Rißprüfung zerstörungsfreie Werkstoffprüfung / Rissprüfung

Modern techniques nowadays enable production of  large numbers of parts within short periods of time. Up  to now, modern material testing was not in a position to  keep pace with such short time intervals.

The  development of the eddyliner®P enabled extremely  high test rates. In the present case, the problem was to design mechanical handling so that test results could be transformed into sorting actions without reducing speed.  For testing of balls, ibg has solved this problem, ie. application of PMFT at high test speed, mechanical handling, separation and reliable sorting of balls is  possible within extremely short periods of time.
Test task

A  renowned manufacturer of balls, KGM Kugelfabrik Gebauer  at Fulda, has been testing balls for material mix with  mono-

frequent instruments for many years. In the past it occurred several times that "bad" balls were not detected with the mono-frequent instruments. ibg was appointed to supply a reliable solution.

 The  conditions were as follows:

• Compulsatory use of Preventive Multi-Frequency  Testing
• Highest-possible test rate (minimum 36.000  balls/hour)
• Highest-possible reliability to detect all  possible material mix-ups
• Sort system suitable for broad range of dimensions: 1.5mm - 6mm in diameter

The  sort system eddysort®K as shown on the photos  (following pages) met all these  requirements!

Course of ball testing

The  balls are separated and led to the probe via sloped indexing disk equipped with "bags" to pick-up the individual balls. Change-over to different ball  diameters only requires exchange of indexing  disk.

A  bunker preceding to the indexing disk has a storage  capacity of 250m³of balls. In case of lack of parts,  further balls will be refilled automatically from the main bunker. The indexing disk is turned at constant  speed by dc motor. On their way to the test position, the balls inside the "bags" move the balls inside the bunker to avoid "bridging". Testing is triggered synchronously by a rated shift register. A proximity  switch ensures that testing is only triggered with a  ball available.

After testing the balls reach a sorter, whose  position depends on the sort decision made before. The  balls are

passed on to a sorting channel and to the  relevant containers via flexible tubes. Damage of balls  is avoided by most careful handling during testing for  material mix and hardness using Preventive  Multi-Frequency Testing (PMFT) eddyliner®P frequencies from 800Hz to 80kHz probe 40.000 balls/hour diameter of balls between 1.5mm and  6mm

Conveyor disk, bunker, sorting “tongue”, sorting channels