Xylem NPOPTM NPO Product Training Manual - Manual (Page 7)

PAGE 7
Commercial Water
Goulds Water Technology
MAJOR COMPONENTS
CASING: The NPO casing is 316L stainless steel with 1¼”, 1½” or 2” suction and 1”, 1¼” or 1½” discharge. Connec-
tions are centerline NPT threaded. The inner flat running surface matches the maximum impeller diameter. Vent/
prime and drain connections are fitted with stainless steel plugs.
SEAL HOUSING: The NPO seal housing is the same as that used for the NPE. It is made of 316L stainless and fea-
tures a series of formed barriers designed to keep the liquid circulating and reduce the chance of heat build up in
the seal area. The seal stationary seat fits into the opening. The seal housing also positions the casing o-ring against
the casing rim.
SEALS: John Crane, Type 21, 5 ⁄
8
” seals are used in the NPO. The standard seal is carbon/silicon-carbide/viton. Op-
tional faces are silicon-carbide vs. silicon-carbide. Optional elastomer is EPR. Metal parts are all 316 stainless steel.
Seals are interchangeable with the NPE. Casing o-rings are available to match seal elastomer options.
IMPELLER: The NPO impeller uses a semi-open design, with no front shroud. This type of impeller is capable of
passing up to
3 ⁄
8
” solids and is ideal for applications where food particles, lint, seeds or other small solids and par-
ticles are likely to be found in the pumpage. The NPO impeller is 316 stainless steel for maximum service life. It is
threaded to fit 56J motor shafts and is supplied with a front lock nut.
MOTOR ADAPTER: The NPO is supplied as standard, with a non-footed 316L stainless steel motor adapter. This
is the same motor adapter used on the frame mounted version of the NPE. This design was chosen to provide less
vibration and more mounting standardization through the use of welded motor mounting feet. Please note, how-
ever, that this version produces an interference fit, since the casing extends approximately 1
1 ⁄
8
” below the motor
feet. In most washing systems, the pump is mounted on framing inside the cabinet so that the liquid end is located
in open space. The footed NPE motor adapter with a non-footed motor can be ordered as an option if required.
MOTORS: The most common motor for the NPO is a single phase, ODP, 115/230 volt with a solid state switch. This
motor is available in ½ to 2 HP and is typical in most washer systems. In addition, those motors used for the ICS
including ODP, TEFC, Explosion Proof, 575 volt and three phase may also be used on the NPO. The use of NPE mo-
tors is also possible, but requires the use of the footed motor adapter.
VENT/FLUSH: The optional vent/seal flush for the NPE is also available on the NPO. This is particularly useful in
removing air bubbles which may form at the seal area during priming if the pump is mounted vertically.
FRAME MOUNTED: The NPO can be frame mounted if required by using the same bearing frame, baseplate,
coupling and T-frame motors used for the NPE.