Xylem MPAI - Manual (Page 97)

Installation, Operating and Maintenance Instruction
Model MP, MPA, MPAI
MP 100-english page 93 Revision 04
Article No 771074011 Issue 11/2011
A number of methods can be used for repair work.
Depending on the area (A to G) the following methods
can be used. In certain cases, it is better to use new
parts.
"A": Reworking the outer diameter (levelling), the gap
width should not exceed the value stated in the
table. The new surface should be as fine as
possible (grind). Polish the surface using a
grinding belt.
"B": New Part (only use original parts)
"C": .) ......... Replace impeller (only use original
parts)
.) ......... Turn away impeller hub and make an
appropriate spacer sleeve (take care with
material selection)
It might be necessary to rework the bore in the
diffuser
"D": .) ......... Replace impeller (only use original
parts)
.) ......... Rework seal (level), hollow out casing
and insert ring (split ring).
"E": .) ......... Replace impeller (only use original
parts)
.) ......... Rework seal (level), hollow out casing
and insert ring (split ring).
"F": The precise gap width in this area is only
necessary in special cases (shaft seal with
discharge line). In normal cases, the gap width is
unimportant. The value specified in the table may
be exceeded.
"G": New parts (only use original parts)
Bearing play has a direct influence on the smooth
running of the pipe. If pump oscillation rises
perceptibly this can indicate that the bearing is
worn.
When carrying out repairs always replace the
bearing bush (23) and bearing sleeve (21).
9.Reassembly
9.1 Preliminary work
Assembling a pump consisting of new parts requires
preliminary work. Therefore some of the following
points might already have been carried out when the
pump is reassembled. Always use the sectional
drawing contained in the Appendix of the Operating
Instructions.
Clean all components and remove any rust.
Suction housing (3) (only for MP): Screw in and
secure throttle part (DR).
A bore with approx. 4mm diameter must be
provided to ventilate the sealing chamber.
Depending on the location of the lines of the
suction casing, the bore must always be in the top
position (use one of the three depressions cast)
Screw in stud bolts (S2)
Pressure casing (4): Code "P" Screw in and
secure screw plugs (V2)
Code "SA,SB etc." Screw in and secure throttle
part (DR) (use correct bore)
Screw in stud bolts (S2)
Stuffing box casing (19): Hammer in pin (S4)
Screw in stud bolts (S3)
Sealing cap (18): Hammer in pin (S4) and pin (S7)
(if present)
Bearing flange (10): Screw in stud bolts (S5)
Bearing cap (12): Screw in lubricating nipple (G)
Inside bearing casing (54): Press in bearing bush
(21)