7
3.0 System Overview
3.3 SF-1020i Description
Air flows through the SF-1020i flowbench and vents out the back of the cabinet. The test device (whatever
it is being tested) is mounted on top of the cabinet over the baseplate opening.
A test pressure meter (pressure transducer) measures the pressure or vacuum at the base of the test
device (just under the baseplate). Test pressure is the differential pressure as measured between
atmosphere and a point just under the baseplate of the flow bench. This is essentially the total pressure
drop across whatever is being tested or bolted to the flow bench. The test pressure is set by the control
system to a standard value, for instance, 25.0" (60.0 cm) of water. The flow meter (another pressure
transducer) measures the pressure difference across an adjustable flow orifice inside the flowbench. The
amount of flow is measured in cubic feet per minute (cfm).
By selecting different ranges, the flow meter can maintain high accuracy over a wide range of flows. The
SF-1020i has ten unique flow ranges, this insures the highest accuracy flow measurements from near 0 to
1000 cfm (0 to 470 lps).
3.3.1 Baseplate
The SF-1020i flowbench baseplate is 21 inches in
diameter with a 5-inch diameter airflow orifice in the
middle. Four ¼-20 threaded bolt holes spaced 5
inches apart in a square pattern around the airflow
orifice secure the test device to the plate. Adapters
are available from SuperFlow for mounting a wide
variety of cylinder heads and other test devices.
For safety, cover the baseplate opening when the
flowbench is not in use to prevent debris from
falling inside.
NOTICE
3.3.2 Test Orifice Plate
The test orifice that was supplied with your bench
is a test load. The 7-inch (17.8-cm) square plate
supplied with the flowbench has punched holes
(not bored); one is 1.875 inches in diameter, and
the other is 0.313 inches. Each plate is labeled with
the actual flow number in both intake and exhaust
mode as verified at the SuperFlow factory. The test
plate can be flowed to confirm that the bench is
working properly.
Figure 3.1: SF-1020i Baseplate
Figure 3.2: Test Orifice Plate
