Vol. 19
May Issue
Year 2018

Good Vibrations

in Vol. 19 - May Issue - Year 2018
Robotic Grinding Synergy With MMF

Robotic Grinding Island, with one belt in and one belt out

A grinding belt unit of latest generation with Siemens S7 PLC managing the "pressure control", combined with a Fanuc Robot 6 axis

A Robotic Grinding system for metal chairs

Centreless Grinding System, above and below

Dual motor vibratory finishing bowl, with automatic mode to manage the raising-up (2) or the going down (1) of the workpiece respect to the level of the finishing media, towards a single-axis mechanical shaft

A robot for loading and unloading a Multi Drag© Finishing System, where components have been previously belt grinded, is a typical example

The robotic grinding on metal workpieces is a widely interesting solution for at least three main reasons:
1. High ratio of productivity, based on a solution that can operate almost 24 hours a day, for 7 days a week, during the whole year, with a fast payback of the investment;
2. High repetitiveness
3. High quality of the final products

High Precision Performances

The robotic grinding systems of today offer a very high precision degree, thanks to the last generation design of "pressure control", and an additional axis added to the 6 axes of the Robot, that allow compensation of the pressure of the exposed surface of the workpiece to the contact wheel of the grinding belt.


Thanks to the DCS (Dual Check Safety) software, the Robotic system is forced to stay within a virtual perimeter, designed during the production and assembly of the robotic system itself, to assure that the robot will never go out of the imposed perimeters, thus assuring the best safety level to the whole system.
This feature is only one of the advanced safety skills offered by modern robotic grinding systems.

Centerless Grinding

The solutions offered by the modern grinding systems, are also going beyond the Robotic lines.
In fact, the centreless finishing systems are extremely performant and reliable, based on a solid experience developed by the eighties to nowadays.

The Robotic And Centerless Grinding Family

The portfolio of last generation grinding solutions is extremely wide and based on several kinds of applications on metal sheets, metal pipes, and metal components.
The automation degree of this kind of solution is extremely high and includes sophisticated knowledge of robotics.
How to combine this sophisticated world of finishing solutions with the one of MMF, where Mass Metal Finishing is mainly based on a « Mass » vision of the components handling?
When the two different worlds of Robotic belt grinding and MMF are merging with each other?
Why these two worlds are today more open to synergy?
Let’s go through the above questions in the following steps, as follows:

Historical Preface Of The Synergy Between Grinding And MMF

It is a matter of fact that belt grinding has been forever and ever « THE ESSENTIAL » finishing task before vibratory finishing.
One of the main reasons is related to die casting, where the parting line left from the conjunction of the moulds during the injection of liquid metal must be removed to leave a better geometry to the workpiece.
In fact, the isotropy of MMF tends to leave this kind of defect although the finishing process is long-lasting.
Other reasons are, among many others, the presence of areas with too high rugosity or imperfections where the belt grinding can optimize the geometry and or the rugosity in one or more steps with different grades of abrasiveness.

How To Combine Robot Grinding To MMF

To merge these two kinds of finishing technologies with a high level of automation is something easier today, mainly thanks to the wide number of solutions available like Drag Finishing, but also vibratory finishing with automatic features tending to combine the workpieces to holding frames or masks and frames.

How to combine these two kinds of finishing technologies is, in the case of Drag Finishing, a question to assure on one side, the correct rhythm of in/out of the workpieces grinded.   On the other side, to balance the in/out rhythm with the correct sequence of finishing process (i.e.: smoothing and polishing), processing times, loading/unloading time, and so on.

When The Two Different Worlds Are Merging?

As already mentioned above, the world of die casting is certainly one major element requiring the grinding prior to obtaining a homogeneous surface finishing towards MMF.
Another field might be lost wax casting, or laser cutting and some other manufacturing methods leaving relevant burrs, irregular appendix and similar imperfections.
Today’s opportunity, moreover, to get dry mode vibratory finishing of such kind of components, in some situations, make the option of getting an ISO 14000 finishing system as an added value to invest in a robotic finishing or Industry 4.0 finishing system.

Why These Two Worlds Are Today More Open To Synergy?

Robotics is becoming more and more an element joining not only the different tasks of fabrication or finishing, but also the way to see the evolution of Man in his professional environment.
Whereas in the seventies, a young worker was stimulated to specialize in hand finishing (like belt grinding or hand polishing), and a vibratory finishing unit was mainly operated by an operator with much less automation, in the third millennium, a young engineer is more easily stimulated to specialize in writing programs of a robotic finishing system.
In the Japanese culture, the man is generally involved in the most critical steps of the fabrication workflow.
This way of acting has generated efficiency and has involved operators and specialists in strategic areas of the production, thus offering an evolution respective to the past implementation in « mechanical » operations.
From the point of view of safety and health, the evolution of the norms, for example in ergonomics, are tending to reduce strengths and repetition of heavy operations, to advantage better efficiency.
Collaborative robots are helping line operators more and more to do better, faster and in mostly safe ways, various kinds of operations.
This is mostly why the two worlds are today more open to synergy.

Author: Paolo Redaelli
Good Vibrations
by Paolo Redaelli
Contributing Editor MFN and
Rollwasch® Italiana S.p.a.
Tel. +39.0362.930 334
Fax +39.0362.931 440
E-mail: paolo@mfn.li