very quick to respond to the project needs and during the upgrade there was virtually no disruption to the plant operation.” |
