13
OEG Pressure storage units DE / DZ
GB
• The filter insert and the O-ring of the filter cup have to be replaced at least once a year,
sometimes earlier depending on the dirt. Only use filter inserts with the same filter
mesh.
• The pre-charge pressure of the expansion vessel must be checked and complemented, if
necessary, every 3 months. It should be approx. 1.5 bar. For refilling the nitrogen
cushion, you may only use vessel filler (nitrogen).
• If, in exceptional cases, the replacement of parts is necessary, only original OEG spare
parts are allowed to be used. Otherwise, a flawless operation is not guaranteed and this
could cause damages.
The units operate with a diaphragm expansion vessel in welded version with oil-resistant
nitrile half-shell membrane according to the requirements of DIN4807. Cylindrical design,
permissible operating overpressure 6.0 bar.
• Before the installation, the pre-charge pressure must be controlled and adjusted if
required.
• Use a suitable sealant for sealing the vessel, preferably teflon tape.
• If the expansion vessel is secured with a clamping band or similar, it is absolutely
important that the connecting thread is not strained.
• Check and, if required, complement the pre-charge pressure every 3 months with an
unpressurised system.
• Use only vessel filler (nitrogen) for refilling the nitrogen cushion.
The diaphragm expansion vessel is exclusively used for pump control in a pressure storage
unit. It is not designed to intercept a potential thermal expansion. In this case, additional
precautions have to be taken (e.g. installation of another pressure expansion vessel or a
pressure-balancing valve).
A pressure loss of 10% within a quarter of a year is permissible and should be taken into
account at maintenance intervals. A diaphragm expansion vessel is a wear part due to the
continuous load of the membrane and has to be replaced if/when defective.
Maintenance and service
9.0
Special features of the
diaphragm expansion vessel
10.0