12
2 BW 70 en
8
Troubleshooting
Valve leakage at the shut-off disc
□
Never close the valve by force: irreparable damage may
occur.
□
Check if the energy supply is connected.
□
Check if the closed position of the actuator is in accor-
dance with the closed position of the disc.
□
Check the sealing surface of the disc and the sealing ele-
ment for damages. If necessary dismantle the disc.
□
Check if there is foreign material between the disc and
the sealing element. If necessary, remove foreign mate-
rial or deposits.
□
If necessary, replace the damaged parts.
For dismounting, see chapter maintenance.
Observe the notes in Chapter 10. “Cleaning and mainte-
nance”.
Escape of fluid or gas...
...at the gland packing
1.
Check if the gland is still precompressed by the disc
springs. Possibly the disc springs are damaged. In this
case you must change them
2.
If the precompression is too less you must retighten the
nuts, but not up to the stop thereby the disc springs
will be damaged.
3.
If the precompression of the disc springs is in order
then the gland packing is damaged and you must
change it
Notes for dismounting are found in the chapter on mainte-
nance.
…at the cover plate
Check to see that all cover screws are tightened well. If nec-
essary, change the sealing.
Notes for dismounting are found in the chapter on mainte-
nance.
9
Safety instructions
Please pay attention to the following safety instructions
when doing maintenance and when operating the high per-
formance disc valve:
1.
For safety reasons, you are not allowed to carry out
modifications to the method of operation of the disc
valve or its actuator.
2.
Only specialist personnel are allowed to carry out
installation work on the high performance disc valve.
3.
There is a danger during the functional test that the
disc of the valve may move uncontrollably and sud-
denly due to the energy supply. Therefore, ensure that
the valve can not move or tip under any circumstances
during the functional test.
4.
Take care during the installation of valves with the
safety position "spring open". If the disc extends over
the installation length of the valve, the valve must be
closed before installation (pneumatically, hydraulically,
etc.). Ensure in particular that the energy supply is
safely secured and cannot be damaged or torn in any
way during installation.
If the energy supply is suddenly interrupted, the valve
opens abruptly. This can lead to severe injury and dam-
age to materials.
5.
During possible maintenance work, there is considera-
ble risk of injury by the accidental use of the remote
control. If you plan to perform remote control for the
work with the valve, ensure that the energy supply of
the actuator is switched off.
6.
Ensure that the cleaning substance will not cause any
unwanted chemical reactions in connection with possi-
ble residues in the high performance disc valve.
7.
If you work in the area of the sealing surface of the disc,
secure the latter with wooden wedges to prevent the
risk of crushing. Take care that by doing this the sealing
surface of the disc is not damaged.
8.
If the seals are destroyed by a medium which is too hot,
the medium used may leak at the shaft.
10
Maintenance
10.1
Cleaning and maintenance interval
Series BW high performance disc valves are, to a large
extent, maintenance-free.
Check the valve regularly for its tightness. We recom-
mends replacement of the metallic sealing element
(321) and the packing rings (451) on demand or in criti-
cal applications after a period of two years at most, see
Fig. 14.
When allocating cleaning or maintenance work to qualified
outside companies or qualified outside personnel, draw
attention to the risk of the medium used and, if necessary,
the existing residues. Make this IMO available to these per-
sonnel.
Fig. 14
Replacement of metallic sealing element and
packing rings
If the medium has contamination which could impair the
tightness of the valve, the sealing surface of the disc must
be cleaned regularly. Contamination can damage the seal-
ing surface of the disc or sealing element.
Cleaning substances which could attack the sealing surface
or the metallic seal shall not be used to remove residues.
Use water, soap suds or other solvents as well as a soft, lint-
free cloth.
Never use cutting, scraping or grinding tools like files or
emery paper. Do not use solvent containing substances
which can cause unwanted chemical reactions with the
residues of the medium or/and attack the seal.
451
321
