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Changing valve sleeve of Enclosed/Sealed
model valve PVE/S
See Figure 4 for part numbers.
1.
Depressurize and drain the pipeline.
2.
Open the valve and detach it from the pipeline.
3.
Open the screws (part 7) between the valve body halves
and detach the lower part of the body.
4.
If the valve has opening tags (part 17), detach them from
both upper and lower pinch bars, 8 pcs screws.
5.
Take out the damaged sleeve and put in a new one. If the
sleeve is stiff, loosen nuts (part 9) and take the sleeve out.
If it is still impossible to remove the sleeve, detach the
lower pinch bar by pulling it smoothly out and ensuring
not to damage the seals (part 20, 21) with threads of
lower pinch bar.
6.
Clean all the parts which have been in contact with the
process medium.
7.
Put in a new sleeve. Remember to fix the opening tags if
applicable.
8.
Check the condition of the side bushings (parts 5).
Replace the body sealing (part 16) between the body
halves and the seals (part 20, 21) and the seal in the
center bushing (part of actuator). A worn sealing and/or
worn bushings may cause leakage to the environment in
the event of a sleeve breakage.
9.
Assemble the valve and adjust the pinch bars before
installing the valve to the pipeline.
At sleeve change, it is always important to check
and adjust the position of the pinch bars. See 7.3.
7.3 Adjusting the valve
After every sleeve change, the closing of the valve has to be
checked and adjusted. A wrong adjustment may shorten the
lifetime of the sleeve and cause leakage from the valve when
the actuator is in the closed position.
Crushing and cutting hazard.
Do not put your hands or fingers between the
moving parts when the valve cycles. Do not
energize the actuator before the valve is properly
attached to the pipeline.
Disconnect and de-energize the actuator before
installation and maintenance work.
4PV70EN - 5/2023
WARNING!
Before reinstallation of the valve into the pipeline:
1.
Close the valve with the actuator.
2.
Adjust the pinch bars parallel to each other with the
nuts, which are on both sides of actuator fixing plate
(Figure 17, nuts 1 and 2). From one end of the sleeve an
even, narrow light strip should be visible on the whole
squeezed section of the sleeve or symmetrically on both
sides (Figure 17 and Figure 18, dimension X).
3.
Tighten both nuts (1) equally so, that the strip of light
disappears (Figure 19). Loosen the lower nuts (2) if
necessary.
4.
Set the lower nuts (Figure 20, nut 2) Y mm from the
attachment plate (see the dimensions Y in Table 2).
5.
When the nuts (nut 1) on the upper side of the
attachment plate are tightened, the lower pinch bar rises
and causes a sufficient squeeze on the sleeve to close the
flow against the pressure in the pipeline.
6.
After this has been done, open the valve and it is ready to
be installed to the pipeline.
If the valve is hand wheel operated, it is enough to check that
the pinch bars are parallel, and the light slit is shown (Figure
17 and Figure 18, dimension X ).
A sufficient squeeze is achieved by turning the hand wheel
1/3...3/4 rounds after the valve feels tight.
Table 1.
Tightening values for manual valves
Pipeline pressure
1 bar (15 psi)
PN 10 bar (150 psi)
PN 25 bar (375 psi)
If the valve is supplied with a reduction gear, the number of
rotations is multiplied by the gear ratio.
Needed rotations
appr. 1/3 of a hand wheel rotation
appr. 1/2 of a hand wheel rotation
appr. 3/4 of a hand wheel rotation
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