Goulds Pumps 3910 11th ed. - IOM - Manual (Page 36)

INSPECTIONS
Model 3910 parts must be inspected to the following
criteria before they are reassembled to ensure the pump will
run properly. Any part not meeting the required criteria
should be replaced.
NOTE: Clean parts to remove oil, grease or dirt.
Protect machined surfaces against damage during
cleaning.
CASING (100)
The casing should be inspected for excessive wear,
corrosion or pitting. Areas most susceptible are indicated
by the arrows in Fig. 22. Casing should be repaired or
replaced if it exceeds the following criteria:
1. Localized wearing or grooving greater than 3.2 mm
( 1
8
in.) deep.
2. Pitting greater than 3.2 mm ( 1
8
in.) deep.
3. Irregularities in case gasket seat surface which could
hinder or prevent sealing.
IMPELLER (101)
1. Inspect impeller vanes for damage. Replace if grooved
deeper than 1.6 mm ( 1
16
in.) or if worn evenly more
than 0.8 mm ( 1
32
in.). (Area “a” in Fig. 23.)
2. Inspect shrouds for damage. Replace if worn or bent
more than 0.8 mm ( 1
32
in.). (Area “b” in Fig. 23.)
3. Inspect leading and trailing edges of the vanes for pitting,
and erosion or corrosion damage. Replace as in No. 1.
(Area “c” in Fig. 23.)
4. Clean and check impeller bore diameter.
5. Check impeller balance. It should be rebalanced if it
exceeds the criteria of ISO 1940 G1.0.
NOTE: Balancing impellers to ISO 1940 G1.0 requires
extremely accurate tooling and equipment and should
not be attempted unless such tooling and equipment
are available.
BALL BEARINGS (112, 168)
1. Ball bearings should be inspected for contamination
and damage. The condition of the bearings will
provide useful information on operating conditions in
the bearing frame (228).
2. Lubricant condition and residue should be noted.
3. Bearing damage should be investigated to determine cause.
If cause is not normal wear, it should be corrected before
pump is returned to service.
NOTE: It is good practice to replace all ball bearings that
have been removed from their shaft fits. Always replace if
they are worn, loose or rough and noisy when rotated.
Replacement bearings must be of proper size and type.
4. Replacement bearings must be the same as, or
equivalent to, those listed in Table 3.
Table 4
Model 3910 Bearings
Group
Radial (Inboard)
Thrust
(Outboard) Grease Oil Mist
SA
SX
MX, LA
XLX
6210 C3Z
6212 C3Z
6213 C3Z
6218 C3Z 6210 C3
6212 C3
6213 C3
6218 C3 7310 BEGAM
7312 BEGAM
7312 BEGAM
7317 BEGAM
NOTE: Bearing numbers are based on SKF / MRC
designations.
36
3910-1
1th IOM 5/08
Fig. 22
Fig. 23