To equipment searchers: When you buy a new dust collector

If you buy a new dust collector, it is very recommended
to weld round plate on the hopper area for the purpose of
future flow aid.

Even if the flow is smooth at the beginning, the powder
may become finer or stickier and could be clogged at the
discharge hopper. In order to avoid this situation, just
adding round plate to be welded on the hopper is recommended.
You can hit this plate when clogging or install air knocker
later. You can find the appropriate specifications from the
air knocker details as follows.

** Exen air knocker details **
http://www.aaamachine.com/php/link.php?q=4I613lkF_ex8gXSWHQj8iKHWw