Flowserve BP User Manual
Page 7

BP USER INSTRUCTIONS ENGLISH 85392725 10-09 (E)
Page 7 of 44
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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 IIC 135 ºC (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)
Gas Group (Equipment Category 2 only) 
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. 
 
The temperature rise at the seals and bearings and 
due to the minimum permitted flow rate is taken into 
account in the temperatures stated. 
Temperature
class to
EN13463-1
Maximum
surface
temperature
permitted
Temperature limit of liquid
handled (* depending on
material and construction
variant - check which is lower)
T6 
T5 
T4 
T3 
T2 
T1 
85 °C (185 °F)
100 °C (212 °F) 
135 °C (275 °F) 
200 °C (392 °F) 
300 °C (572 °F) 
450 °C (842 °F) 
Consult Flowserve 
Consult Flowserve 
115 °C (239 °F) * 
180 °C (356 °F) * 
275 °C (527 °F) * 
400 °C (752 °F) * 
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 when the pump is required to be 
used in differently classified potentially explosive 
atmospheres. In this case the user is responsible for 
ensuring that the pump surface temperature does not 
exceed that permitted in its actual installed location. 
 
Do not attempt to check the direction of rotation with the 
coupling element/pins fitted due to the risk of severe 
contact between rotating and stationary components. 
 
Where there is any risk of the pump being run against a 
closed valve generating high liquid and casing external 
surface temperatures it is recommended that users fit 
an external surface temperature protection device. 
 
Avoid mechanical, hydraulic or electrical overload by 
using motor overload trips, temperature monitor or a 
power monitor and make routine vibration monitoring 
checks. 
 
In dirty or dusty environments, regular checks must 
be made and dirt removed from areas around close 
clearances, bearing housings and motors. 
 
1.6.4.4 
Preventing the build up of explosive 
mixtures 
ENSURE THE PUMP IS PROPERLY FILLED
AND VENTED AND DOES NOT RUN DRY 
 
Ensure the pump and relevant suction and discharge 
pipeline system is totally filled with liquid at all times 
during the pump operation, so that an explosive 
atmosphere is prevented. In addition it is essential to 
make sure that seal chambers, auxiliary shaft seal 
systems and any heating and cooling systems are 
properly filled. 
 
If the operation of the system cannot avoid this 
condition the fitting of an appropriate dry run 
protection device is recommended (for example liquid 
detection or a power monitor). 
