15
7- DISASEMBLY AND REASSEMBLY
• Follow the safety precaution measures outlined in “safety instructions”.
7.1- Disassembly
• Close all valves in the suction and discharge lines, and drain the pump by opening the drain plug and the air
plug.
• Disconnect the stuffing boxes flushing pipes.
• Remove coupling guard and other safety guards (see section safety guard).
• Remove all casing main joint nuts and dowel pins.
• Separate the casing halves, lifting off the upper half casing. This reveals the pump internals (impeller, wear
rings) for inspection.
• Unscrew the bolts which are connecting the bearing housings to the bottom half casing.
• Remove bearing covers and bearing end covers.
• Pull the bearing housing off the bearings.
• Unscrew the shaft nuts and lock washers.
• Pull the bearing off the shaft and remove.
• Remove in sequence bearing covers, throwers, spacer sleeves, stuffing boxes, shaft protecting sleeves, wear
rings, impeller and impeller key.
• Clean all the parts, replace damaged or worn-out ones.
7.2- Reassembly
• Reassembly proceeds in reverse sequence to dismantling as described in (section 7.1). You may find the attached
drawing useful. the following points should be noted more particularly.
• Never use old o-rings and make sure the new o-rings are the same size as the old ones.
• Before mountling the shaft protecting sleeves inspect the condition of their rubbing faces. Use new sleeves if
the old ones are badly worn, scored or rough.
• the joint faces of the casing halves are sealed with liquid sealing compund. The joint faces should be thoroughly
cleaned before reassembly and coated over again with sealing compund. NEVER USE A PAPER GASKET BETWEEN
THE TWO FACES.
The following tightening torques must be taken into consideration when tightening
the bolts and nuts during installation.
7.3- Tightening Torques
ATTENTION
Table 5
Table 5 (continue)
Tightening
Torques (Nm)
Tightening
Torques (Nm)
Thread
Diameter
7
20
40
65
100
M6
M8
M10
M12
M14
M16
M18
M20
M22
M24
Thread
Diameter
130
140
140
140
200
