Pump description, Configurations, Name nomenclature – Flowserve LNN User Manual
Page 11: Design of major parts, Configurations (3.1), Design of major parts (3.3), Name nomenclature (3.2), 3 pump description, 1 configurations, 2 name nomenclature
LNN, LNNV, LNNC USER INSTRUCTIONS ENGLISH 71569074 06-14
Page 11 of 56
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Make sure that hazardous substances are
disposed of safely and that the correct personal
protective equipment is used. The safety
specifications must be in accordance with the current
regulations at all times.
3 PUMP DESCRIPTION
3.1 Configurations
The LNN type pump is a single stage, double suction,
horizontal split volute type centrifugal pump designed
for water works, drainage, general service and
circulating applications. It can be used with motor,
steam turbine and gasoline or diesel engine drives.
The LNN can have the following configurations:
LNN horizontal suction and discharge nozzles (inline)
LNNC bottom vertical suction, horizontal discharge
LNNV horizontal suction/discharge, vertical shaft (inline)
There is also an advanced design designated LNNA.
3.2 Name nomenclature
The pump size will be engraved on the nameplate
typically as below:
400-LNNA-875-AA
Nominal discharge branch size
Configuration
– see 3.1 above
Nominal maximum impeller diameter
Impeller hydraulic type *
Casing hydraulic type *
(* Normally the hydraulic type will appear on the
performance curve.)
The typical nomenclature above is the general guide
to the LNN configuration description. Identify the
actual pump size and serial number from the pump
nameplate. Check that this agrees with the
applicable certification provided.
3.3 Design of major parts
3.3.1 Pump casing
The pump has its main casing gasket axial to the
shaft allowing maintenance to the rotating element by
removing the top half casing. Suction and discharge
branches are in the bottom half and therefore remain
undisturbed.
3.3.2 Impeller
The impeller is fully shrouded and may be fitted with
optional hub rings.
3.3.3 Shaft
The large diameter stiff shaft, mounted on bearings,
has a keyed drive end.
3.3.4 Pump bearings and lubrication
Ball bearings are fitted as standard and may be either
oil or grease lubricated, protected by V-ring seals.
Oil lubrication is only available where the pump shaft
is horizontal.
Bearing isolators or stationary labyrinths may be
fitted as an option in the bearing covers to protect the
bearings.
The LNNV as standard has a liquid lubricated journal
bearing fitted at the non-drive end. This bearing is
lubricated by pumped product or from an external
clean source. A grease lubricated ball bearing option
may be fitted at the non-drive end.