Process and Production Control Package

Abstract

Summary When a computer control system reaches a certain size it is no longer enough that the system is possible to work with. In order to be effective the work also must be convenient. Thus one of the basic concepts in the joint Billerud/IBM efforts has been that a computer control system should conveniently be used by - process operators - production managers - system engineers and programmers. For the communication between process operators and the process control system, carefully designed process operators consoles were developed. These consoles are designed in such a way that they are convenient and effective to work with for process operators as well as for process engineers. In order to ensure a good communication between production managers and control systems the process computers have been located adjacent to production managers' offices. During the first process computer project at Billerud, the 1710-project, it was found that programming took far longer than expected. When installing a second computer, an IBM 1800, controlling not only paper-machines but also a Kamyr digester and chemical recovery processes, an effective way of programming was necessary. Thus a programming package for the basic functions of process control and production follow-up was developed. The process and production control programs (PPCP) enables the system engineer or programmer to program the entire periodic part (read, check, filter, convert, control, etc.) of the control system by filling in forms. After punching, special conversion programs select the proper data acquisition and control algorithms based on these forms. Included in the system are routines for “cold start” standard messages, contract change handling, data acquisition and data reduction (as a base for the reporting system) etc. Also, the package includes routines for the communication with process operators and process engineers. Although the system is general and applicable to any process industry there are also a few routines available, which have been developed for pulp and paper applications, e. g. programs treating the signls from a travelling basis weight and moisture meter. The PPCP package has been used extensively for the IBM 1800 process computer installed at Gruvon in 1968. The package has proved to be as effective and convenient as expected, both computerwise and in handling. Thus an improved version, compatible with a modern operating system, is now in use in two IBM 1800 process control computers at the Gruvon mill.