Jesco MEMDOS E, Operation Manual

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The diaphragm can be replaced as follows:
1. The delivery rate of the dosing pump is set to zero while the motor is running.
This moves the diaphragm to the front end position.
2. Switch off the pump.
3. The head is removed using an appropriate tool. (see Fig. 1)
4. Grasp the edge of the diaphragm and turn it to the left. On the E/DX 50, 75, 76, the support plate
located behind the diaphragm is also removed.
IMPORTANT!
Before fitting a new diaphragm, the area around the diaphragm flange and support plate must be cleaned to
remove any chemicals, otherwise these might corrode the back of the diaphragm. (see Fig.
2)
5. If present, the support plate is pushed onto the threaded sleeve with the curved side facing towards the
diaphragm. (see Fig. 3)
6. The new diaphragm is turned clockwise until it is screwed securely into the diaphragm rod (grease the
thread). This causes the flat side of the support plate (if present) to be pressed against the end of the
diaphragm rod.
7. The dosing pump stroke is now set to maximum while the motor is running. Switch off the motor. The
diaphragm is now seated in the groove of the diaphragm flange.
8. Fit the dosing head at the front. Tighten the screws alternately,
e.g. top left – bottom right – top right – bottom left. (see Fig. 4). For the required tightening torque, see
table 11.1.
IMPORTANT!
The diaphragm will not be sufficiently sealed if the tightening torque is too low. The dosing head may be
damaged if the tightening torque is too high.
9. After connecting the dosing lines, the dosing pump is started as described in "Start-up" (section 9).
10. If the diaphragm becomes worn with unusual frequency, try to determine the cause. For the possible
causes, please refer to "Troubleshooting" (section 14).
1 2
3 4
Maintenance | Operation & Maintenance Instructions |
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