2. INSTALLATION
Page 25
© 2004-2007 DH Instruments, a Fluke Company
2.5.2
MAKING AND BREAKING PROCEDURE FOR MOLBLOC-S
ISO-KF VACUUM FLANGE CONNECTION
n
Place the over-pressure ring past
one of the ISO-KF flanges to be
mated.
o
Place the centering ring into the
groove of the ISO-KF flange on the
outlet of the molbloc-S.
Align the mating flange against
molbloc’s ISO-KF flange, and close
the gap by hand.
Hold the flanges together and move
the overpressure ring directly over
the mated flanges.
Figure 20.
ISO-KF Style Flange
Place the clamp around the mated flanges. Swing the clamp closed. If necessary
loosen the thumbscrew to allow the thrust washer and wing nut to fall into position
on top of the clamp. Fully tighten the wing nut by hand.
To break the fitting, hold the molbloc-S with your hand and loosen the wing
nut until the clamp can be separated. Remove the clamp, centering ring,
and overpressure ring.
Never use wrenches to hold the molbloc-S body or tighten the wing nut.
2.5.2.1
MOLSTIC-S USE WITH DUT UPSTREAM
During operation the molbloc-S exhaust sound pressure can become quite high.
If desired, the outlet of the molbloc-S can be connected to exhaust plumbing in
order to dampen this noise. In this case care should be exercised to minimize
the amount of back pressure that is applied to the molbloc-S. Utilize plumbing
that is as short as practical, and with a diameter as large as practical.
In order to maximize each molbloc-S element’s usable range, the application of a
vacuum source on the downstream connection of the molbloc-S may be utilized.
Use of the Downstream Tee Assembly, P/N 401884, will facilitate this connection.
2.5.2.2
MOLSTIC-S USE WITH DUT DOWNSTREAM
DUTs that have built in flow control capability, such as MFCs, (and are to be
tested in flow control mode) must be tested in the upstream location.
Install this type of DUT upstream of the molbloc-S only.