Overhauling; Dismantling Procedure - DECCAN DP 50/30A Installation, Operation And Maintenance Manual

I N S T A L L A T I O N , O P E R A T I O N A N D M A I N T E N A N C E M A N U A L

OVERHAULING

8.
With normal daily operating spell, the pump will be due for overhaul after about 5000
working hours. This should be done by skilled personnel. Please refer to the cross sectional
drawing while dismantling and reassembling the pump.

8.1 DISMANTLING PROCEDURE

Store all loose components carefully in a wooden box. Remove sealing connection given to
lantern ring/mechanical seal, temperature indicator, etc.
 Disengage pump coupling from motor coupling. Drain the pump by removing drain
plug and opening air vent valve.
 Remove the nuts and locating pin jointing the upper half casing and lower half
casing.
 Remove all insert joints nuts at both ends.
 Insert a screw driver or peg bar into the slot between the two halves and separate
and lifting off the upper half casing. Remove the upper half casing, taking enough
care not to damage the impeller and casing wear ring.
 Tap the inserts with the soft hammer to break the seat between the insert and lower
half casing and lift the rotating unit out of the lower half casing so that none of the
parts will be damaged. Take out the rotating unit & keep it on rubber or wooden
sheet in clean7 dry place for further dismantling purpose.
 Remove the pump coupling and coupling key.
 Remove the four hex screws from each bearing housing and remove the bearing
housing from bearings take it off the shaft.
 Remove bearing lock nut and lock washer from NDE side. Remove NDE bearing
from shaft by the use of bearing puller. Remove driving end bearing in the same
manner.
 Remove oil seals from the insert from DE & NDE side. Remove shoulder Rings from
the shaft by using puller.
 Remove liquid deflector from shaft.
 Remove the gland nuts from each gland. Remove gland, gland packing & lantern
rings from insert.( For Soft Packed Pumps)
 Slide inserts off the shaft.
 Remove grub screw holding mechanical seal & slode off mechanical seal on both
sides from the shaft. .( For Mechanical seal Pumps).
 Take out casing rings on DE & NDE side
 Unscrew DE side shaft sleeve and slide it off the shaft from DE side. Remove the
impeller from shaft. Remove the impeller key( If it is CCW)
 Unscrew the NDE side shaft sleeve and slide it off the shaft from NDE side(If it is
CCW)
 Unscrew NDE side shaft sleeve and slide it off the shaft from NDE side. Remove the
impeller from shaft. Remove the impeller key( If it is CW)
 Unscrew the DE side shaft sleeve and slide it off the shaft from DE side(If it is CW)
20 | P a g e D E C C A N I N D U S T R I E S