Routine Control; Disassembly And Assembly; Disassembly - Johnson Pump SPX MDR Manuel D'utilisation

MDR
3.4
3.5
3.5.1
MDR/EN (1206) 3.2

Routine control

• To avoid problems, regularly check pump noise, vibration, capacity, pressure gauge,
motor amperage draw, etc.
• Check impeller bearings for wear after 1 to 2 months of operation.
• Decide the control intervals according to wear and bearing diameter. Diameter of
impeller bearing
Table 1: Replace the impeller at the following inner diameters:
MDR45 7,25 mm
MDR75 10,35 mm
MDR85 10,35 mm
MDR105 15,50 mm
MDR116 15,50 mm
• If the impeller bearings only are replaced, they have to be reamed jointly to the
following diameters after assembly:
MDR45 7,10 ± 0,05 mm
MDR75
10,16 ± 0,04 mm
MDR85
MDR105
15,21 ± 0,04 mm
MDR116
• Check wear on the ceramic shaft and the ceramic wear plates. Replace when
necessary.
• If the pump will be stopped for a long time, drain and clean the interior of the pump.
• Check motor for accumulation of dust or dirt, which might influence motor
temperature.

Disassembly and assembly

See drawing, chapter 4.
Always wear suitable safety clothing. Clean the pump carefully before disassembling.

Disassembly

1 Place the pump vertically with the motor facing downwards and the pump body
upwards.
2 Remove the screws (pos 10) and the pump body (pos 8).
3 Remove the front wear plate (pos 4), the impeller (pos 6), O-ring (pos 7), shaft (pos
5) and rear wear plate (pos 4). MDR105 and MDR116 have only the rear wear plate.
The front wear plate is integrated in the impeller.
4 Remove the magnet housing (pos 3) including the reinforcement (pos 19 – not
available for MDR45).
5 If the motor, drive magnet or flange is to be replaced, loosen the two locking screws
(pos 2) locking the drive magnet onto the motor shaft. The screws can be reached
through the assembly hole in the flange (see chapter 4). Remove the drive magnet
(pos 13).
6 Remove the screws (pos 12) and the flange (pos 1).
7 Check and clean all the parts which will be reused.
Installation and maintenance 15