8. Installing the product
Warning
The pump must never run dry. Make sure that the
pump is filled with pumped liquid during operation.
Warning
The responsibility for checking the functions of the
dry-running protection, such as flow rate, sealing
pressure and temperature of the barrier or flushing
liquid rests with the installer/owner.
Warning
Increased leakage can be the indication of shaft seal
failure. For some types of liquids the leakage will not
be visible due to evaporation.
8.1 Pump with single seal
8.1.1 Non-flammable liquids
Category 2G/D
Make sure that the pump is filled with pumped liquid during
operation. If this is not possible, ensure appropriate monitoring,
e.g. dry-running protection to stop the pump in case of
malfunction.
Category 3G/D
No additional monitoring, dry-running protection, is required for
the pump system.
8.1.2 Flammable liquids, pump unit
Category 2G/D and 3G/D
Make sure that the pump is filled with pumped liquid during
operation. If this is not possible, ensure appropriate monitoring,
e.g. dry-running protection to stop the pump in case of
malfunction.
Ensure sufficient ventilation around the pump. The leakage rate
of shaft seal is less than 24 ml for each 24 hours of operation.
Ensure proper ventilation to maintain the zone classification
stated on the pump nameplate.
Category M2
Protect the pump by a guard to prevent damage from falling or
ejected objects.
8.2 Pump with MAGdrive
Warning
Always fill the pump with liquid and ensure that the
minimum flow is obtained.
See the CRN MAGdrive installation and operating instructions on
http://net.grundfos.com/qr/i/96464310.
8.3 Pump with double seal
Back-to-back or tandem
8.3.1 Non-flammable liquids, pump unit
Category 2G/D
Make sure that the pump is filled with pumped liquid during
operation. If this is not possible, ensure appropriate monitoring,
e.g. dry-running protection to stop the pump in case of
malfunction.
Category 3G/D
No additional monitoring, dry-running protection, is required for
the pump system.
6
8.3.2 Flammable liquids - pump unit
Category 2G/D and 3G/D
Make sure that the pump is filled with pumped liquid during
operation. If this is not possible, ensure appropriate monitoring,
e.g. dry-running protection to stop the pump in case of
malfunction. Ensure sufficient ventilation around the pump. The
leakage rate of a shaft seal is less than 24 ml for each 24 hours of
operation. Ensure proper ventilation to maintain the zone
classification stated on the pump nameplate.
Category M2
Protect the pump by a guard to prevent damage from falling or
ejected objects.
9. Operating conditions
9.1 Maximum liquid temperature
In normal pump operation the highest temperatures are to be
expected at the surface of the pump casing and at the shaft seal.
The surface temperature will normally follow the temperature of
the liquid. The temperature class (T1, T2, etc.) specifies the
maximum permissible temperature at the surface of the pump
during operation. See section
9.2 Temperature
9.2.1 Temperature
class. and fig. 2.
You can calculate the permissible liquid temperature by finding
the maximum surface temperature in the table in section
9.2.1 Temperature
class, e.g. T4 = 135 °C, and reduce T4 with
the temperature contribution for shaft seals. See fig. 2. Never
exceed the calculated liquid temperature.
Pumps that are allowed to pump liquids up to a maximum of 150
°C, are equipped with a tandem shaft seal. In this case, the
temperature and flow of the flushing liquid must be according to
the description in the installation and operating instructions "CR,
CRI, CRN - Double seal (tandem)".
Make sure that the combination of CR pump and dry-running
protection is described in the explosion protection document
according to the directive 1999/92/EC.
The responsibility for checking the correct flow and
the temperature of the flushing liquid rests with the
Note
installer or owner.
9.2 Temperature calculation
The illustration below shows the maximum surface temperature
of the pump as a result of the maximum liquid temperature and
temperature rise in the shaft seal.
Maximum surface temperature.
Fig. 2
Maximum surface temperature
Pos.
Figure legend
1
Maximum temperature of the pump
Temperature rise in the shaft seal. Calculated by
2
Grundfos. See section
3
Maximum liquid temperature
calculation,
1
2
3
9.2.1 Temperature
class.