PUMPING EQUIPMENT: NON-CLOG CENTRIFUGAL

PUMPING EQUIPMENT:  NON-CLOG CENTRIFUGAL

PART 1 - GENERAL

1.1      SUMMARY

A.   Section Includes:

1.   Non-clog Centrifugal Pumps:    Furnish and  install  Vertical Non-Clog Flexible Coupled Dry Pit Pumping Units complete with all accessories and appurtenances as shown in the Plans and specified herein or as required for a complete operating system. Each Pumping Unit shall be rated for continuous duty in accordance with the operating conditions. Each unit shall be furnished with pump, motor, vertical pump/motor baseplate with flexible coupling and guard.

B.   Related Sections include but are not necessarily limited to:

1.   Division 01, Additional General Requirements

2.   Section 09800, Protective Coating.

3.   Section 11005, Equipment: Basic Requirements

4.   Section 11210, Pumps, General

5.   Section 16010, Electrical General Provisions

6.   Section 16220, Electric Motors

7.   Section 16418, Variable Frequency Drives Below 100 hp

8.   Section 16442, Control Panels

9.   Section 17300, Control Strategies

10. Division 17

1.2      QUALITY ASSURANCE

A.   Referenced Standards:

1.   American Bearing Manufacturers Association (ABMA)

2.   American Iron and Steel Institute (AISI):
a.   Steel Products Manual.

3.   American National Standards Institute (ANSI)

4.   ASTM International (ASTM):
a.   A48, Standard Specification for Gray Iron Castings
b.   A108, Standard Specification for Steel Bar, Carbon and Alloy, Cold Finished
c.   A276, Standard Specification for Stainless Steel Bars and Shapes
d. A278, Standard Specification for Gray Iron Castings for Pressure-Containing Parts for Temperatures Up to 650 degrees F
e.   A743, Standard Specification for Castings, Iron-Chromium, Iron-Chromium- Nickel, Corrosion Resistant, for General Application
f.    A744, Standard Specification for Castings, Iron-Chromium-Nickel, Corrosion
Resistant, for Severe Service

B.   The Pumping Units shall conform to all applicable requirements of ASTM, ANSI and Hydraulic Institute.  For purposes of this specification, the revision and/or version of the referenced standards in effect on the date of public bid opening shall apply.

C.  Qualification of the Manufacturer:

1.   The Pumping Units specified shall be the products of reputable manufacturers who have been regularly engaged in the design, manufacture and furnishing of Wastewater Pumping Equipment for at least ten (10) years.

2.   The horizontal dry-pit solids-handling pumps specified in this Section shall be furnished by and be the product of one manufacturer.

3.   Pump(s) are to be engineered and manufactured under the certification of ISO-
9001.

D.  WARRANTY

1.   The pumps and all components specified in this section shall be warranted by the manufacturer for a minimum three (3) year period after beneficial occupancy of the Work pursuant to “Use Prior to Final Completion” of the General Conditions, against defects in workmanship and materials.

1.3      SUBMITTALS

A.   Shop Drawings:

1.   The CONTRACTOR shall submit shop drawings showing fabrication, assembly, foundation, and installation details, along with detailed specifications and data covering materials of construction, devices, and other accessories forming a part of the equipment. The shop drawings shall be provided in accordance with this Section and  the  requirements of  Section  11005,  Equipment:    Basic  Requirements, and Section 11210, Pumps, General.

2.   Documentation:   The CONTRACTOR shall submit a letter confirming that all equipment is compatible with the intended service.

3.   The CONTRACTOR shall submit capacity, discharge pressure, horsepower and data on assembly, anchor bolts, and mounting.  The CONTRACTOR shall provide a letter from the pump manufacturer confirming compatibility between the pump motor and VFD being provided, as required in Section 16418, Variable Frequency Drives Below 100 hp.

4.   The CONTRACTOR shall submit motor data in accordance with Section 16220, Electric Motors.

5.   The CONTRACTOR shall submit catalogue cuts, wiring diagrams, and material data for all instrumentation associated with the pumps, as required in Division 17, Instrumentation and Control.

B.   Source Quality Control:

1.   Submit the following for approval:

a.   Source quality control test reports shall be submitted prior to shipping the pump.
b.   Certifications: Certification statement of solids passage.
c.   Certified pump performance curve.
d.   Pump head-discharge curve at minimum, maximum and two intermediate speeds with efficiency, horse power and NPSHR indicated for each speed. Pump head-discharge curve shall be provided for single pump operation as well as dual pumps in parallel operation.

PART 2 - PRODUCTS

2.1      ACCEPTABLE MANUFACTURERS

A.   Subject to compliance with the Contract Documents, the following manufacturers are acceptable:

1.   Non-clog centrifugal pumps:

a.   Fairbanks-Morse.
b.   Chicago.
c.   ITT Flygt A-C.
d.   Or Equal.

2.2      MATERIALS

A.   Pump volute:
1.   Cast iron, close-grained ASTM A48, Class 30.

B.   Impeller:
1.   Cast iron, close-grained ASTM A48, Class 30.

C.  Shaft:
1.   Stainless steel, AISI 416.

D.  Impeller W ear Rings: Stainless steel, AISI 416.

E.   Shaft Sleeve: Stainless steel, AISI 416.

F.   Stuffing Box, Gland Bolts and Nuts: 316 stainless steel.

G.  Seal Type: Chesterton 442 Split Seal.

H.  Frame: Cast iron, ASTM A48 Class 30.

I.    Bearing Housing: Cast iron, ASTM A48.

J.   Baseplate: Fabricated steel drip lip.

2.3      EQUIPMENT

A.   Performance and Configuration Requirements:

1.   Pumps Tag Numbers: 15LPMP610, 15LPMP620 and 15LPMP630.

2.   Pump service category:

a.   Pumped Fluid:  Centrate, slop, drainage and wastewater with solid up to 3 inches in diameter.

b.   Design Condition:  1,700 gpm at 48 FT TDH with minimum pump efficiency of 70 percent.

c.   Secondary  Condition:    1,417  gpm  at  26  FT  TDH  with  minimum  pump efficiency of 70 percent.

d.   Pumping Configuration: One or two pumps in parallel to any of three different discharge destinations. Pumps operating curves, single or parallel from lowest to full speed operation shall span the system curves for all three discharge destinations.

e.   Shutoff Condition: 0 gpm at 70 FT TDH.

f.    Installation Configuration: Full pedestal vertical installation per Drawings.

g.   Maximum Pump Speed: 1,200 rpm.

h.   Nameplate Driver Horsepower: Maximum 50.

i.    Drive Type: Variable speed drive (VFD).

j.    Drive Configuration: Flexible coupled.

k.   Minimum Solids Passage: 3-inch diameter.

l.    Suction  size  10-inch  diameter  minimum,  discharge  size  8-inch  diameter minimum.

B.   Assure increasing head characteristic from secondary design condition to shutoff condition.

C.  Provide pumps with net positive suction head requirements that are less than the available net positive suction head available at design condition specified.

2.4      ACCESSORIES

A.   See Section 11005, Equipment: Basic Requirements.

2.5      FABRICATION

A.   General:
1.   Pump casing strength to withstand 150 percent of shutoff head.

2.   Single suction non-clog type pump fabrication.

3.   Built-together units not acceptable.

4.   Fabricate casing for impeller removal without disturbing suction and discharge piping.

5.   Tap and plug openings for minimum 1/2 inch IPS suction and discharge gauge connections.
a.   Tap in discharge nozzle shall serve as a vent when gauge is not used.

6.   Provide volute and suction clean out hand hole.

B.   Suction and Discharge:
1.   ANSI Class 150-pound rated flanged nozzles for suction and discharge.

C.  Volute/Casing
1.   The volute shall be matched to the impeller and made of close-grained cast iron conforming to ASTM A48 CL30.  The volute is to be of one-piece circular constant flow, equalizing pressure design with smooth fluid passages large enough to pass any size solid that can pass through the impeller.

2.   The volute shall be flanged tangential discharge and capable of rotation in 45 degree increments to  accommodate piping orientation.   Diffusion vanes are  not permitted.

3.   The volute shall be furnished with large cleanout openings located at the impeller centerline, to allow access to the impeller.  Volute priming, drain and ½” minimum gauge connections shall be provided. Flanges shall be 125 pounds flat faced flanges per ANSI drilling.

4.   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.

D.  Impeller: The impeller shall be of the balanced non-clogging type made of close- grained cast iron conforming to ASTM A48 CL30.  It shall be of one-piece construction, single suction, enclosed three-vane, radial flow design with well-rounded leading vanes and then tapered toward the trailing edge for a circular flow pattern.   The waterways through the impeller will have extremely smooth contours, devoid of sharp corners, so as to prevent rags or stringy, fibrous material from catching or clogging.

1.   Secure to keyed shaft by stainless steel connector. The arrangement shall be such that the impeller cannot be loosened from torque in either forward or reverse rotation.

2.   Install replaceable type wear rings.

3.   Impeller adjustment (manufacturer's option):

a.   Alternate A:
1)   Replaceable case and impeller wear rings allowing a minimum of 1/4 inch wearing surface.
2)   Impeller wear ring with a Brinell hardness of 190-220.
3)   Fronthead/casing wear ring with Brinell hardness of 300-350.

b.   Alternate B:
1)   Externally adjustable shims or jackscrews with locking device to take up impeller wear using split ring shims and to be installed at outboard bearing for horizontal units.

E.   Shaft Seal:

1.   Mechanical Seal: Chesterton 442 split seal with flushing.

2.   Provide sealing/flushing liquid connection to seal box in convenient locations.

F.   Shafting and Sleeves:

1.   Size shaft to transmit full driver output.

2.   Accurately machine and construct shaft.

3.   Incorporate shaft sleeve (minimum Brinell hardness of 180) in stuffing box area to protect shaft from pumped liquid.

4.   Provide positive shaft seal between shaft sleeve and shaft for full length of sleeve.

5.   Fabricate shaft for maximum deflection of 0.002 inch measured at the stuffing box.

G.  Bearings, Bearing Support, and Frame:

1.   Provide bearing housings complete with grease seals and provisions to preclude moisture and foreign matter from entering both ends of the frame.

2.   Tap 3/4 inch drain hole in frame to convey leakage from packing gland.

3.   Supply bearings for a minimum ABMA L-10 life of 100,000 hours at design condition.

4.   Furnish radial inboard bearings of either ball or roller type suitable to sustain all loads encountered in service conditions.

5.   Provide axial thrust outboard bearings of deep groove single or triple row ball type or angular contact double row ball type suitable for thrust loads in two (2) planes.

H.  Rotation:

1.   Pump rotation to conform to piping arrangement shown on Drawings.

I.    Baseplate and Guarding:
1.   Pump  and  driver  base  shall  be  hot  dip  galvanized  ASTM  A36  heavy-duty fabricated steel with large access openings to facilitate grouting and deep channel drip lip design. Drainage connections shall be furnished at both ends.

2.   Each pump shall be provided with OSHA approved coupling guard. The coupling guard shall be factory mounted to pedestal to protect personnel from rotating parts at the coupling.

J.   Vertical Pump Support:  Pump shall be supported by cast iron or hot dip galvanized ASTM A36 fabricated steel pedestal base with openings large enough to permit access to the suction elbow and clean-out hand hole. Base shall be designed to support the assembled weight of the pump, coupling housing, bearing frame and motor. It shall safely withstand all stresses imposed thereon by vibration, shock and all possible direct, seismic and eccentric loads. Supports shall be of the pedestal type including the suction elbow. Base shall have adequate horizontal dimensions, foundation contact area, anchorage facilities and shall be of sufficient height so that the suction elbow will not touch the floor or foundation upon which the pump is mounted.

K.   Coating:

1.   Pumps and supports shall receive coat of an environmentally safe machinery enamel coating with high solids content. Refer to Section 09800, Protective Coating, for requirements.

L.   Fits and Hardware

1.   The volute/casing, fronthead, backhead, 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.

2.   All bolts, washers, nuts and hardware shall be 316 stainless steel.

M.  Motors:
1.   Motors shall be in accordance with Specification section 16220, Electric Motors.

2.6      SOURCE QUALITY CONTROL

A.   All Pumps:
1.   A certified factory hydrostatic and 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 vs flow, input horsepower, and efficiency relative to capacity from shutoff to 150 percent 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.

2.   Results of the performance tests shall be certified by a Registered Professional
Engineer in the State of California and submitted for approval before final shipment.

B.   Vibration Limitations (Field):
1.   The limits of vibration as set forth in the standards of the Hydraulic Institute shall govern.

If vibration tested values exceed the maximum specified, the manufacturer will have the option to either replace the pumps or to extend the manufacturer’s warranty for two more years.  Natural frequency or resonance shall not affect the operation of the pump at any point within the range specified.

2.7      MAINTENANCE MATERIALS

A.   Special Tools:  Furnish, together with the pumping units, one (1) set of any special tools, other than common plant mechanic’s tools, necessary to install, adjust, maintain or repair the pumping units or any of the components.

B.   Spare Parts:

1.   Furnish OCSD the following extra spare parts for each pump:

a.   Shaft Sleeve: One (1) each.

b.   Bearing Sets: One (1) set.

c.   Full Gasket Kits: One (1) set.

d.   Packing/Seals: One (1) set.

e.   Casing W ear Plates: One (1) set.

2.   Spare parts as listed above shall be furnished with the pumping units. These shall be packaged for long term storage in suitable heavy cardboard or wooden boxes, clearly marked with the contents.

PART 3 - EXECUTION

3.1      INSTALLATION

A.   See Section 11005, Equipment: Basic Requirements.

3.2      FIELD QUALITY CONTROL

A.   See Section 11005, Equipment: Basic Requirements.

3.3      MAINTENANCE OF INSTALLED EQUIPMENT

A.   Maintain the operability and functionality of all installed equipment between the time of  installation  and  the  commissioning  period.    See  Specification section  01660  for requirements.

3.4      MANUFACTURER’S SERVICES

A.   Furnish the services of authorized technical representatives of the Manufacturer to assist/inspect the installed equipment and to certify that the equipment has been properly installed and is ready to operate, train OCSD personnel, conduct pre-operational mechanical checkout of the equipment, place equipment into operation, optimize the performances of the equipment and perform the field performance testing.

B.   At a minimum, conduct three separate site visits as follows:

1.   Inspection of equipment installation (8 hours minimum)

2.   Training of OCSD personnel. See Specification section 01820 for requirements.

3.   Commissioning. See Specification section 01810 for requirements. Number of hours shall be as required to meet all testing and commissioning requirements, but shall not be less than 16 hours.

C.  Performance Test:  The pump shall be tested to develop the performance curves, for assurance of proper and vibration free operation.

1.     Data gathering shall be in accordance with Hydraulic Institute Standards.
Curves shall be plotted using the data obtained at the tests. All curves shall extend from shut-off to actual runout points. Curves shall include: head vs. capacity, brake horse power, mechanical efficiency and wire to water efficiency. There should be a minimum of 10 test points spaced at approximately equal head. Test data and pump curves shall be certified and three (3) copies of each shall be submitted along with electronic copy.

2.  Vibration shall be continuously monitored during all pump tests, After completing the performance test on the pump, the pump will be operated at variable speed from full speed to 50 percent of it and back to full speed and from shut-off to run out heads while monitoring the vibration.