Maintenance; Screw Connections; Cleaning; Modification Of The Overflow Valve - Richter GU/F Series Installation And Operating Manual

Series GU/F
9

Maintenance

Overflow valves must be checked for
operability at regular intervals according to
the national regulations (in Germany: UVV -
pressure vessels, VBG 17 § 32 and TRD
601 sheet 2, paragraph 3.4).
♦ The intervals for regular checks are to be laid
down by the customer in line with the operating
conditions.
♦ The lifting lever 238 allows the valves to be
actuated from outside, they then open at the
operating pressure available. For lifting, the pres-
sure is to be at least 85% of the test pressure.
♦ All repair work is to be performed by qualified
personnel using the appropriate tools.
♦ For the arrangement, designation and item
numbers of all parts of the valve, see Section 10.
♦ Spare parts are to be ordered with all the details in
acc. with the valve identification.
♦ Only original spare parts may be installed.
9.1

Screw connections

♦ To prevent leaks, a regular check of the connec-
tion screws make in line with the operating re-
quirements.
For tightening torques, see Section 1.3.
♦ To prevent screw connections from becoming
loose in the event of pressure fluctuations or plant
vibrations, we recommend the installation of ex-
pansion joints or pulsation dampers.
9.2

Cleaning

Prior to starting any repair work, the valve is
to be thoroughly cleaned. Even if the valve
has been properly emptied and rinsed,
residual medium may still be found in the
valve, e.g. between the lining and body or in
the bonnet.
Plastic parts may absorb medium which gradually
emerges from the material after cleaning.
Wear the prescribed protective clothing!
Overflow valves which have been cleaned with water
or other media must be dried before re-assembly of
the parts and installation of the valve in the plant.
9530-020-en Revision 15
TM 10477 Edition 05/2022
9.3 Modification of the overflow
valve
If modifications to the valve are required, the
manufacturer must always be consulted.
Examples: Modification with changed test pressure,
replacement of the spring or adaption to the mass flow
by reducing the travel.
After approval by
modifications can be performed either by the
manufacturer or by the customer under the guidance
of a technical supervisory agency or any other
approval authority.
9.4 Adjustment of the test pres-
sure
♦ Undo locking plate 539, dismantle lifting lever 238
and unscrew the lifting cap 535.
♦ Undo nut 920/3.
♦ Adjust the spring tension with the adjusting screw
538 to the specified test pressure.
♦ Counter adjusting screw 538 with a hex. thin nut
920/3 resp. with centering nut 555 (DN 25).
♦ Check test pressure.
♦ Screw on lifting cap 535 and tighten.
♦ Insert lifting lever 238.
♦ Mount locking plate 539.
♦ Have valve lead-sealed.
♦ The data specified in the test certificates are to be
observed.
9.5 Important notes on disman-
tling / installation
First relieve the plug 204!
♦ Then undo the screws between the bonnet 513
and body 100.
♦ The seat and plug could otherwise be destroyed.
Read the precise instructions in Section 9.6.
♦ Always replace the seat and plug pairwise and
always rework them completely.
♦ Reworking of the seat and plug requires special-
ised knowledge.
♦ It is therefore recommended to have this work
carried out by the manufacturer.
♦ After dismantling, check all parts for wear and
damage.
♦ Observe sectional drawings in Section 10.
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the manufacturer, these