(0) 2018/05
7. Maintenance
19
7.6.
REPLACING THE SEAT SEAL
1.
Put the plug shaft in a vertical position—for example,
with a bench clamp—so that the shaft is kept stable and
no damage is caused to the mating surface of the conical
seal. Do not press the shaft too much if using a bench
clamp.
2.
Remove the used seal using a screwdriver or a sharp
hook-shaped tool. Make sure not to damage the mating
surface of the seal.
3.
Lubricate the new seat seal with soapy water if necessary
to facilitate installation.
4.
Insert the seal in the plug shaft seat accommodation so
that its edges are inside the accommodation. Preferably,
the seal should fit within the part of the section that has
the greatest diameter, as shown in the figure.
5.
Then, with the help of an appropriate tool (not piercing),
press the edge of the seal that has not yet fit into the
accommodation, as shown in the figure.
6.
This operation should be done around the entire
diameter, applying the tool in the sequence
1-2-3-4-5-
6-7-8
as shown in the bottom figure. Always press on
opposite sides. Once you get to the last step of this
sequence, repeat the process until the seal is completely
inside the accommodation.
7.
Press the seal with your fingers to make sure it is well
seated. Make sure there are no parts projecting due to
poor positioning of the seal.
The following tools are needed to assemble/disassemble the
valve:
1 crescent spanners 15 mm and 1 crescent spanners 17 mm – To remove the plug shaft DN 25.
2 crescent spanners 17 mm – To remove the plug shaft DN 40 to DN 100.
Crescent spanner 13 mm – For the clamps.
Appropriate tool (not piercing) to mount the seat seals.
Allen key per the table:
Proceed with caution. Personal injury can occur.
Never directly disassemble the clamps from the valve Reading the instructions carefully.
Valve/actuator assembly and disassembly should only be done by qualified persons.
Zone
DN 25/40 DN 50/65/80
DN 100
Lantern
5 mm
6 mm
10 mm
Cap
4 mm
5 mm
8 mm
