Brooks Instrument Mfi Series - Manual (Page 54)

4-16
Brooks ® Mf Series
Section 4 Maintenance &
Troubleshooting
Installation and Operation Manual
X-TMF-Mfi-Mfx-MFC-eng
Part Number: 541B074AAG
August, 2009
Orifice Size (inches) Minimum Flow Rate (sccm)
32°F (0°C) 70°F (21.1°C)
0.0013 5.3 (5.7)
0.002 12.5 (13.5)
0.003 39.2 (42.2)
0.004 82.5 (88.9)
0.0055 190 (205)
0.007 374 (403)
0.010 748 (806)
0.014 1364 (1469)
0.020 2673 (2879)
0.032 6490 (6991)
0.048 12980 (13980)
0.062 22000 (2879)
0.078 31900 (34400)
0.093 42500 (45800)
0.120 69300 (74700)
0.1405 95,500 (103,000)
0.1495 108,200 (116,600)
Inlet Pressure = 10 psig
Outlet Pressure = 10 inches of water (0.4 psig) or less
Note: Flow Rate based on Nitrogen
5. I f the measured flow exceeds the value shown in Table 4-4 proceed to
step 7.
If the flow is less than expected, depressurize the controller and
disassemble the valve following Disassembly, Section 4-4 and proceed to
step 6.
Note: If the orifice size in use is unknown, it can be determined by:
Refering to Section 4-7, Orifice Sizing.Opening the control valve and
inspecting the orifice. Refer to Section 4-4, Disassembly
Consulting the factory with the full model number which is printed on the
front label of the controller and the order.
6.For orifice sizes 0.007" and greater add a 0.005" thick larger diameter
flow clearance spacer.
For orifice sizes less than 0.007" add a larger diameter 0.005" thick large
diameter flow clearance spacer and two 0.002" thick small diameter flow
clearance spacers. Refer to Figure 4-3b for spacer placement.
If this does not provide adequate flow, remove one at a time, 0.002"thick
small diameter spacers until the correct flow is achieved.
Assemble the valve following Assembly Section 4-4, utilizing the old socket
head cap screws and the 020 elastomeric O-ring. Apply inlet pressure and
zero volts to the valve.
Table 4-4 Orifice Capacities