GORMAN-RUPP PA4C60-4045H, Инструкция по установке, эксплуатации и обслуживанию

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PA SERIES OM−06078
MAINTENANCE & REPAIR PAGE E − 20
Impeller Installation
(Figures 4 and 9)
Inspect the impeller, and replace it if cracked or
badly worn.
Install the same thickness of impeller adjusting
shims (52) as previously removed. Install the shaft
key (46) and position the impeller on the shaft. See
Figure 9, and use a section of pipe, washers and a
long, 5/8−11 UNC capscrew to press the impeller
onto the shaft until fully seated (
do not use the im-
peller lock screw ). Make sure the seal spring
seats squarely over the step on the back side of the
impeller.
When installing the impeller, the capscrew
must be long enough to enter the shaft at
least eight full threads. Otherwise, damage
to the shaft threads may occur.
Shaft
Key
Pipe
Washers
Long
Capscrew
Figure 9. Installing Impeller
A clearance of approximately .030 inch (0,76 mm)
between the impeller and the back plate is recom-
mended for maximum pump efficiency. Measure
this clearance, and add or remove impeller adjust-
ing shims as required.
The pump casing must be installed in order to
properly torque the impeller lock screw (48). After
the impeller clearance has been set, install the
pump casing as described below, then proceed as
follows to install the impeller washer (49) and lock
screw.
NOTE
To ensure proper torquing of the impeller lock
screw, make sure the tapped hole in the impeller,
the impeller washer and the impeller lock screw are
clean and dry (it is not necessary to remove the pro-
tective coating from the capscrew). It is recom-
mended that a new impeller lock screw be used
whenever the impeller is removed. To ensure the
proper lock screw material and specifications, use
only genuine Gorman-Rupp replacement parts.
With the pump casing installed, coat the threads of
a new impeller lock screw with Loctite Threadlock-
er No. 262" or equivalent compound, and install
the impeller washer and lock screw. Immobilize the
impeller by inserting a wood block through the dis-
charge opening or cleanout cover opening as de-
scribed in
Pump Casing And Wear Ring Remov-
al . With the impeller immobilized, torque the impel-
ler lock nut to 110 ft. lbs. (15,2 m. kg.).
Pump Casing Installation
(Figure 4)
Install the casing gasket (44). Use a suitable hoist
and sling to position the casing over the impeller,
and secure it to the back plate with the capscrews
(40).
Suction Cover and Wear Ring Installation
(Figure 4)
If the wear ring (47) was removed from the suction
cover (50), chill the wear ring by refrigeration and
press it into the suction cover bore until fully
seated.
The wear ring must seat squarely in the
suction cover; otherwise binding and/or
excessive wear will occur.
Install the suction cover gasket (4). Use a suitable
hoist and sling to position the suction cover in the