V" Belt Drive Tensioning Method; Impeller Running Clearance; Shaft And Bearing Replacement; Cleaning Or Replacing Check Valve - ITT MARLOW Serie Manual De Instalación, Operación, Mantenimiento

"V" BELT DRIVE TENSIONING METHOD

Before attempting to tension any drive it is important that
the sheaves be properly installed and aligned. The V-belts
should be placed over the sheaves and in the grooves
without forcing them over the sides of the grooves.
Step 1: With all belts in their proper groove adjust the
centers to take up all slack and until the belts
are fairly tight.
Step 2: Start the drive and continue to adjust until the
belts have only a slight bow on the slack side
of the drive while operating under load. See
drawing below.
Step 3: After a few days operation the belts will seat
themselves in the sheave grooves and it may
become necessary to readjust so that the drive
again shows a slight "bow" in the slack side.
Too Tight
Slight Bow
The drive is now properly tensioned and should oper-
ate satisfactorily with only an occasional readjustment to
compensate for belt and groove wear.

IMPELLER RUNNING CLEARANCE

The impeller running clearance, the distance between the
impeller vanes and wear plate, is adjusted at the factory
prior to shipment to .020" – .030". To adjust this clearance
in the fi eld, shut down the pump, disconnect power sup-
ply to the pump and use the following instructions.
1. Drain pump casing (1) completely by removing drain
plugs (2) from both suction and discharge chamber.
2. Remove clean-out cover (83) by unscrewing the two
hand knobs (81).
3. Reach inside the pump casing through the clean-out
hole with a feeler gage and measure the gap between
the impeller vanes and wear plate (89). Measure this
gap at each impeller vane. If this gap is not within
the allowable limits of .020" – .030", adjust this
clearance as follows:
(a) Unscrew the three jack-screws (112) and jam nuts
(111). Partially loosen the bearing carrier cap-
screws (45).
(b) Adjust the jack-screws (112) and capscrews (45)
until the front clearance between the impeller
vanes and wear plate falls within the allowable
range of .020" – .030". Tightening the jack-screws
(112) will increase the front clearance and tight-
ening the capscrews (45) will decrease the front
clearance.
Tighten one set of screws and loosen the other
to go in the direction required. Tighten locknut
(111).
Note: maximum allowable bearing carrier (110) pull back
movement is / ", (i.e. from the condition when impeller is
1
8
"just" touching the wear plate you can push back the
bearing carrier assembly by

SHAFT AND BEARING REPLACEMENT

If shaft or bearing replacement is necessary, follow these
instructions. (Shut down the pump and disconnect power
supply to the pump before working on pump.)
Too Loose

CLEANING OR REPLACING CHECK VALVE

Shut down the pump and disconnect power supply to the
pump before working on pump.
Drain pump casing (1) completely by removing drain
plugs (2). Access to suction check valve can be made by
removing the check valve cover plate (76) from the top of
the suction chamber of pump casing.
Reaching through the check valve cover plate hole,
remove the two shoulder screws (118) and check valve
keeper plate (53). Now slide off check valve (51). Pull the
check valve assembly out of the pump casing through the
cover plate hole. Inspect the sealing surface of the check
valve and make sure it is in good condition and free of
debris.

CLEANING IMPELLER

Drain pump casing completely by removing drain plugs
(2). Remove hand knobs (81), remove clean-out cover
(83) and using coat hanger remove debris from the impel-
ler eye area and if necessary wash it off with garden hose.
Check o-ring (84) on the clean-out cover, replace it if
necessary.

HYDROTEST

NOTE: If hydrostatic test is required in the fi eld, it must
be performed with suction check valve removed or with
partially open suction check valve.
1
1. Install the front (impeller end) bearing (36) on the
shaft (38).
2. Slide the carrier retaining ring (106) onto the shaft
(38).
3. Install the rear (coupling end) bearing (117) on the
shaft (38).
4. Install the retaining ring (108) onto the shaft (38).
Add shims (107) between the retaining ring (108)
and the bearing (117) if required to lock the bearing
(117) on to the shaft axially.
5. Install o-ring (109) into the bearing carrier groove.
6. Slide the bearing carrier (110) with o-ring over the
rear bearing such that rear bearing slides into the
bearing carrier (110). Install the retaining ring (106)
in place.
7. Insert shaft assembly with bearings and carrier into
the housing (31).
1. The maximum allowable hydrotest pressure for these
pumps is:
3DTH EL and EB
4DTH EL and EB
6ETH EL and EB
8GTH EL and EB
10GTH EL and EB
/ ").
8
130 psi
85 psi
7