Flowserve Twin Screw Rotary - Manual (Page 28)

TWIN SCREW PUMPS. ORIGINAL USER INSTRUCTIONS. ENGLISH. 71569243 – 07/10
Page 25 of 53
®
4.8 Pressure gauges
It is recommended that suitable suction and discharge
pressure gauges be provided. Pressure readings are
essential to resolving operational problems and are
useful for monitoring pump performance.
4.9 Final shaft alignment check
After connecting piping to the pump, rotate the shaft
several times by hand to ensure there is no binding
and all parts are free.
Recheck the coupling alignment, as previously
described, to ensure no pipe strain. If pipe strain
exists, correct piping.
4.10 Electrical connections
4.10.1 Electrical connections must be
made by a qualified Electrician in accordance with
relevant local national and international regulations.
4.10.2 It is important to be aware of the
EUROPEAN DIRECTIVE on potentially explosive
areas where compliance with IEC60079-14 is an
additional requirement for making electrical
connections.
4.10.3 It is important to be aware of the
EUROPEAN DIRECTIVE on electromagnetic
compatibility when wiring up and installing equipment
on site. Attention must be paid to ensure that the
techniques used during wiring/installation do not
increase electromagnetic emissions or decrease the
electromagnetic immunity of the equipment, wiring or
any connected devices. If in any doubt contact
Flowserve for advice.
4.10.4 The motor must be wired up in
accordance with the motor manufacturer's instructions
(normally supplied within the terminal box) including
any temperature, earth leakage, current and other
protective devices as appropriate. The identification
nameplate should be checked to ensure the power
supply is appropriate.
4.10.5 A device to provide emergency stopping
must be fitted.
4.10.6 If not supplied pre-wired to the pump unit, the
controller/starter electrical details will also be supplied
within the controller/starter.
4.10.7 For electrical details on pump sets with
controllers see the separate wiring diagram.
4.10.8 See section 5.3 Direction of
rotation before connecting the motor to the electrical
supply.
4.11 Protection systems
The following protection systems are
recommended particularly if the pump is installed in a
potentially explosive area or is handling a hazardous
liquid. If in doubt consult Flowserve.
If there is any possibility of the system allowing the
pump to run against a closed valve or below minimum
continuous safe flow a protection device should be
installed to ensure the temperature of the liquid does
not rise to an unsafe level.
If there are any circumstances in which the system
can allow the pump to run dry, or start up empty, a
power monitor should be fitted to stop the pump or
prevent it from being started. This is particularly
relevant if the pump is handling a flammable liquid.
If leakage of product from the pump or its associated
sealing system can cause a hazard it is recommended
that an appropriate leakage detection system is
installed.
To prevent excessive surface temperatures at
bearings it is recommended that temperature or
vibration monitoring are carried out. See sections
5.9.4 Bearings and 5.9.5 Normal vibration levels,
alarm and trip.
The user should review the need for special operating
procedures and protective devices peculiar to the
particular installation involved. These may include
special start-up and shut-down procedures, over-
speed protection, temperature, flow and pressure
interlocks, protection against automatic start-up in the
event of power failure, surge protection, protection
from freezing, lack of prime protection, temporary
strainers in the suction line, vacuum breakers, etc.
Great care should be exercised during the erection of
piping to keep lines clean and free of dirt, scale,
threading or welding chips, etc. Such foreign matter
entering the pump may cause scoring of the body
bores and unnecessary breakdown and costly repairs.
For pumps having jacketed bodies, the jacket inlet
piping should always be made at the lowest inlet point
with the outlet at the top or highest point and the
opposite configuration when using a gaseous heat
transfer media. Provide a valve on the inlet piping so
that flow may be regulated to control temperature.