Parr Instrument A1120HC10 - Manual

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A1120HC10 Magnetic Drive
Operating Instruction Manual
656M
Description
The A1120HC10 magnetic stirrer consists of a internal
rotor assembly with an inner set of magnets and an
outer coupling assembly with a second set of mag-
nets. This assembly is intended for medium viscosity
applications and has a torque rating of 16 in-lbs (1.8
Nm).
The A1120HC10 magnetic stirrer can be used with
both the standard stirrer shaft and impeller(s) or
with a gas entrainment stirrer arrangement. It is
designed to stir at speeds up to approximately 2000
rpm. Maximum stirrer speeds are dependent upon
the viscosity of the vessel contents and the resultant
load on the motor.
This magnetic stirrer requires minimal maintenance;
however, it is important to protect these magnetic
stirrers from the heat in the reactor vessel. To pre-
vent overheating each magnetic drive includes a
cooling sleeve. The cooling sleeve is held in place
on the housing with a snap ring and seals against
the housing with two O-rings. A steady fl ow of cold
water through this sleeve during all vessel operation
at temperatures above 80 ºC is required. Excessive
heating without use of the cooling water will also
damage the O-rings in the cooling sleeve.
Shaft Removal and Installation
To remove the stirrer shaft hold the A1147HC outer
housing of the magnetic drive assembly, and un-
screw the stirrer shaft in a counter-clockwise rotation.
To install a replacement or alternate shaft, hold the
outer housing of the magnetic drive fi rmly and screw
in the new shaft.
*Note: It is important to hold the housing
securely when installing any of the stirrer
shafts so that the threads are fully engaged.
Magnetic Drive Maintenance
All rotating parts in Parr magnetic drives are self
lubricating and do not require servicing during nor-
mal opera tions. It is advisable, however, to check the
drive from time to time for any evidence of leakage
into the con fi ned space between the inner and outer
rotors. This can be done without removing the drive
from the vessel head and does not require complete
disas sembly. To inspect the drive:
1. Remove the four socket head screws located near
the top of the outer housing and remove the top
cover from the housing. This will expose the plug
which aligns the inner rotor and carries the prin-
ciple O-ring seal.
2. Unscrew the 1136HC2 plug, using a 264AC5 face
spanner inserted into the two holes at the top
of the plug while holding the rotor fi rmly with
a 264AC4 pin spanner inserted into one of the
holes at the bottom of the assembly above the
cooling sleeve. With the plug removed, the sleeve
bushing and thrust washer at the top of the rotor
will be exposed.
3. Check for any evidence of leakage past the O-ring
seal. If vapors from the reactor have produced
solid deposits in or around the rotor housing, the
deposits will have to be removed to keep them
from destroying the bushings or jamming the
rotor. If cleaning is not re quired, replace the plug
and close the drive.
4. If cleaning is required, the A1125HC inner ro tor
can be removed without removing the entire
drive from the bomb head. To remove: Unscrew
and remove the stir rer shaft from the underside
of the ves sel head. Then push the rotor upward
and out of the housing using the stirrer shaft
or other suitable rod inserted through the shaft
opening.
The inner rotor is a laser-welded, sealed unit which
should require no mainte nance, but it can be dam-
aged by over heating as mentioned earlier.