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Potential ignition source
Measures
Reference to
standards
considered
Normal
service
Trouble to be
expected
Hot surface
- Make sure that the max. permitted temperature is not
exceeded!
EN 13463-1
-
Hot surface
Make sure that the rotor, the pinion and the plain bearings are
properly lubricated.
Every precaution must be taken to prevent the pump running
dry!
EN 13463-1
5.2.; 6.1.2.
Mechanical
sparking
The materials employed are stainless steel or ductile cast iron.
These materials are permitted as set out in EN 13463-1. All
bearings are made of stainless steel.
Mechanical
sparking
Mechanical sparking which could ignite a potentially explosive
atmosphere is not considered as a trouble to be expected.
Faster-than-
normal heating
of the gland
packing
Lubrication of the packing rings must be ensured.
Temperature monitoring is essential – see Section 5.1
Faster-than-
normal heating
of shaft seals
and
mechanical
seals
Quenching and flushing liquid must be checked. Pump must
not be allowed to run dry!
Operating
Manual
Electrostatic charges
During normal service, while complying with the design
criteria, dangerous electrostatic charges which can result in
discharge sparks that could ignite a potentially explosive
atmosphere are ruled out as trouble to be expected since
Æthe thickness of a paint coat that may not be
electroconductive is less than 0.2 mm;
Æthere are no exposed components of non-conductive
plastics in pumps;
Æall conductive components of the pump are in metal-to-
metal contact to one another and the pump is included in
the equipotential bonding system of the equipment;
Æit needs to be remembered that a flexible coupling with non-
conductive elastoms functions as insulation.
Potential differentials between the individual assemblies
(pump and motor) are prevented in that all the assemblies
of the pump are bonded through metal-to-metal screwed joints
and, in the end, the pump is included in the equipotential
bonding system of the equipment (earthed). The oil film
between the rotating and the stationary components is not
considered a mutual insulation. However, it should be
remembered that a flexible coupling with non-conductive
elastomers between the motor and the drive shaft functions as
insulation.
EN 1127-1
6.4.7
EN 13463-1
7.4.1, 7.4.2,
7.4.4, 11
Ignition sources other than those described above are not likely to occur.
Therefore, no further evaluation of ignition hazards is required.
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