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Temperature class of the
centrifugal pump
T3
T4
The user must check that the minimum ignition temperature of the flammable substances present or pumped is:
-
For pumps marked T4: Higher than 135°C for flammable gases and vapours or temperature class T4, T3, T2 or
T1.
-
For pump with T3 marking: Over 200°C for flammable gases and vapours or temperature class T3, T2 or T1.
For ESN-EX or ESH-EX pumps with marking for areas with combustible dust, the user must observe the following safety
margins, specified in EN 1127-1 and EN 60079-14, with regard to the minimum cloud (TMIN) and layer (TMIC) ignition
temperatures of the substances that may be present:
(2/3 × TMI
) ≥ Temperature marking in °C of the centrifugal pump.
Nube
(TMI
- 75K) ≥ Temperature marking in °C of the centrifugal pump.
Capa
Therefore, the powdery substances present must have a self-ignition temperature:
-
For pumps marked T4 or T135°C: greater than 203°C in a cloud and 210°C in a layer.
-
For pumps with T3 or T200°C markings: over 300°C in a cloud and 270°C in a layer.
The manufacturer does not guarantee the safety of the ESN-EX or ESH-EX centrifugal pump against the risk of an
explosive atmosphere if the instructions given in this manual are not strictly observed.
1.3.2.2. Operation
The centrifugal pumps have been assessed and are ignition safe to operate in a zone classified as ZONE 1 and ZONE 2
for flammable gases/vapours (IIA and IIB) and as ZONE 21 and ZONE 22 for combustible dust (IIIA, IIIB and IIIC). Also to
operate with flammable liquids (IIA or IIB) indoors, under the conditions defined for ZONE 1 in internal parts. (*)
(*) The following definitions apply (Directive 1999/92/EC):
- "ZONE 1" as "working area in which an explosive atmosphere consisting of a mixture with air of flammable substances
in the form of gas, vapour or mist is likely to occur in normal operation occasionally".
- "ZONE 2" means a "place in which an explosive atmosphere consisting of a mixture with air of flammable substances
in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short
period only".
- "ZONE 21" as "working area in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely
to occur occasionally in normal operation".
- "ZONE 22" as a "place of work in which an explosive atmosphere in the form of a cloud of combustible dust in air is not
likely to occur in normal operation or, if it does occur, will persist for a short period only".
Centrifugal pumps must always be primed, with liquid inside by submerging the impeller. The user must ensure this by
the method he considers most appropriate.
The user of the pump must ensure that the pump does not operate against a closed outlet
The pump must be installed and operated in a horizontal position.
In the case of pumps with oil-lubricated bearings, the oil level in the bearing housing must be visible through the built-in
sight glass.
Maximum surface
temperature
200ºC
135ºC
Table 1
6
Maximum fluid temperature
180ºC
110ºC
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