2 direction of flow and installation position, 3 test pressure, 4 grounding – Richter RSS/F Series Bellows-Sealed Control Valves User Manual

Page 12: 5 monitoring connection, 7 operation, 1 initial commissioning, 2 improper operation and their consequences, 3 shutdown, Direction of flow and installation position, Test pressure

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Series RSS/F

Page 12

9260-060-en

Revision 03

TM 7168

Edition 06/2008

6.2 Direction of flow and

installation position

Normally the valve is installed in a horizontal pipe with
the actuator on top. The valve can also be installed
with the actuator underneath.
However, this is only admissible if there is no risk of
contamination to the bellows, e.g. from the sedimenta-
tion of solids.
Inclined positions of the actuator are only admissible
after consultation with the manufacturer. In this case a
support structure may have to be provided for the
actuator.
The direction of flow is from below against the plug.
An arrow on the body indicates the direction of flow.

6.3 Test

pressure

The test pressure PT of an open valve must not
exceed the value of 1.5 x PN/PS as per the
identification of the valve.

6.4 Grounding

The valve must be grounded. The simplest solution is
to use tooth lock washers which are placed under one
pipe bolt of each flange.
At the customer's request a setscrew M6 with a hex.
nut and washer will be provided at each flange as an
additional grounding connection.

Otherwise grounding must be ensured by different
measures e.g. a cable link.

6.5 Monitoring

connection

If the cover flange has a screw-in fitting for an
alarm connection, the latter must also be
connected or the screw-in fitting has to be

sealed. Otherwise, medium could escape if the
bellows became defective.

In order to ensure leak monitoring, Richter recom-
mends the combination of the safety stuffing box with
a warning connection.

7

Operation

7.1 Initial

commissioning

Normally, the valves have been tested for leaks with
air or water. Prior to initial operation check cover
screws. For torques see Section 1.3.

Unless otherwise agreed, there could be
residual amounts of water in the flow section
of the valve; this could result in a possible
reaction with the medium.

To prevent leaks, all connection screws should be
retightened after the initial loading of the valve with
operating pressure and operating temperature. For
torques, see Section 1.3.

7.2 Improper operation and their

consequences

Crystallisation must be prevented, e.g. by heating.
In extreme cases this may cause blocking.
Operation with solids leads to increased wear.
Operating during cavitation leads to increased
wear.
Non-observance of the pressure-temperature
diagram can lead to damage.

If no monitoring is provided by the warning
connection, do not tighten safety stuffing box.
Otherwise any leak cannot be seen.
The valve is not to be operated in the wrong
direction of flow. Otherwise, it may close unintenti-
onally with an actuator of normal dimensions.

7.3 Shutdown

The local regulations are to be observed when
dismantling the valve.

Make sure that a remote-controlled actuator
cannot be switched on by accident.

In the case of a diaphragm actuator make sure that
there is no more compressed air in the actuator; the
springs must be in the unstressed state.
Before undoing the pipe or cover flange bolts, ensure
that the plant is depressurised on both sides of the
valve.

Prior to the start of maintenance work, the
valve must be thoroughly cleaned. Medium
residue may be in the valve even if it has

been properly drained and flushed. Drain the valve on
both sides.
After dismantling, immediately protect the valve
flanges against mechanical damage by using flange
caps. See also Section 6.1.

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