NEW BRUNSWICK SCIENTIFIC BioFlo 4500, Manual To Operations

Page: 43 / 214

New Brunswick Scientific Co., Inc. User’s Guide
43
5
5
A
A
S
S
S
S
E
E
M
M
B
B
L
L
I
I
N
N
G
G
T
T
H
H
E
E
F
F
E
E
R
R
M
M
E
E
N
N
T
T
O
O
R
R
/
/
B
B
I
I
O
O
R
R
E
E
A
A
C
C
T
T
O
O
R
R
5.1 Baffles
The four baffles inside the vessel are removable, should the process require low
shear operation such as cell culture operations. The baffles are removed by lifting
them from the vessel with the headplate removed. They are installed in reverse
fashion.
5.2 Impellers
5.2.1 Rushton Impeller
The BioFlo 4500 is equipped with two Rushton six-blade impellers as
standard. The impellers’ position should be verified before securing the
headplate to the vessel. The impellers are adjustable along the length of
the shaft and are secured to the impeller by a locking collar.
Proper positioning of the impellers on the shaft is absolutely essential in
order to obtain optimal oxygen transfer rates (OTR).
The lower impeller should be positioned about one impeller diameter
above the bottom of the vessel (for the 20L vessel, 3.75"/9.53 cm; and
4.31"/10.95 cm for the 30L vessel).
The upper impeller should be 1 to 1½ impeller diameters (for the 20L
vessel, 3.75"-5.63"/9.53-14.30 cm and 4.31"-6.47”/10.95-16.43 cm for the
30L vessel) above the lower impeller.
(See drawing on the following
page.)
CAUTION!
On initial set-up, prior to operation, check that all impellers are
tightly fastened to the drive shaft.