Flowserve VF User Manual

Page 7

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VF USER INSTRUCTIONS ENGLISH 71561233 - 11/09

Page 7 de 32

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 °C (104 °F); 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, bearings and due
to the minimum permitted flow rate is taken into
account in the temperatures stated.

Temperature

class to

prEN 13463-1

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 the pump could be
installed in different hazardous atmospheres. In this
case the user is responsible for ensuring that the
pump surface temperature does not exceed that
permitted in the particular hazardous atmosphere.

If an explosive atmosphere exists during the
installation, do not attempt to check the direction of
rotation by starting the pump unfilled. Even a short
run time may give a high temperature resulting from
contact between rotating and stationary
components. Furthermore, confinement of liquid in
the pump and pipes must be avoided (valve closed).
If the liquid heats up this may cause excessive
pressure and lead to bursting of pump 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 PUMP IS PROPERLY FILLED AND

VENTED AND DOES NOT RUN DRY.

Ensure 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 (eg liquid
detection or power monitor).

To avoid potential hazards from fugitive emissions of
vapour or gas to atmosphere the surrounding area
must be well ventilated.

1.6.4.5 Preventing sparks

To prevent a potential hazard from mechanical

contact, the coupling guard must be non-sparking.

To avoid the potential hazard from random induced
current generating a spark the ground contact on the
baseplate must be used.

Avoid electrostatic charge: do not rub non-

metallic surfaces with a dry cloth, ensure cloth is
damp.

Where applicable the coupling must be selected to
comply with 94/9/EC and correct alignment must be
maintained.

Additional requirements for metallic pumps on
non-metallic baseplates.

When metallic components are fitted on a non-
metallic baseplate they must be individually earthed
(grounded).

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