MDX [en-US]
21
Oil operating temperatures for GIW bearing assemblies will
depend on pump size, speed and ambient conditions.
Under typical conditions, they will run from 50 °C – 85 °C
(125 °F – 185°F). For oil temperatures above 85 °C (185
°F) or for severe load conditions, a high quality synthetic
lubricant (such as GIW Blue) should be used. At higher
speeds, or in hotter ambient conditions, temperatures can
rise to 100 °C (210 °F). Slightly higher temperatures may
be seen for a brief period during the breaking in of new
bearings. The unit should be shut down immediately if
temperatures rise to 120 °C (250 °F).
Do not overfill the bearing assembly. The capacities listed
are approximate. When filling the bearing housing, the oil
level must be at the centerline of the oil level sight glass
when the shaft is not turning. This is the ”cold level” and
will change as the pump runs and the oil becomes
suspended in the bearings.
The oil should be initially drained after 50 to 100 hours
operation. Before refilling, the bearings should be flushed
by filling the bearing housing with a lightweight oil, turning
the pump shaft several rotations, and then draining. This
should be repeated until the flushed oil appears clean.
Bearing assemblies for use underwater should be
completely filled with oil and slightly pressurized by an oil
recirculation and filtering system. As a result, their
capacities will be several times greater than shown above
and a thinner oil will be required. Depending upon the water
temperature at the location at which the pumps are
operating, the ISO viscosity grade should be altered as
follows for mineral oil-based lubricants. See Section 6.5 for
more details on Underwater Pump Operation.
Bearing Assembly
Approximate Oil
Capacity (liter)
2-7/16
2-15/16
1
3-15/16 2
4-7/16 3
5-7/16 5
5-7/16 (PB)
1.5
1
Drive Side
Pump Side
6-7/16 9
6-7/16 (PB)
2.5
1.5
Drive Side
Pump Side
7-3/16 9
7-3/16 (PB)
2.5
1.5
Drive Side
Pump Side
9 18
9 (PB)
3
2
Drive Side
Pump Side
10-1/4 34
11-1/2 34
Water Temperature
ISO Viscosity
Grade
0 °C – 20 °C (32 °F – 70 °F)
100
20 °C – 30 °C (70 °F – 85 °F)
150
> 30 °C (> 85 °F)
200
GIW Blue oil may be used for all the above
temperatures
6.1.2
Shaft Seal Commissioning
Mechanical Seals
CAUTION
Mechanical seals require safety checks prior to start-up such as removing seal assembly fixtures, checking axial
alignment, checking torques etc. Refer to the mechanical seal operating manual for all required safety checks.
Mechanical seals are precision devices which require special care for their proper operation. The instruction manual
for the seal should be consulted for special storage, start-up, and maintenance requirements.
If the pump is equipped with a deaeration chamber (HVF), the mechanical seal must be of the double faced type with
barrier fluid. This will prevent dry running and seal face destruction.
Stuffing Box Commissioning
Prior to commissioning, the gland packing supplied with the pump must be adjusted. Preformed packing rings sets from
GIW / KSB are recommended. For alternate brands, refer to packing manufacturer’s instructions regarding installation
and use.
For gland flush supply, use suitable non-aggressive clean water not liable to form deposits and not containing
suspended solids. Hardness should average 5 with a pH>8. It should be conditioned and neutral with regards to
mechanical corrosion.
An Inlet Temperature of 10 °C – 30 °C (50 °F – 85 °F) should produce a maximum Outlet Temperature 45 °C (115 °F)
when the gland is properly adjusted.
6.1.3
Checking the Direction of Rotation
CAUTION
If motive power is applied to the pump, and it is run in the wrong direction of rotation, even momentarily, the
impeller may unscrew causing extensive damage to the entire unit. This is especially important during initial
start-up as the impeller may not be fully torqued onto the pump shaft.
The impeller must rotate in the correct direction of rotation. This must be verified by briefly running the motor with the coupling
or belt drive disconnected. If the motor runs in the wrong direction of rotation, have it corrected and verify direction of rotation
before reconnecting coupling or belts.
Summary of Contents for GIW MDX
Page 53: ...MDX en US 53 14 Notes...
