TRENKER ABRASIVE PLANT TECHNOLOGY reaches for new dimensions with a new series of electro-plating plants for the manufacturing of large-size heavy diamond and CBN electro-plated peripheral and profile grinding wheels with dimensions of up to max. 700 mm diameter and a weight of up to 300 kg.
The plants are characterized by their innovative handling concept for the grinding wheel blank by means of a swivelling and rotation unit as well as the user-friendly adjustment of the function parameters by a touch-screen operators’ terminal.
Machining with diamond or CBN electro-plated grinding wheels has attained a more and more important role in the last years, as it allows to achieve high-precision shaping and surface finishing of many different materials in a few working operations. Here, the cutting speed as well as the dimensions of the work pieces have increased considerably. This implies the need for the use, and therefore the manufacturing, of larger grinding wheels. Furthermore, the new plant technology opens up new applications for large-scale grinding wheels, which up to now were not sufficiently available for lack of adequate production means. With the newly-developed plant technology of the DBA 1-508/608/708 series, mass production of large-size diamond or CBN electro-plated peripheral and profile grinding wheels is possible in a rational, reproduceable and efficient manner.
Swivelling and rotation unit:
The innovative crucial part of the plant and the process is the swivelling and rotation unit, with which the problem of handling large and heavy grinding wheels in an electro-plating bath was solved for the first time. The swivelling and rotation unit permits the movement of the grinding wheel in horizontal and vertical direction for positioning in the electro-plating tub and for mounting or removal. Besides that it allows to swivel the grinding wheel during diamond tack-down in such a way that the surface area to be coated at a time is always kept in a horizontal position and the best possible grits distribution – even on profile grinding wheels with complicated profiles – can be achieved. 
Due to the adjustability of the different operating modes during the electro-plating process, different diamond plating methods may be used. For this purpose, a rotation drive is integrated into the unit, which allows continuous or step-by-step turning of the grinding wheel during electro-plating.
The electric connection is made by a sliding contact on the rotation shaft and thus a permanent rotation of the grinding wheel during the coating process is assured
Touch screen operators’ terminal:
Adjustment of the function parameters necessary for electro-plating and for the process control is done centrally from a swivelling touch screen operators’ terminal, which allows the operator to control the process from the position most suitable to him. The individual control surfaces, which contain only the relevant operational elements and displays for each function mode, are selected with just a light touch on the screen. The different function parameters such as e.g. coating times, plating current, leak current, rotation intervals etc. may be input directly from the touch screen to the PLC control with Microcontroller or copied from a Laptop or the Intranet using the RS232 interface.
In the same way, the motion in horizontal and vertical direction, swivelling and continuous or step-by-step rotation of the grinding wheel, as well as the electrolyte level in the electro-plating tub and the function of the rinsing pumps, are controlled with clearly structured, easy to operate and functionally adapted control surfaces. Furthermore, the touch screen terminal allows factory programming of customer-specific control surfaces and if necessary, special functions.
Process monitoring and safety:
The process control and regulation unit continuously monitors the properties of
the electro-plating bath and thus guarantees constant and reproduceable conditions for the electro-plating process. This is carried out through continuous circulation and filtering of the electrolyte and through permanent measurement of temperature, pH value, consumption of additives and bath level. Temperature is regulated by control of the heaters according to programmed temperature-time curves, the additives are added to the bath automatically depending on consumption and measurement values and evaporation
losses are equalized by automatic addition of water. The completely electro-plated wheels are rinsed in the three-cascade standing sink (KSP). The occurring rinsing water is then used for compensation of the evaporation losses as described above. The bath chemicals being present are thus returned to the electrolyte; the balance of the electrolyte remains equal and the consumption of chemicals is minimized.
For the different function states during the electro-plating the electrolyte level may be raised or lowered accordingly. For maintenance or cleaning purposes the electrolyte may be completely transferred to the so-called electrolyte storage tank. Furthermore, acoustic and visual warning signals for the end of electro-plating time, change of filter, filling level monitoring of the additives and deionized water generation
are installed.
Conclusion:
With this new and innovative technology, interesting perspectives open up for the mass production and application of large-size diamond and CBN grinding wheels.
Currently the electro-plating plant is offered in three variations with a maximum grinding wheel outer diameter of 500, 600 and 700 mm.
makes possible energy savings of up to 75% !