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Subject to change without prior notice
INSTALLATION OPERATION AND MAINTENANCE INSTRUCTIONS
VERTICAL TURBINE PUMP - NVT SERIES
Ref. No. NVT-IOM/2020/V.01
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Disconnect discharge head from the discharge piping.
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Clear a large area adjacent to the pump as a storage space for laying the pump horizontally for further
disassembly
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Place parallel timbers on the ground in the cleared area to support the pump horizontally.
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Remove anchor bolts from the discharge head bottom mounting flange.
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Fit shackles on the lifting lugs with bolts. Sling through the shackles and lift the pump vertically until the
pump strainer clears the foundation.
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Cover the opening in the foundation.
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Lower the pump into a horizontal position and lay it on to the timbers on floor.
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Remove the gland packing following the procedure described under section ‘
8
.
2
. Gland Packing Replace-
ment’.
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Remove the stuffing box cap screws and disassemble the stuffing box from the discharge head. Remove the
gasket.
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Before proceeding further make sure that the discharge head, each column sections and bowl assembly are
supported independently of each other using wooden blocks under them as shown in the Fig. No.
21
.
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Disconnect column pipe and discharge head by removing the bolts connecting them.
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Remove the discharge head carefully without damaging or bending the shaft.
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Disconnect the top column section by removing the bolts from the joint below it.
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Carefully remove the top column section without causing any damage to the shaft.
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Remove other column sections also as described above and this will expose the line shaft couplings and
bearing retainers.
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Whenever a line shaft coupling is exposed then the line shaft and coupling should be removed by holding
the lower line shaft and unscrewing the coupling and upper line shaft.
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Check if there are any nicks or burrs on the shaft and remove if any.
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After the removal of upper line shaft and coupling lift the bearing retainers out of the female register of the
flanged column and remove it.
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Complete the removal of all remaining columns, middle line shafts sections and their couplings by repeating
the previous steps.
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Remove cap screws that secure top bowl to intermediate bowl.
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Slide top bowl off the pump shaft.
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Remove cap screws and split thrust ring from pump shaft.
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Slide impeller off the pump shaft and remove the key.
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Gently strike the impeller using a fiber mallet and drive impeller off the shaft in cases where the impeller
is seized to the shaft.
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Repeat the above procedures until the bowl assembly is completely disassembled.
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Take each bowl and inspect it to confirm the locking method used in each particular bowl.
