A few years ago we successfully completed an ambitious project which involved the commissioning of a control system for a lactose powder production plant that manufactures baby food. The customer, who was satisfied with the reliably functioning system, then decided to commission us with the modernization of the rest of the plant, whereby the production had to be stopped for a short time. This time the goal was to completely modernize the CIP washing station, the tanks and transporters for whey protein concentrate and the machines used for its production. Time played a key role in this project. The project was to be implemented in a German lactose production plant, in which the devices work almost non-stop. The system changeover needed to be carried out in just 12 hours in order to completely minimize downtimes of the system. A lot of work and the limited time to perform it meant a high risk of errors, which is why an action plan and good resource preparation was essential.
Up to 17 specialists worked on the implementation of the project - nine of them directly at the client’s plant.
The plant had many installations that operate on controls of various standards developed by other companies, which was due to earlier multi-stage extensions of the plant. The facilities were corroded and outdated and unsuitable for further operations.
The main task was to standardize and unify the system (including the controllers, visualization) to make it easier to operate. The integration of devices based on several controllers, e. g. the CIP washing station, was then carried out. After the modernization, it consisted of 7 lines that are used not only for washing but also for storing chemicals. The whole was then integrated into 3 tank farms (each with several tanks). In addition, the automatic system for the existing CIP station and the cleaning program for the station was modernized. However, the reduction in the number of controls required to rebuild the Profibus network and to switch the circuits to new PLCs, which offered additional space for a possible backup. Most modernized installations have been integrated into existing controls, which leads to optimization of customer costs and easy operation by the employees. Our programmers have developed a system based on Siemens and Wonderware components. The S7-400 PLC controllers improve the company's performance thanks to their high operational reliability. The Wonderware System Platform in turn introduces a uniform visualization system and enables central administration.
After completing the work, the customer received full technical documentation of the modernized facilities and a coherent management program. Schulz Infoprod is in charge of the maintenance of the delivered and modernized automatic devices.
In contrast to the standard process, where the new system is partially tested at the company, and technological commissioning as well as the final tests are carried out on-site, which can take several days to many weeks depending on the size of the system, a simulation system was developed in this case that precisely reflected the actual behavior of the system. It was then tested at the client’s plant together with the target system support for over 3 weeks, without disrupting the ongoing production. This made it possible to minimize the downtime of the system to approx. 12 hours instead of the 2 weeks that were suggested for the conventional commissioning mode! The operators had the opportunity to learn how to use the new system in practice and, had also their say about the solutions used in it. In fact, many of their suggestions were implemented during the tests. In order to support the commissioning of the system after switching the switchover, a group of 9 programmers stayed in the factory for several days, where they worked in a 3-shift mode.
The risk taken paid off and the task was completed within the assumed time of 12 hours. The client's thanks and acknowledgement for the efficiency and speed of our specialists is our greatest reward. As a consequence of the satisfaction with the modernization that was carried out so efficiently we are now being offered other projects to be carried out, not only at the Nordhackstedt plant, but also at other DMK group plants. We have gained valuable experience that we can soon make good use of.