SQFlex Service Instructions

51 / 60
5.8 Checking and replacing wear parts of centrifugal pumps
Bearing pos. 8
Check Replace
• Check whether the bearings are defective
due to sand or dry running.
• Remove the bearing pos. 8 by pressing it out
of the chamber pos. 9.
• Press a new bearing into the chamber from
the bottom side with the largest bearing diameter
against the bottom side of the chamber.
Top bearing pos. 6
Check Replace
• Check whether the bearing is defective. • Press the bearing pos. 6 out of the valve
housing (cylindrical shaft).
25 SQF (splined shaft): Press the bearing out
using a screwdriver, if necessary.
• Press the new bearing into the valve housing
from the bottom side.
Valve seat pos. 3 (only in 25 SQF)
Check Replace
• Check whether the rubber is hard or com-
pressed so that the valve cup pos. 2 touches the
metal.
• Free the valve guide pos. 70 where it is posi-
tioned under the recess of the valve casing. Pull
the guide and the valve cup pos. 2 out of the
valve housing.
• Push the valve seat pos. 3 out of the valve
housing by inserting a screwdriver between the
valve seat and the valve housing.
• Press the valve seat home in the valve hous-
ing with the flat side downwards.
Neck ring pos. 7
Check Replace
• Check whether the rubber is hard or worn as
this may reduce the head or flow rate.
• Prize the neck ring pos. 7 free of the chamber
pos. 9/10 or guide pos. 25 by inserting a screw-
driver between the neck ring and the chamber/
guide.
• Press the neck ring home in the chamber
pos. 9/10 or guide pos. 25. The following side of
the neck ring must be up:
• 25 SQF smooth surface
• 40 SQF "This side up"
• 75 SQF lip
sqflex_SI_US_WG.book Page 51 Thursday, October 1, 2009 3:27 PM