Modern sugar mills and iron foundries require very heavy-duty vibratory drives. Natural frequency conveyors drives are said to last at least 45.000 hours continuous work but the experience shows that this is not always happening. Drives from many imported models after one or two years started to show signs of severe deterioration.

Mavi has decided to project and build stronger and more reliable drives. First units installed are running continuously since Jan. 1999 and have proved that a sturdier drive with larger and more sophisticated vibration proof bearings as well as special sealings may help the maintenance crews concentrate on more delicate problems instead of reparing simple vibratory drives, reducing costs significantly.

Two large Brazilian foundries exporting to the USA and Europe, have their conveyors now running 24 hours a day with zero downtime since 1999. The world largest sugar mill operates two units 24 hours a day since 1998, with no replacement of any parts at all.

Special alloys have been chosen for the main drive components, like the rocker arms, the main shaft and the sealings. The 3 phase motor is a little overdimensioned, also to keep its wear limited to a reasonable standard. The use of frequency inverters to adjust the speed precisely is a must for these long lasting drives.

Mavi has recently examined the conditions of many new type installed drives and no significant sign of wear has been detected.