Flowserve LR Worthington User Manual
Page 17

LR, LRV, LLR and LR-S USER INSTRUCTIONS ENGLISH 71569088 08-10
Page 17 of 48
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4.6.4 Discharge piping 
See section 4.6.2 for typical pipework design. 
 
A non-return valve should be located in the discharge 
pipework to protect the pump from excessive back 
pressure and hence reverse rotation when the unit is 
stopped. 
 
Pipework reducers should have a maximum total 
angle of divergence of 9 degrees. 
 
Fitting an isolation valve will allow easier maintenance. 
 
4.6.5 Auxiliary piping 
 
4.6.5.1 Drains 
Pipe pump casing drains and gland leakage to a 
convenient disposal point. 
 
4.6.5.2 Pumps fitted with packed gland 
When suction pressure is below ambient pressure it 
is necessary to feed the gland packing with liquid to 
provide lubrication and prevent the ingress of air. 
This is normally achieved with a supply from the 
pump discharge volute to the stuffing box. 
 
If the pumped liquid is dirty and cannot be used for 
sealing, a separate clean compatible liquid supply to 
the gland at 1 bar (15 psi) above suction pressure is 
recommended. 
 
4.6.5.3 Pumps fitted with mechanical seals 
Single seals requiring re-circulation will normally be 
provided with the auxiliary piping from pump casing 
already fitted. 
 
If the seal requires an auxiliary quench then a 
connection must be made to a suitable source of 
liquid flow, low pressure steam or static pressure from 
a header tank. Recommended pressure is 0.35 bar 
(5 psi) or less. Check General arrangement drawing. 
 
Special seals may require different auxiliary piping to 
that described above. Consult separate User 
Instructions and or Flowserve if unsure of correct 
method or arrangement. 
 
For pumping hot liquids, to avoid seal damage, it is 
recommended that any external flush/cooling supply 
be continued after stopping the pump. 
 
4.6.6 Final checks 
Check the tightness of all bolts in the suction and 
discharge pipework. Check also the tightness of all 
foundation bolts. 
4.7 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. 
 
4.8 Electrical connections
Electrical connections must be made by
a qualified Electrician in accordance with relevant 
local, national and international regulations. 
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. 
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. 
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. 
A device to provide emergency stopping must be
fitted. 
 
If not supplied pre-wired to the pump unit, the 
controller/starter electrical details will also be supplied 
within the controller/starter. 
 
For electrical details on pump sets with controllers 
see the separate wiring diagram. 
See section 5.3, Direction of rotation,
before connecting the motor to the electrical supply. 
 
4.9 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. 
