Flowserve N-Series Worthington - Manual (Page 5)

N-SERIES OF THRUST POT USER INSTRUCTIONS ENGLISH 07/14
Page 5 of 20
corresponding to the mass and in accordance with
current local regulations.
HOT AND COLD PARTS
If hot or freezing components or auxiliary heating
supplies can present a danger to operators, they
must
be shielded to avoid accidental contact. If
complete protection is not possible, the machine
access must be limited to maintenance staff only.
Bearing housings must not be insulated
and drive motors and bearings may be hot.
If the temperature is greater than 80 °C (175 °F) o r
below -5 °C (20 °F) in a restricted zone, or
exceeds local regulations, action as above shall
be taken.
1.6.4 Products used in potentially explosive
atmospheres
Measures are required to:
•
Avoid excess temperature
•
Prevent dry running
•
Prevent the generation of sparks
•
Maintain the pump to avoid hazard
The following instructions for pumps and pump units
when installed in potentially explosive atmospheres
must be followed to help ensure explosion protection.
For ATEX, both electrical and non-electrical equipment
must meet the requirements of European Directive
94/9/EC. Always observe the regional legal Ex
requirements eg Ex electrical items outside the EU may
be required certified to other than ATEX eg IECEx, UL.
1.6.4.1
Scope of compliance
Use equipment only in the zone for which it is
appropriate. Always check that the driver, drive
coupling assembly, seal and pump equipment are
suitably rated and/or certified for the classification of the
specific atmosphere in which they are to be installed.
1.6.4.2 Marking
An example of ATEX equipment marking is shown
below. The actual classification of the pump will be
engraved on the nameplate.
II 2 GD c IIC135ºC (T4)
Equipment Group
I = Mining
II = Non-mining
Category
2 or M2 = High level protection
3 = normal level of protection
Gas and/or Dust
G = Gas; D= Dust
c = Constructional safety
(in accordance with EN13463-5)
b = Control of ignition source
(in accordance with EN13463-6)
Gas Group
IIA – Propane (Typical)
IIB – Ethylene (Typical)
IIC – Hydrogen (Typical)
Maximum surface temperature (Temperature Class)
(see section 1.6.4.3)
1.6.4.3
Avoiding excessive surface
temperatures
ENSURE THE EQUIPMENT TEMPERATURE
CLASS IS SUITABLE FOR THE HAZARD ZONE
Pumps have a temperature class as stated in the
ATEX Ex rating on the nameplate. These are based
on a maximum ambient of 40 ºC (104 ºF); refer to
Flowserve for higher ambient temperatures.
The surface temperature on the pump is influenced
by the temperature of the liquid handled. The
maximum permissible liquid temperature depends on
the temperature class and must not exceed the
values in the table that follows.
Temperature class
to EN13463-1
Maximum surface
temperature permitted
Temperature limit of
liquid handled *
T6
T5 85 °C (185 °F)
100 °C (212 °F)
Consult Flowserve
Consult Flowserve
* The table only takes the ATEX temperature class into consideration.
Pump design or material, as well as component design or material,
may further limit the maximum working temperature of the liquid.
The temperature rise at the seals and bearings and
due to the minimum permitted flow rate is taken into
account in the temperatures stated.
The responsibility for compliance with the
specified maximum liquid temperature is with the
plant operator.
Temperature classification “Tx” is used when the
liquid temperature varies and the pump could be