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Product information
Bosch Rexroth AG, DBA...1X/...E, RE 25880-B/10.18
5.2 Component marking
Type-examination tested safety valves bear a coded component marking. The
component marking always comprises the identical elements, the meaning of which
is shown in the following example:
Table 6: Example of component marking
TÜV.
SV.
__ ―
1150.
22.
F.
G.
p
Set response pressure in bar
Maximum admissible flow in l/min without
counter pressure in the discharge line
1)
Fluid
Smallest flow diameter in front of the valve seat in mm
Number of the component marking assigned by VdTÜV
Last digit of the year of the last extension of the validity of the component
marking
Safety valve
Mark of the notified body which has carried out the type-examination procedure
1)
The flow specified in the component marking can only be used in case of operation within the
identical pressure range (also when opening the valve using a directional valve attached to the
main stage), see
"Data sheet 25880"
.
5.3 Limitations of use
The safety valves may only be operated within certain limitations of use, see
"Data sheet 25880"
. The maximum admissible flow in l/min can always been seen
from the last but one figure of the component marking.
In the plant, the response pressure specified in the component marking is set
with a flow of 11 l/min.
The component marking is located on the name plate.
The maximum admissible flow stated in the component marking must not be
exceeded.
It applies to:
•
External
pilot oil return (=
Y
in the type code)
without counter pressure
in the
discharge line Y
, admissible counter pressure in the discharge line (port T)
< 10 bar
•
Internal
pilot oil return (= no code in the type code). The maximum admissible flow
is only admissible
without counter pressure
in the
discharge line
(port T).
With internal pilot oil return, the system pressure increases by the counter pressure
in the discharge line (port T) with increasing flow.
In this connection, observe the rules AD2000 - data sheet A2, point 6.3!
To ensure that this increase in system pressure caused by the flow does not exceed
10% of the set response pressure, the admissible flow has to be reduced dependent
on the counter pressure in the discharge line (port T) see
"Data sheet 25880"
.
