Wear rings
•
Casing wear rings are supplied as standard to maintain proper running clearance and to minimize
leakage between the suction and discharge chambers in the casing. Each casing ring is held in
place by a single anti-rotation pin located in a milled slot at the horizontal parting surface.
•
Optional impeller wear rings are available on all pump sizes. The impeller wear rings are held in
position by axial setscrews. Field installation of impeller rings requires a re-machining of the impel-
ler hubs.
•
The casing rings remain the same for designs with or without impeller rings.
Shaft
The shaft is a heavy-duty design that minimizes deflection and vibration. The shaft deflection is a maxi-
mum of 0.051 mm | 0.002 in. at the stuffing box face under the worst operating conditions. The shaft on
M, L, and XL group pumps is completely dry with gasket seals between the impeller hubs and shaft
sleeves. The S group does not have a completely dry shaft. The S group is standard with a 420 stainless
steel shaft. The M, L, and XL sizes have an ANSI 4140 steel shaft standard with an option for 316 stain-
less steel.
Shaft sleeves
The M, L and XL group pumps have standard shaft sleeves. They are keyed to the shaft at the impeller
and held axially in place using threaded sleeve nuts. The S group pumps are standard without shaft
sleeves, but sleeves are available.
Stuffing box
Non-asbestos stuffing box packing is standard. The stuffing box contains split lantern rings and renewa-
ble stuffing box throat bushings. Tapped openings are provided for water sealing from either the pump
casing or an outside source. Bypass piping is optional. Two-piece, investment cast, 316 stainless steel,
non-quench glands are standard on all 3410 pumps.
Mechanical seals
•
Mechanical seals are available as an option on the Model 3410. Oversize stuffing box bores are
standard on pumps with factory-installed mechanical seals. This provides greater flexibility and an
improved operating environment.
•
Pumps that are supplied with standard packed boxes can be converted to mechanical seals in the
field. This conversion requires either re-machining of the stuffing box to accommodate the mechani-
cal seal or re-machining of the gland to adapt to the existing stuffing box. If the stuffing box bores
are re-machined, then all standard Model 3410 mechanical seals and the standard I.D. pilot glands
can be used.
•
Balanced seals require conversion to stepped sleeves. Most unbalanced mechanical seals will fit in
the standard packed box bores, but this requires re-machining the I.D. pilot off the glands. In this
case, the glands must be centered on the shaft or the sleeve using a feeler gauge.
•
Pumps supplied with mechanical seals can also be converted to packed boxes in the field. A car-
tridge conversion kit is available and includes a box of fittings plus sleeves to convert oversize
bores to standard packed-box bores.
Bearings
•
The Model 3410 is standard with double-row ball thrust bearings and a single-row deep groove ball
bearing at the coupling end. There are only two sizes of bearing housings and bearings used on the
Model 3410 product line. The S and M groups use identical bearings, as do the L and XL groups.
The thrust bearing is held in position with a tapered snap ring and is locked in the thrust bearing
3.1 General description
Model 3410 Installation, Operation, and Maintenance Manual
21
