Multitech 1777.8/7-10 G3 - Manual (Page 14)

Caution
Multitec
14
7 Servicing / maintenance
7.1 General instructions
The operator is responsible for ensuring that all maintenance,
inspection and installation work be performed by authorized,
qualified personnel who are thoroughly familiar with the
manual.
A regular maintenance schedule will help avoid expensive
repairs and contribute to trouble-free, reliable operation of the
pump with a minimum of maintenance expenditure and work.
Before commencing any work on the unit, always
make sure that the drive unit (electric motor, turbine,
I.C. engine, ...) cannot be started up.
Pumps handling liquids posing health hazards must
be decontaminated. When draining the fluid pumped
see to it that there is no risk to persons or the environment.
All relevant laws must be heeded.
7.2 Servicing / Inspection
7.2.1 Supervision of operation
The pump must run quietly and free from
vibrations at all times.
The pump must never be allowed to run dry.
Max. permissible room temperature 40 °C.
The bearing temperature may exceed room temperature by up
to 50 °C, but must never rise above 90 °C (measured on the
outside of the bearing bracket), see also section 7.4.4.1.
Do not run the pump against a closed shut-off valve for
prolonged periods of time so as to avoid heating up of the
fluid pumped.
Caution: For required minimum flows please refer to section
6.2.3.
During pump operation the shut-off valve in the suction
line must not be closed.
The mechanical seal shows only slight or invisible (vapour)
leakage during operation. It is maintenance-free.
Gland packings must leak slightly (individual drops).
Any stand-by pumps installed shall be switched on and then
immediately off again once a week to keep them operational.
Attention shall be paid to the correct functioning of the auxiliary
connections.
7.2.2 Bearings and lubrication
On grease-lubricated units, the rolling element bearings of the
MTC32 and the non-drive end rolling element bearings of the
MTC50 and MTC65 in design C and D are lubricated for life and
do not require re-lubrication. For this reason, no lubricating nip-
ples are provided on the bearing brackets.
Pump
Depending on the pump version, the rolling element bearings
are either grease-lubricated or oil-lubricated.
Grease quality / Grease change
The bearings are packed with high-quality lithium-soap grease.
Depending on the size and the operating hours of the pump, the
rolling element bearings must be re-lubricated or the grease in
the rolling element bearings must be replaced.
Speed (1/min)
Size MTC < 1800 » 2950 » 3550
32-50-65 10000h 7200h 5700h
100-125 9000h 5700h 3900h
150 8300h 4000h 3100h
If re-lubrication intervals are short, we recommend to
completely replace the grease once a year. If this is not the
case, the grease fill must be replaced completely at least every
two years. For this purpose, the rolling element bearings must
be removed, cleaned and packed with new grease.
Under unfavourable operating conditions, e.g. high ambient
temperature, high atmospheric humidity, dust-laden air,
aggressive industrial atmosphere etc., the bearings shall be
checked earlier and cleaned and packed with new grease, if
required.
Use a high-quality lithium-soap grease, free of resin and acid,
not liable to crumble and with good rust-preventive
characteristics. The grease should have a penetration number
(NLGI class) between 2 and 3, corresponding to a worked
penetration between 220 and 295 mm/10. Its drop point must
not be below 175°C. The bearing cavities must only be
half-filled with grease.
If required, the bearings may be lubricated with greases of other
soap bases. Since greases of differing soap bases must not be
mixed, the bearings must be thoroughly cleaned beforehand.
The re-lubrication intervals required must then be adjusted to
the greases used.