in Vol. 14 - January Issue - Year 2013
Old grey-green machine
New colors for new cleaner production environments
View into the control unit
Control panel with operator dongle authentication
Complex plc control with video surveillance on an android tablet system
Ten years ago, surface finishing installations often had the image of loud, ugly and dirty plants. In many companies that were using these techniques of deburring and polishing, these machines had been banished to the most hidden places at the production site. And that was not infrequently the cellar or another place where a visitor or a customer would seldom take a closer look . In most cases, the color of the mass finishing machines was green, which has often changed to black and a muddy grey with little green paint dots.
In the last years, surface finishing has seen many improvements not only in the sector of mechanical construction, but especially in the sector of process security and electronic functions. The demands on quality and cleanliness have risen significantly. The development to brighter colors or white paintings for extremely clean production environments is reflecting this, too. In the same way, automation in production has become a steady trend in the last decade. So many surface finishing installations sold today are fully automatic interlinked systems of part feeding modules: washing, treatment and drying modules; and discharge modules. These modules are working together as independent machines with a central electronic control programmed to achieve the aim of perfect parts finishing.
A defined process consisting of many parameters has to be installed on such a complex machine. A core of that process is surely the actual slide grinding process itself in the treatment unit. Here, a certain mixture of polishing media, grindstones, chemical compounds and customer parts are mechanically and partly chemically interacting with each other to achieve the respective surface finishing. Parameters of working time, different treatment phases, motor intensities, additive dosing and much more have to be programmed. But for total automation, the secure parts flow and batch purity are new and decisive challenges.
Always connected to the topic of automation is the security aspect. The safety of human operators has top priority. Here many international ISO and EN standards as well as special customer factory regulations have to be observed. That is often not an easy task to cope with the huge amount of information, which has to be sighted before the planning and construction phase of such an installation has begun. In some customer factory regulations, even single purchasing components are mentioned. Also the integration method of these components is prescribed.
In some cases, there are strict regulations for the programming. That means that the operating concept, the realization, the program structure and even the program commenting and declaration of program variables within the source code are prescribed. Not a single detail is missed in these regulations of large corporations.
For the customer, that has of course many advantages. His employees have no need to be trained on a new external control concept. Job circulation at the customer facility is much more easily possible and maintenance costs are sinking. The rising maintenance ability of own employee personnel leads to more flexibility and a better availability of production capital.
Sensors within different parts of the installation are a kind of nervous system of the plant. Optical, weight and temperature sensors are providing steering information for batch sizes, chip re-dosing, process fluid control, parts loading and unloading, and many more critical steps. Even personal access to the sound-absorbing cabin is controlled by door sensors, which react when the doors open. Inside, the cabin control of the plant is made possible by a special mobile remote pad. A peculiar deadman control function button on that pad enables the operation of the machine within the critical security barrier for testing and maintenance purposes.
Machines with a broad spectrum of electronic intelligence often also provide the possibility to store production data. So errors and batch protocols could be transferred to centralized manufacturing systems for later analyzing and to initiate quality learning processes.
In 2012, a video surveillance system of a vibratory finishing installation was for the first time connected to an android tablet fixed on the electrical control unit. The video stream of the machine could nevertheless also be watched on any PC in the company, given the necessary rights. Even video remote assistance by the manufacturer is possible here.
Rights management is usually important for larger finishing lines. Here, machine operators can be equipped with personalized dongles. With these chips, personnel can log into the control unit and every employee sees only the tasks and reports he is allowed to use.
The more intelligent a surface machine is, the more options to maintain a high quality production there are available. Reproducibility of results and process stability are central aspects on this road to the new world of smart and even smarter machines.
by Mathieu Geuting
Spaleck Oberflächentechnik GmbH & Co. KG, Germany
Tel. +49.2871.9500 14
Fax +49.2871.9500 95