Repair work
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V 1.0
M8
17 Nm
28.7 Nm
M10
33 Nm
58 Nm
M12
57 Nm
100 Nm
M16
140 Nm
245 Nm
M20
273 Nm
494 Nm
7.2
Replacement of various pump parts
Replacing impeller and pump housing
• Loosen the cylinder head screw with hexagon socket on the sealing housing and screw it off.
• Secure the pump housing using suitable aids e.g. lifting devices, and pull it off the sealing housing. Set down
on a safe base.
• Fix the impeller in place using suitable aids, loosen the impeller attachment (cylinder head screw with hexagon
socket) and screw this out.
Watch out for the screw locking device.
• Pull the impeller off the shaft using a suitable removal tool.
• Clean the shaft.
• Push the new impeller onto the shaft.
Make sure that the mating surfaces do not become damaged.
• Screw a new impeller attachment (cylinder screw with hexagon socket and a new screw locking device) back
into the shaft. Fix the impeller in place and tighten the cylinder head screw.
• Insert the pump part onto the sealing housing and attach using hexagon nuts.
• The impeller must be able to be turned by hand.
Split ring replacement
The split ring and raceway determine the gap between the impeller (raceway) and the suction muff (split ring). If this
gap becomes too big, the pump‘s pumping capacity drops and/or blockages occur. Both rings have been designed
in such a way that they can be replaced. This reduces wear on the suction muff and impeller and minimises spare
parts costs.
Replacement of the floating-ring type shaft seal
Replacement of the floating-ring type shaft seal requires basic knowledge and specific special knowledge of these
sensitive components. In addition, the pumps have to be dismantled to a major extent for this work to be carried out.
Only use genuine spare parts for replacement.
Checking and replacement of these parts is carried out by the manufacturer during general overhaul or by specially
trained personnel.
The Chapter “Explosion protection” in the Enclosure must be heeded for explosion-proof pumps!
