Leser 411 Instructions De Service page 26

5. Loosen lock nut (19).
6. 1 ) Turn adjusting screw (18) to the required
set pressure.
Pay attention to the admissible pressure
range of the spring!
Clockwise turning of adjusting screw
increase the spring tension, giving a higher
set pressure.
Anticlockwise turning of adjusting screw
reduces the spring tension, giving a lower set
pressure.
7. Reassemble in reverse order and lock at the
E
set pressure.
40.4 40.4
40.1
40.1
18 18
13.2 Lifting device H4
1. Loosen the spring cover (40.1.1) and
simultaneously press the lever (40.1.6) in the
direction of the bonnet so that the lifting fork
(40.1.5) comes free.
2. Remove the lever cover (40.1.1).
3. Loosen the lock nut (19).
1)
4. Turn adjusting screw (18) as described in
lifting device H3. Pay attention to the ad-
missible pressure range of the spring!
5. Reassemble in reverse order and lock at the
set pressure.
40.1.5
40.1.1
13.3 Spring replacement
The following items refer to the figures shown in
the LESER Product Catalogue.
1. Loosen the existing lead seal.
2. Press the lever (40.6) towards the middle
until it reaches the stop so that the lifting
fork (40.5) no longer holds the spindle cap
(40.12).
3. Loosen and remove the lever cover (40.1).
4. Loosen the spindle cap (40.12) from the
spindle (12), remove the securing ring
(40.14) and the pin (40.13).
26
19
19
40.3
40.3
40.6 40.6
Fig. 1
40.1.6
18
19
Fig. 2
5. Loosen the lock nut (19) of the adjusting
screw (18).
6. 1)
Turn the adjusting screw (18) anticlock-
wise to remove all spring tension.
7. Remove the hex. nuts (56) from the flange
of the bonnet (9).
8. Lift off the bonnet (9).
9. Remove the upper spring plate (16).
10. Lift off the spring (54) and remove lower
spring plate (16) and split rings (14).
11. Remove spindle (12) with guide (8) and
disc (7).
12. Carefully clean seat (5) and disc (7), and if
required body internals.
13. Refit spindle (12) with guide (8) and disc (7).
14. Fit the split rings (14) into spindle groove
and retain with the securing ring (59); slip
on lower spring plate (16) to locate on split
rings (14).
15. Replace spring (54).
16. Slip on the upper spring plate (16) onto the
spindle (12).
17. Align adjusting screw (18), and bonnet (9).
over the spindle (12) and refit.
18. Fit and tighten the hex. nuts (56).
1)
19. Load the spring (54) to obtain the required
set pressure. Clockwise rotation of
adjusting screw (18) increases pressure.
Anticlockwise rotation of adjusting screw
(18) reduces pressure.
20. Tighten the lock nut (19) onto the adjusting
screw (18).
21. Refit and secure spindle cap (40.12) by pin
(40.13) and securing ring (40.14).
22. Screw-on the lever cover (40.1).
23. Pull the lever (40.6) towards the middle so
that the lifting fork (40.5) is pushed under
the spindle cap (40.12).
24. Test spindle will lift correctly by pulling
lever.
These instructions are applicable for relief valves,
safety valves and safety relief valves.
1)
Caution: During all work the spindle has to be
secured against twisting in order to prevent
damage to the sealing surfaces.
The following points should be noted:
The pressure setting is wire-locked and
sealed against unauthorized alteration. The
rules and standards, agreed by the manu-
facturer, require the fitting of a name plate
stating the correct valve data. The manu-
facturer cannot be held responsible for any
changes to set pressure or other alterations
after despatch from the factory. Necessary
modifications should only be made by
authorised distributors of LESER or under the
supervision of the TÜV or any other
competent inspection authority.