by Thomas Vaught » Fri Oct 28, 2005 9:59 pm
A SF 1200 cfm bench only used three orifices:
200, 400, 600. By combining the 600 orifice plus the 200 orifice you got 800 cfm. Same deal with the 400 orifice and the 600 orifice equaling 1000 cfm, etc. You wind up with 6 ranges.
On a bench I use at Ford, I had a 4th hole (which was a 100 cfm orifice) put into the SF plate. This allowed me to select flow in 100 cfm
increments, (from 100 cfm to 1300 cfm).
You can do the same with a smaller capacity bench by a 50, 100, 200, 300 cfm orifice hole combination. This would allow even finer settings (50 cfm changes) up to 650 cfm. A
8 motor bench using the 115923 Ametek motors
will flow that much cfm.
I use a 24" by 24" fixed orifice plate so there is a lot of room between each orifice therefore minimal cross talk to affect cd numbers.
Food for thought.
Tom V.