Cepex PVC-U Manual Del Usuario página 10

7. OPERATION AND MAINTENANCE INSTRUCTIONS
It is recommended that the condition of the sealing gasket be regularly checked, since it may show signs of mechanical wear due
to pressure, handling and contact with the liquid. The sealing gasket should be greased in the disc contact area (the grease must
be compatible with the materials of the gasket and the disc). It is also advisable to regularly check that the flange fixing nuts are
tightened correctly, as per the recommended torque values specified above (T5.1).
Periodic movement should be carried out to avoid the locking of the valve during long periods of time when it is in a closed
position. It is advisable that the liquid be passed through before the valve is manoevred.
7.1 REPLACING THE SEALING GASKET
If the sealing gasket needs to be replaced, proceed as follows:
• Ensure that the system is depressurised by releasing the pressure and emptying the pipes, follow-
ing the specific safety regulations for each product. Also check the temperature of the liquid and
follow safety standards for temperature.
• Remove the valve from the installation.
• Remove the handle, screws (20), nuts (21) and throttle plate (17).
• Remove the ring (8). Take off the cap (7) and remove the screw (12).
• Tap on the shaft (6) with a rubber mallet until the bearing (4) is exposed from the bottom (Fig. 11).
• Once the bearing is out, remove the shaft (6), turn it and re-insert it (Fig. 12) from the bottom.
• Tap again until the bearings (4 and 5) emerge from the top. Remove the shaft again.
• Remove the disc by pressing in the direction of the liquid flow.
• Remove the sealing gasket. Fit the new sealing gasket; it needs to be folded and positioned so that
it lines up with the shaft, according to the gasket indicator tab (Fig. 13).
WARNING: Before installing the new gasket, check the condition of the O-rings (9 and 11).
Fig. 13
8. MOUNT AND DISMANTLE THE ACTUATOR
If the actuator or the valve needs to be replaced, proceed as follows:
1. Move the butterfly valve to the closed position.
2. Depressurise and drain the plant or the plant component.
3. Depressurise the control medium.
4. Remove the control medium line(s) from the actuator.
5. Remove the screws, the washers and the nuts (7, 8 and 9, Fig. 1).
6. Remove the assembly of the pneumatic actuator (4) with the mounting clamp (5) from the bare
shaft valve (Fig. 14).
7. Remove the screws (6) in order to dismantle the actuator from the mounting clamp.
8. In case the actuator needs to be be replaced by a handle, also remove the coupling bush (4 Fig.1).
In order to assemble a new actuator or a new valve, proceed in the opposite direction to the descrip-
tion above.
10
INDUSTRIAL PNEUMATIC BUTTERFLY VALVE ENGLISH
Fig. 11 Fig. 12
Fig. 14
3
A
2
A
1
A
A