Dametric

Overview

The GMS is Dametric's new generation of measuring and monitoring system for the control of the grinding process of pulp industry refiners. This outstanding system guarantees constant quality in production through the measurement, monitoring and controlling of plate gaps. Consequently, it further enhances overall performance by ensuring that processes will remain within the correct operational limits.

The system consists of both electronic hardware and software modules that are installed on a touch panel industrial PC. It encompasses an operator user interface (used for both operation and maintenance) that is highly user friendly and has a ‘help on demand’ function to clarify any issues the operator might have.

There are a number of significant advantages as compared to the old RMS system. Firstly, the installation and setup time has been greatly reduced due to the need for less cables in the system. Secondly, a large amount of the signals are now sent and received over a computer automation system instead of the old wired signals. Furthermore, the calibration of the Disc Clearance sensor (TDC) is managed with a sequence driven wizard containing highly user friendly instructions. Finally, the system stores process data in a database that can be easily evaluated in an analyzing program.

The current supported refiner types are Single Disc and Double Disc refiners. The Conical Disc refiner type is currently under development.

Hardware

The hardware modules have functions for a number of different measuring areas. These include disc gap, disc temperature, refiner vibration, touch vibration, oil temperatures, hydraulic pressures, rotor position and motor power. The CAN protocol is used as the communication protocol both between the hardware modules and between the PC software and the hardware modules.

PC Software

The PC software modules use the .NET Framework from Microsoft and they use several of the Framework's features, including the .NET Remoting and the SQL connection.

The GMS system consists of two main software applications, the DMS and the GMC.

DMS

The DMS (Data Management Service) module represents the core of the system acting as the interface towards the hardware modules. The main task of the DMS is to retrieve various parameters (for example signals and alarms) from the hardware modules and then, by using .NET Remoting, to provide them to the GMC module. It should be emphasized that it is the only module in the system that has access to the database, which stores system parameters, event log and selected parameters for the analysis of processes and faults. Furthermore, it connects to an OPC server to exchange various parameters with an operating and control system called the RCS.

GMC

The GMC (GMS Monitor and Control) is the monitoring and control GUI (Graphical User Interface) displaying different signals, alarms and the process status. This has several built-in functions designed to control the grinding process, such as the Disc Gap Controller which regulates the disc gap against a defined Setpoint. By sending control commands to the stepping motor hardware module, it is able to both increase and decrease the disc gap and consequently ensure a constant plate gap. Both the internal process parameters and the hardware module settings are accessed through the GMC. The sensors in the system need to be calibrated which is also achieved from within the GMC. The system has a safety function preventing the grinding discs from crashing.

Screenshots from the GMC: