Varisco S.p.A.
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5. Extract the drive housing slowly, making sure not to damage the seals inside (see picture B).
6. Remove the separating ring (05), the mobile part of the seal (06) and the fixed part (07).
WARNING: In bearings-mounted pumps as in the picture above, before inserting the hollow shaft
(08) in the hollow shaft, make sure the grub screw slot on the motor shaft coincides with the
threaded hole (01) in the hollow shaft; then, the mechanic seal will be correctly positioned.
Otherwise, push the propeller shaft until the slot coincides with the threaded hole of the hollow
shaft grub screw.
9.4.2.2.1.4 RE-ASSEMBLY
1. Check the condition of the seal faces (as well as the O’Rings in some types of seal).
2. Check the condition of the hollow shaft.
3. Clean the hollow shaft, the gland (04) (see picture above) and all involved parts.
4. Clean and oil the motor shaft (Rust jams the shafts coupling, thus increasing the danger of
damage during disassembly).
5. Wet with glycerine the hollow shaft on the involved area to ease the insertion of the
mechanic seal.
6. Carefully clean the seal faces and the separating ring before assembly.
7. Perform the steps described in Chap. 9.5.2.2.2.1 backwards.
WARNING: During re-assembly it is necessary to distribute the pressure uniformly on the fixed
ring, to prevent malfunctioning or failures.
9.5 MOTORS
9.5.1 USEFUL INFORMATION
9.5.1.1 TYPE OF SERVICE (SEC. IEC 34-1)
1. CONTINUOUS
SERVICE
Operation with constant load of sufficient duration to achieve thermal equilibrium.
2. TEMPORARY
SERVICE
Operation with constant load of duration not sufficient to achieve thermal equilibrium,
followed by a standoff long enough to restore the ambient temperature in the motor.
3. INTERMITTENT-PERIODIC SERVICE
Operation with identical cycles, each one including constant load operationg and a standoff.
The motor warming is not significant.
9.5.1.2 WORKING CONDITIONS
In compliance with IEC 34-1, the motors can work under the following working conditions.
