NSWV 200, 250 & 300
VERTICAL DRY PIT SOLIDS-HANDLING PUMP SPECIFICATIONS
PART 1. GENERAL
1.01
This specification covers vertical, single stage, end suction, centrifugal pumps specifically
for municipal, institutional, commercial, and industrial sewage applications. Pumps will be
FLYGT as manufactured by Xylem Water Solutions with a maximum ___” diameter
suction and ___” diameter discharge. Each unit shall be furnished with a pump, base,
coupling, coupling guard and driver.
1.02
QUALITY ASSURANCE
A. All pumping equipment furnished under this Section shall be of a design and
manufacture that has been used in similar applications, and it shall be demonstrated
to the satisfaction of the Owner that the quality is equal to equipment made by that
manufacturer specifically named herein.
B. Unit responsibility. Pump(s), complete with motor, base, coupling, necessary guards
and all other specified accessories and appurtenances shall be furnished by the pump
manufacturer to insure compatibility and integrity of the individual components, and
provide the specified warranty for all components.
C. The vertical dry-pit solids-handling pump(s) specified in this section shall be furnished
by and be the product of one manufacturer.
D. Pumps are to be engineered and manufactured under a written Quality Assurance
program. The Quality Assurance program is to be in effect for at least ten years, to
include a written record of periodic internal and external audits to confirm compliance
with such program.
E. Pump(s) are to be manufactured under the certification of ISO-9001:2000.
1.03
PERFORMANCE
A. The pump(s) shall be designed for and operated continuously under normal service.
B. Operation Criteria:
Flow
(GPM)
TDH
(ft.)
Max.
Pump
Speed
(RPM)
Max.
Solids
Passage
Max.
Shutoff
Head (ft.)
NPSHR @
Rated
Condition
(ft.)
Design Condition
Secondary Condition
C. NPSH available at the centerline of the pump impeller is ___ feet at ______ GPM.
D. Pumped liquid is _______ with a maximum temperature of ___ deg. F.
PART 2, PRODUCTS
2.01
Rev. 2/16/15
PUMPS
A. Manufacturers
1. Pump(s) shall be the product of Xylem Water Solutions.
2. Manufacturer shall have installations of like or similar application with a minimum
of 40 years service for this pump size.
B. Design
1. Rotation
a. The pump will be (clockwise)(counterclockwise) rotation when looking at the
pump from the drive end.
2. Impeller
a. The impeller shall be single-suction enclosed type with two vanes, made of
close grained 2-3% Ni Cast Iron. Impeller be specifically designed with smooth
water passages to prevent clogging by stringy or fibrous materials, and shall
be capable of passing solids having a maximum sphere size of ____ inches.
b. The impeller shall be dynamically balanced, taper bored and keyed to the shaft
by a 18-8 stainless steel nut locked in place. It shall be readily removed without
the use of special tools.
3. Casing
a. The casing shall be close-grained cast iron conforming to ASTM A48 Class 30
of sufficient strength, weight and metal thickness to insure long life, accurate
alignment, and reliable operation. The volute shall have smooth fluid passages
large enough at all points to pass any size solid which can pass through the
impeller and provide smooth unobstructed flow.
b. The casing shall be flanged tangential discharge and capable of rotation in 45
degree increments to accommodate piping orientation.
c. Casing shall be split perpendicular to the shaft, with removable suction cover
and stuffing box cover. Machined fit for these parts shall be accurately aligned
and identical so that casing may be installed for either clockwise or
counterclockwise direction of rotation.
d. The casing shall be furnished with large cleanout openings located at the
impeller centerline, to allow access to the impeller. Priming, drain and ½”
minimum gauge connections shall be provided. Flanges shall be 125 lbs. flat
faced flanges per ANSI drilling and slotted for ease of assembly and
disassembly.
e. The casing shall be designed to permit the removal of the rotating assembly
without disturbing the suction or discharge piping. The casing shall be
hydrostatically tested to 1.5 times the design head or 1.25 times the shutoff
head whichever is greater.
f. Casing Connections: discharge flange shall be ANSI 125 lb. flat faced. Each
discharge nozzle shall be drilled and tapped with two 1.0” IPS taps, one on
either side. One of the taps in the discharge nozzle shall serve as a vent.
g. Discharge Position: pump discharge nozzle shall be capable of rotating to any
one of five discharge positions for each direction of rotation. For this
application the discharge will be located__________________________.
4. Wear Rings
a. Wear rings shall be provided on both the impeller and suction cover so that
clearances can be maintained throughout the life of the rings and minimize
recirculation.
b. Impeller wear rings shall be replaceable 11.5-14% chrome steel “L” shaped
axial or face-type and mounted on impeller to provide a renewable surface
opposite the suction cover wear plate.
Rev. 2/16/15
c. Suction cover wear rings shall be replaceable 11.5-14% chrome steel and
provide a minimum of ¼ inch wear surface. It shall be installed with its wear
surface parallel to the end of the impeller nut.
d. Wear rings shall be attached to the impeller and suction cover using an
interference fit and loctite.
e. Wear ring clearance adjustment shall be have provisions for adjustment of
axial clearance. This adjustment shall be made through the use of shims
placed between the frame and outboard bearing housing.
5. Suction Cover
a. The Suction Cover shall be removable to allow access to the impeller. It shall
be ASTM A48 Class 30 Cast Iron and drilled for ANSI 125 lb. flanges. The
mounting holes shall be slotted for ease of assembly and disassembly.
b. Suction gauge connections shall be drilled & tapped next to the suction flange
to accommodate a ¼ inch IPS pipe fitting.
c. Clean-out Port: a large clean-out opening shall be provided in the suction
nozzle. It shall have a removable cover to allow access to the suction for
inspection and flushing, if required.
d. Suction Flange: the suction flange shall be ANSI 125 lb. flat faced and slotted
for ease of assembly and disassembly.
6. Stuffing Box Cover and Stuffing Box
a. Stuffing box cover shall be made of ASTM A48 Class 30 close-grained cast
iron with integral stuffing box and shall be designed to accept either packing or
mechanical seal
b. Packing: stuffing box shall consist of five (5) rings of graphite-impregnated
packing, a Teflon seal cage, and a split-type gland to permit easy removal and
access to packing. Sealing liquid connection to stuffing box shall be tapped in
a convenient location.
c. Mechanical Seal: A John Crane double mechanical seal or equal shall be
installed in the stuffing box.
d. Dynamic seal: stuffing box shall be fitted with a single stage, Dynamic Seal
capable of balancing our positive suction heads.
1) Throttle Bushing: a throttle bushing and sleeve shall be placed in the stuff
box cover. Both pieces shall be made of 316 stainless steel with a NI-CRBoron coating to a hardness of 58-63 RC (approximately 650 BHN).
2) The Dynamic Seal expeller shall be made of nodular iron, ASTM 536 or
304 stainless steel. A pressure relief connection with elbow, fittings, and
tubing shall be provided in the seal cover to bleed liquid back to the suction
cover of the pump.
3) Static Seal: Dual static seals, provided with the grease cavity between
them, shall be installed in the seal cover to prevent leakage along the shaft,
when the pump is not running. A positive means for adding grease shall be
provided in the seal cover. Seals shall contact a 316 stainless steel sleeve
with a Ni-Cr-Boron coating to a harness of 58-63 RC (approximately 650
BHN). Equiseal® Dynamic Seal shall be manufactured by ITT WWW or
approved equal. Cartridge type double mechanical seal may be provided in
lieu of the Equiseal® specified, in such a case, one spare cartridge seal is
to be provided per pump, plus an adequately sized seal water system
capable of handling all pumps.
Rev. 2/16/15
7. Bearing Frame Assembly
a. The Bearing housing shall be one-piece rigid cast iron construction. Frame
shall be provided with cast iron bearing housing at the outboard end, and a
cast iron end cover at the inboard end. Both ends of the frame shall be
provided with lip type grease seals and labyrinth type deflectors to prevent the
entrance of contaminants.
b. Bearing frame shall be designed so that complete rotating assembly can be
removed from the casing without disconnecting suction or discharge piping.
c. Frame shall be provided with a ¾ inch IPS pipe tapped hole, located as low as
possible to drain the leakage from the packing gland.
d. Jacking bolts for external impeller adjustments are required.
e. Zerk-type grease fittings for bearing lubrication shall be supplied at the
bearing housing.
f. The pump shaft shall be high-strength carbon steel, AISI #4140 minimum,
accurately machined, tapered at the impeller end and sufficiently sized to
transmit full driver output. It shall be protected from the pumped liquid by a
shaft sleeve in the stuffing box area. A seal shall be provided, by a synthetic
rubber “O” ring, between the shaft and shaft sleeve to prevent leakage of
pumped liquid out and/or air into the pump.
g. Shaft sleeve for Packing: a renewable shaft sleeve used with packing shall be
of a corrosion resistant 400 series stainless steel with 500 Brinell hardness.
The sleeve provided shall extend through the stuffing box and under the gland.
h. Shaft sleeve for Mechanical seal: a renewable shaft sleeve used for
mechanical seals shall be 300 series stainless steel. positive adhesive sealed
to prevent leakage between the shaft and the sleeve, shall protect the shaft
through the sealing box area. The sleeve provided shall extend through the
stuffing box and under the gland.
i. Inboard bearing – inboard bearings shall be single row, radial type suitable for
all loads encountered in the service conditions.
j. Outboard bearing – outboard bearings shall be axial thrust, angular contact,
double row ball suitable for thrust loads in two directions.
k. Bearings: bearings shall be designed for 20,000 hours minimum life at 50%
B.E.P. Radial inboard bearing shall be roller type for F8-J, F8-H, F8-F frames
and deep groove ball for F8-G frame. They shall be suitable for all loads
encountered in the service conditions. Axial thrust outboard bearing shall be
deep groove angular contact double row or duplex type for F8-G and F8-H
frames. F8-J and F8-F frames shall have an outboard bearing arrangement
consisting of one deep groove ball bearing to take the radial loads and one
angular contact to take the axial loads.
l. Bearing Lubrication: bearings shall be grease lubricated with provisions for the
addition and relief of grease.
m. Bearing Locking: the outboard bearing shall be locked to the shaft with a nut
and lock washer. The lock washer shall have a key seat tab on its ID to prevent
it from turning and a set of tabs on its OD, one of which will align with a notch
in the nut to prevent it from loosening.
8. Pedestal Base, Suction Elbows, Coupling and Coupling Guard
a. Model 200 Pedestal Base: Pump shall be supported by either a cast iron
suction head with clean-out handhole. Base shall be designed to support the
Rev. 2/16/15
b.
c.
d.
e.
f.
g.
weight of (the pump and shafting)(the pump, motor support and motor). Base
shall safely withstand all stresses imposed thereon by vibration, shock and all
possible direct and eccentric loads. Base shall have adequate horizontal
dimensions, foundation contact area, anchorage facilities and shall be
sufficient height so the suction elbow will not touch the floor or foundation upon
which the pump is mounted.
Model 250 with intermediate shafting: Intermediate line shafting of the flexible
type shall be of the size (diameter, length, number of and joint) as
recommended by the shaft manufacturer to provide continuous 24hr duty at
any speed within the range specified and max. torque. Couplings shall be
universal joint type to permit removal of the pump rotating element without
dismantling other sections of shafting, any intermediate bearing, and without
removing driver. One slip spline, to allow for endwise movement, and the
necessary steady bearings shall also be provided for each shaft
Model 300 with direct-coupled motor: Pump shall be provided with a fabricated
steel motor support of sufficient size and strength to support the motor required
by the pump. The motor mounting surface shall be designed for a standard
NEMA “P” flange and designed to permit access to the frame and flexible
coupling.
Suction Elbow: Each pump shall be provided with a clean-out type cast iron
(non-reducing)(reducing) suction elbow which is bolted directly to the pump
suction flange. A 4 inch minimum handhole clean-out shall be provided with a
removable cover. The inner surface shall generally conform to the curvature
and radius of the suction elbow. A ¼ inch tapped hole for gauge connection
shall be provided in the elbow near the suction flange. A 2 inch tapped hole
shall be provided in the side of the elbow for use in applying water pressure to
unclog the pump in case of blockage.
Coupling: Couplings shall be of the manufacturer’s choice and of flexible type.
Coupling hubs shall be secured to the driver and driven shafts by a set screw
located over the key.
Coupling Guard: Guard shall be all-metal completely enclosing the coupling.
The coupling shall be a standard-flexible type and secured to the driver and
driven shafts by a setscrew located over the keyway.
9. Fits and Hardware
a. The volute/casing, suction cover, stuffing box cover, and frame shall be
manufactured with concentric shoulder fits to assure accurate alignment. All
machined bolts, nuts, and capscrews shall be of the hex-head type and will not
require the use of any special tools
10. Paint
a. Prior to paint: blast and clean per SSPC-SP10
b. Primer: primer paint with one coat of ICI Devoe Bar-Rust 233H for a DFT or 46 mils.
c. Top Coat: Apply top coat with ICI Devoe Bar-Rust 235 Epoxy for a DFT of 4 to
8 mils
d. Color Custom Grey. Total DFT of 8 to 16 mils
11. Vibration Limitations (Field)
Rev. 2/16/15
a. The limits of vibration as set forth in the standards of the Hydraulic Institute
shall govern.
12. Testing
a. A certified factory performance test shall be performed on each pumping unit in
accordance with Hydraulic Institute Standards, latest edition. Tests shall be
sufficient to determine the curves of head, input horsepower, and efficiency
relative to capacity from shutoff to 150% of design flow. A minimum of six
points, including shutoff, shall be taken for each test. At least one point of the
six shall be taken as near as possible to each specified condition.
Rev. 2/16/15