Schwing SP 1800, Original Operating Instructions

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4.9 Pressure checks - stationary concrete pumps
Druckkontrolle-SP-EN.fm - 01.01.01 261
4.9 Pressure checks - stationary concrete pumps
All hydraulic consumers are secured by pressure relief valves (PRV).
These valves are set at the factory. Readjustment is as a rule only necessary after
replacement or repair of the hydraulic systems.
Regular pressure checks serve to detect errors early on. Carry out the checks while
the machine is running at operating temperature and speed.
WARNUNG!
Warning!
The factory-set pressures must not be altered. Settings may only be config-
ured by technically qualified workshop personnel!
• Only loosen hydraulic system connections if the drive is not running and the
pressure accumulator (if present) is relieved. This also applies to the assembly
and disassembly of test pressure gauges.
• After the pressure check, first switch off the concrete pump, then turn the ball
valve. This is to prevent an uncontrolled start-up of the concrete pump.
ACHTUNG!
Attention!
When checking the pressure of the concrete pump hydraulic system, be sure
to set the direction to “Pump”.
In the direction "Sucking", the seals of the concrete pump control block may be
pushed out.
4.9.1 Concrete pump system
The hydraulic pump of the concrete pump system is equipped with a "pressure cut-
off". This swivels the pump back before the maximum operating pressure set on the
pressure relief valve (PRV) is reached.
The pressure cut-off prevents the loss of performance and heating of oil which oc-
cur when hydraulic oil is discharged from the pressure relief valve.
The value displayed on the pressure gauge during the pressure test must be lower
than the setting on the pressure relief valve. See hydraulic switching diagram.
Appropriate settings are carried out on the hydraulic pump and pressure relief
valve.
If, during the check, the prescribed values are clearly exceeded or fallen short of,
leave the required setting adjustment work to SCHWING’s customer service.
Take the machine out of service and transmit the measured values to customer ser-
vice.