REQUEST FOR BIDS (RFB)
FOR
CONSTRUCT ON-AIRPORT PORTION OF
DEICING FLUID FORCE MAIN (PHASE I)
(FEDERALLY FUNDED)
CONTROL NO. S06-118
ADDENDUM NO. 4
ISSUE DATE: 10/12/06
BID DEADLINE: 10/20/06 AT 2:00 PM Local
Time
This addendum is being issued to modify and clarify some sections of the RFB, as well as to answer
questions submitted by the extended Pre-Bid Question Deadline of September 28, 2006.
I. MODIFICATIONS:
1. REPLACE Attachment J, Construction Documents, Technical Specifications, SECTION 11301
Deicing Fluid Pumps, Pages 11301-1 through 11301-6, in its entirety with the new REVISED
SECTION 11301 Deicing Fluid Pumps, Revised Pages 11301-1 through 11301-6 (attached as
pages 8 through 14 of this addendum).
2. ADD to Attachment J, Construction Documents, Technical Specifications SECTION 15060 Pipes
and Fittings, Part 1 General, SCOPE 1.01, Page 15060-1, as item D:
D. All piping associated with the De-icing Pumping Station shall be mechanically
restrained with a pipe manufacturer approved device and/or adequately designed
concrete thrust blocks. Test pressure for all suction and discharge piping shall be 150
psig per AWWA specification.
3. ADD new sketches of the structure between ponds 3W and 3E, shown as pages 15 and 16 of this
addendum.
END OF THE MODIFICATIONS SECTION
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 1 of 16
II.
ANSWERS TO QUESTIONS:
Pumps and Other Specification Questions
1.
The project specifications and drawings are contradictory regarding a few items in Division 5.
Please clarify the following:
a.
Are the stairs tread and grating painted (per specs) or galvanized (per dwgs)?
b.
Is the roof deck 1-1/2” (per specs) or 3” (per dwgs)?
c.
Is the grating at the stair landing 2” (per specs) or 1-1/2” (per dwgs)?
d.
Is a plastic cover required on the handrails (per specs) or not (per dwgs)?
Answer:
a.
b.
c.
d.
2.
Stair treads and grating shall be galvanized as are specified on sheet A1.
The roof deck shall be 3” as is specified on sheet A1.
The grating at the stair landing is 1-1/2” as is specified on sheet A1 and S3.
Handrails are galvanized and plastic covers are not required.
Please clarify the size of the ground rods and ground wire at the transformer pad.
Answer: Ground rod is ¾” diameter copper and ground wire size is 4/0, at the transformer pad.
3.
What is the procedure should we encounter asbestos when splicing into the existing cable at the
duct bank?
Answer: The cable that will be spliced was installed approximately 3 years ago. Therefore, asbestos
should not be encountered when working with this cable. Nevertheless, if asbestos must
be removed as part of the required scope of work, the contractor should follow the
requirements in the terms and conditions regarding unforeseen conditions.
4.
The specifications state that the pumps come with control panels including starters and level
controls. Drawings E-3 calls for a MCC with starters. Only one or the other would be required,
which is correct?
Answer: The MCC should be provided with starters, as called for on sheet E3.
5.
The drawings do not show any control wiring at the MCC or the owner provided sampler; is the
control wiring required?
Answer: No control wiring is required.
6.
Specification section 15010.3.11 states that the electrical contractor will be providing empty
conduit for controls, is this correct
Answer: No empty conduits for controls will be required.
7.
A dedicated circuit for the transformer is not called for, therefore, specification section 16271
(protective relaying) is not applicable. Is this correct?
Answer: Specification section 16271 is not applicable.
8.
The size, type and circuit amperage rating of the cable that is to be spliced into is not provided.
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 2 of 16
This information is necessary in order to provide the correct size and type of cable in the duct
bank as no circuit specification is given. Please advise.
Answer: The existing primary cable in the manhole CT#9AT is 500 MCM cable. The new feed
for the pump station, from existing manhole MH A-3 to the new transformer, is also a
500 MCM cable. The contractor shall provide proper grounding and protection on either
side of the transformer. The new cable shall be certified by the manufacturer that is
suitable, and test for a 500 KVA load.
9.
Except for the underground, there is no conduit specification. Are we to assume anything that
meets code is acceptable?
Answer: Conduits to be provide per applicable code.
10. A note on drawing number A2 call for foamed-n-place insulation to be installed within the block
cores (unless concrete is required), however, no specification section is provided indicating the
insulation requirements. Please advise.
Answer: Foamed-in-place insulation shall be RAPCO FOAM™ or approved equal. Contractor may
contact John Ingrao from DANA-Energy Savers, Inc. (Phone.586-463-3625, Fax 586-4639460) for more information.
11. Drawing E2 calls for two light wall packs on the exterior of the building. However, a fixture
schedule is not provided. What type of fixture is required?
Answer: The wall pack shall be a 70 watt light. Catalog number for the wall pack light fixture is
LITHONIA, TWP175MTBLP1, programmable timer shall be GRAINGER, catalog item #
4WZ36, or McMASTER catalog, item # 70915K71, or equivalent. The contractor shall
supply necessary associated wiring and relays.
12. Since the proposed MCC includes the starters for the pumps, please confirm that the Control
Panel specified in Specification Section 11301.2.02.F is not required.
Answer: Control Panel in Section 11301.2.03.F is not required.
13. Are the low level and high level float switches required to be furnished and installed? If so,
please describe and/or show the installation and the wiring requirements.
Answer: Low level and high level float switches are required to be furnished and installed per
specification section 11301-2.03E
14. Are there any wiring requirements associated with the magnetic flowmeters? If there are, please
describe and/or show.
Answer: There is no wiring associated with the magnetic flow meters.
15. Please confirm that there is no wiring associated with the control valves.
Answer: There is no wiring associated with the control valves.
16. Please confirm that the control of the pumps is a manual selection of the desired pump with the
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 3 of 16
on-off operation controlled by a programmable timer.
Answer: The pumps will be controlled manually with a programmable timer.
17. Section 11301, 1.05 - Are the shut-off heads listed based on the "system" curve or a
manufacturer's "pump" curve? If they are of the "system" curve please explain the need for
these specific shutoff heads and are they minimums or maximums?
Answer: Pump shutoff head values are based on manufacturer data, and are maximums.
18. Section 11301, 1.07, C - We found no system curve in the specifications nor in addendums 1
and 2. Please provide.
Answer: System curves are provided in the REVISED SECTION 11301, DEICING FLUID
PUMPS, specification section included in this addendum.
19. Section 11301, 2.03, A and Paragraph H - The specifications calls out "guide rails" and then
goes on to say that "guide cables" are not acceptable. The immediate question is why "no" to
guide cables?
Answer: The Contractors are to bid the project based on the drawings and specifications. However,
the Contractors may provide a proposed exception to the drawings and specification in
accordance with Section 5 of the Instruction Section of the RFB.
20. Section 11301, Paragraph H, Pump Design - No material is listed for the guide rails. Please
advise if it is 304, 316 or some other grade of stainless steel.
Answer: Guide Rails shall be 304 Stainless Steel.
21. Section 11301, Paragraph H - Pump Design - We seal the connection between the pump and
discharge elbow with a replaceable profile gasket. Please advise why this is unacceptable.
Answer: Metal-to-Metal contact is preferred to a gasket, as there will be considerable difficulty in
replacing the gasket.
22. Section 11301, Paragraph H, Requirements - Voltage is listed as 450 in line two. We suspect
this is a "typo". Please confirm voltage.
Answer: Voltage should be 480V / 3 ph / 60 hertz (see revised Deicing Fluid Pump Specification,
Section 11301 included in this addendum.
23. Section 11301 Paragraph H, Requirements -There is no material specified for the power cable
jacket or cover. Our experience with other airport applications would indicate that there may be
the potential for jet fuel to get in with the deicing mix. If this is the case a tefzel power cable
jacket or equivalent that is resistant to jet fuel should be specified. Please advise if jet fuel will be
present and revise the specification accordingly.
Answer: See revised Deicing Fluid Pump Specification, Section 11301, pages 9 through 16.
24. Section 11301 Paragraph H, Pump Construction - We would recommend Viton o-rings for the
pumps if jet fuel may be present. Revise spec accordingly.
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 4 of 16
Answer: See revised Deicing Fluid Pump Specification, Section 11301, pages 8 through 14.
25. Paragraph H, Cooling System- While KSB does offer closed loop cooling systems for dry pit
applications, we do not understand why there is a closed loop cooling system required. I have
read the spec and the notes on the drawings regarding the operation of the pumps and do not
understand this requirement. The pumps are submerged in a wet well and there are timers to
bring them on line when sewer capacity permits. To protect the pumps from running when the
minimum submergence is not met you have a float switch that will prevent the pumps from
coming on even when the timer calls for it. In addition, the pumps have thermal protection to
shut them down if operated dry. Please explain this requirement.
Answer: The Contractors are to bid the project based on the drawings and specifications. However,
the Contractors may provide a proposed exception to the drawings and specification in
accordance with Section 5 of the Instruction Section of the RFB.
26. Section 11301 Paragraph H, Mechanical Seals - Our seal faces use Silicon Carbide in lieu of
Tungsten. It is superior to Tungsten. Please add Silicon Carbide to spec.
Answer: See revised Deicing Fluid Pump Specification, Section 11301, pages 8 through 14.
27. Section 11301 Paragraph H, Mechanical Seals- While offered on larger motors, 60 hp and
larger, the leakage chamber is not available on the pumps for this job. We use the moisture
sensor at the lowest point of the stator housing to warn of seal failure. This system has been in
use successfully for over 20 years. Delete this requirement or add our method as acceptable.
Answer: This particular application requires the leakage chamber with fluid level monitoring. The
specification will remain as written.
28. Section 11301 Paragraph H, Impeller- Our impellers are non-clog design as used for sewage,
but this is a deicing forcemain so why is an impeller for 5% sludge called out?
Answer: The water from the retaining pond may contain large amounts of silt/mud. This is the
reason for the sludge handling requirement.
29. Section 11301 Paragraph H, Volute/Suction Cover - "Spiral shaped, sharp-edged grooves" are a
proprietary design by Flygt and we do not see the need for handling deicing solution. Please
explain this requirement.
Answer: No proprietary design was intended, KSB may use their standard design providing that the
design substantially complies with the specifications.
30. Section 11301 Paragraph H, Protection - KSB uses a "PumpSafe" module in lieu of the Mini
CAS. Please add to spec.
Answer: See revised Deicing Fluid Pump Specification, Section 11301, pages 8 through 14.
31. Section 11301 2.03 Accessories - Since KSB is a competitor of Flygts we will offer equivalent
floats by another manufacturer. Is this acceptable?
Answer: Equivalent float switches are acceptable as long as the contract terms and conditions are
complied with. See revised Deicing Fluid Pump Specification, Section 11301, pages 8
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 5 of 16
through 14.
Miscellaneous Other Questions
32. The site plan shows the location of the Pump Station to be about 1,500 feet west of Middlebelt
Road. Is it possible to set up an entrance at Middlebelt Road? If yes, please outline the
requirements and cost.
Answer: A Middlebelt Road entrance will require the contractor to provide a guard booth complete
with electricity, lighting, and spare outlets; telephone service; air conditioning and heat.
Guard rails will need to be installed on the entrance and outbound sides of the booth. The
booth would need to be set off Middlebelt Road approximately 100 feet, and a 10-foot tall
security fence with 3 strands of barb wire needs to be installed on both sides of the
entrance lane, between the road and the booth. A guard would need to be hired full time
from the WCAA Security Division.
33. A note on Drawing SP-5 states R/W 3R/21L will be closed for paving. Approximately when will
this activity occur and for how long?
Answer: Runway 3R/21L will be shut down from approximately April 1, 2007 through November 15,
2007.
34. Please provide the following information:
a. Maximum water surface recorded in Pond 3W.
b. Approximate average area of Pond 3W.
c. Lowest elevation that can be reached in Pond 3W by draining by gravity to Pond 3E.
d. Approximate land area that drains into Pond 3E.
e. Drawing of structure between Pond 3W and Pond 3E.
f. Is rain fall the only source of flow into Pond 3W during the summer?
g. It was stated by one member of the party conducting the site visit that they would or
could pump down Pond 3W. Please clarify if this would be a continuous operation while
working in Pond 3W.
h. What size and weight of encasing pipe is required for the 18” DIP?
i. Are gravity flow pipes required to be pressure tested, if so please specify?
j. What type of backfill material is acceptable around the 48” inlet manhole in Pond 3W.
k. Drawing C-1 shows approximately 52 feet of 18” pipe under the berm has to be jacked and
bored. Are these limits a vertical plane through the berm or can the berm be open cut to
these limits with the cut sloping back into the berm?
Answer:
a.
b.
c.
d.
e.
f.
g.
The maximum water surface elevation is 636.5 mean sea level (msl).
Approximate average area is 22 acres.
Lowest elevation of pond 3W by gravity drainage is 628.5 msl.
Approximate land area draining to pond 3W is 590 acres
Refer to the two sketches attached on pages 15 and 16 of this addendum.
Rainfall is the only source of flow into pond 3W during the summer
The pond can be lowered to elevation 628 msl without pumping. If the pond must be lower
than 628 msl, the contractor must provide the necessary equipment, labor, and materials to
lower the elevation.
h. Casing pipe shall be Steel, 30” minimum diameter, and 0.375” minimum wall thickness.
i. Gravity flow piping shall be tested at 25 psig for 2 hours
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 6 of 16
j. Porous backfill shall be MDOT 6A.
k. See note made on sheet. FM-301:“Open cutting of berm will not be allowed. Portion of
piping under berm to be installed by Jack N Bore or directional drill.” The berm shall not be
open cut within the vertical limits of the casing pipe between station 100+76 and 101+28.
END OF ANSWERS TO QUESTIONS SECTION
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 7 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
REVISED SECTION 11301
DEICING FLUID PUMPS
PART 1 GENERAL
1.01
SECTION INCLUDES
A. Four de-icing fluid submersible pumps suitable for waste de-icing fluid.
1.02
RELATED SECTIONS
A. Section 03300, 15060, 15100, 16060
1.03
REFERENCES
A. NEMA MG 1 – Motors and Generators; National Electrical Manufacturers Association;
B. NFPA 70 – National Electrical Code; National Fire Protection Association;
C. ASTM – 2004 American Society of Testing Materials
1.04
SYSTEM DESCRIPTION
A. Complete Factory built submersible pump for placement in a concrete sump chamber with control
panel and all accessories.
1.05
DESIGN REQUIREMENTS (explosion Proof Submersible Pumps)
Pump No.
Discharge
Operating
Head (ft)
Suggested
HP
Shut-off Head
(ft)
P-1
NIC
P-2
1275 gpm
180
260
100
P-3
850 gpm
100
180
50
P-4
630 gpm
80
120
25
P-5
400 gpm
60
90
10
See enclosed system head curve.
1.06
SUBMITTALS
A. Product Data: Provide catalog information.
B. Shop Drawings: Indicate Dimensions, Electrical requirements, pump curves.
C. Manufacturer’s instructions: Indicate Start up instructions.
D. Maintenance Data: Provide Maintenance Manual.
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-1
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 8 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
1.07
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
QUALITY ASSURANCE
A. Manufacturer Qualifications: Company specializing in manufacturing products specified in
this section, with not less than three years of documented experience.
B. Installer Qualifications: Company specializing in performing the work of this section with
minimum 3 years of experience.
C. Design: See attached system curve for use by pump manufacturer.
D. Products Requiring Electrical Connection: Listed and classified by UL as suitable for the
purpose specified and indicated.
PART 2 PRODUCTS
2.01
MANUFACTURERS
A. Flygt
B. KSB
C. Davis-EMU
D. Or equivalent product meeting the specifications
2.02
COMPONENTS
Four Submersible Pumps/Motors: Internal guide rail assembly, base elbow anchor bolts, lift
chains, 3 level controls, motor cables, roof hatches and wall mounted control panel.
2.03
Pump No.
Size
Model
Product
P-1
Not in Contract
(NIC)
Future
P-2
6” Flygt
CP-3300-6
NP
3301.091HT
P-3
4” Flygt
NP 3202-468
NP 3202.180
P-4
4” Flygt
80
NP 3171.090
P-5
4” Diameter
60
CP-3127-090
ACCESSORIES – EFFLUENT PUMPS
A. Guide Rail Assemblies: Designed for exterior removal of pumps and motor stainless steel pipe,
(type 304) rails, non sparking bronze construction guide, brackets and hold downs, dual O ring
seals around pump nozzle, discharge case bolted to wetwell floor.
B. Discharge Piping: Ductile Iron Pipe, connected to discharge casing assembly and terminating at
discharge flange.
C. Shut Off Valves: Cast Iron
D. Check Valves:
Swing check with counter weight, bronze seat, ss shaft, spring loaded
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-2
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 9 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
E. Junction Box: Aluminum with O ring seal cover and seal type cord grips for incoming wires,
provide for pour in type sealant. Assembly to meet UL listing as noted.
F. Level Controls: Float switches in a corrosion resistant polypropylene housing with 18 gauge, 2
wire, SJOWA/A jacketed cable and intrinsically safe relays. No cable splices allowed; terminate in
junction box. Provide SS bracket mounting for level control adjustment without use of tools.
G. Control Panel: NEMA 12, fiberglass, ss piano hinge, 2 SS letches and padlock hasp. Back panel
shall be attached to mounting standoffs in enclosure with screws; UL listed assembly.
1. Provide pump breakers, alarm and control circuit fuses, IEC rated starters with 1 pole
compensated overload relays, pump H O A switches, pump run lights, CT with fusing,
alarm test switch, alternator relay, override relay, two ground lugs, red exterior alarm
light and anti condensation heater (100 watt)
Additional alarm terminals shall include: pump failure, high motor
temperature, seal failure. Provide extra terminal for interior alarm light
function.
Provide two elapsed hour meters, one for each pump.
2. All wiring shall be neat, color-coded, terminate in box clamp terminal block. Provide wiring
diagram mounted inside panel.
Mount panel and power hookups all inside a wall mounted, NEMA 12
locking enclosure.
2.04
REQUIREMENTS
Furnish and install 4 submersible non-clog wastewater pumps. Each pump shall be equipped with an HP
submersible electric motor, connected for operation of 480 volts, 3 phase, 60 hertz, wire service, with 50
feet of submersible cable (SUBCAB) suitable for submersible pump applications. The power cable shall
be sized according to NEC and ICEA standards and also meet with P-MSHA Approval. The power cable
jacket shall be Tefzel or equivalent, resistant to jet fuel. The pump shall be supplied with a mating cast
iron discharge connection and be the various GPM at the TDH as shown on the drawings. Shut off head
shall be as shown on the drawings feet (minimum). Minimum pump efficiency shall be 60%. Each pump
shall be fitted with 35 feet of stainless steel lifting chain. The working load of the lifting system shall be
50% greater than the pump unit weight.
A. PUMP DESIGN
The pump(s) shall be automatically and firmly connected to the discharge connection. Guide rail
system shall consist of two (2) schedule 40, stainless steel guide bars per pump with stainless
steel intermediate guide rails support brackets as recommended by the manufacturers. Guide
cables will NOT be acceptable. There shall be no need for personnel to enter the wet-well.
Sealing of the pumping unit to the discharge connection shall be accomplished by a machined
metal to metal watertight contact. Sealing of the discharge interface with a diaphragm, O-ring or
profile gasket will not be acceptable. No portion of the pump shall bear directly on the sump floor.
B. PUMP CONSTRUCTION
Major pump components shall be of grey cast iron, ASTM A-48, Class 35B, with smooth surfaces
devoid of blow holes or other irregularities. All exposed nuts or bolts shall be of stainless steel
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-4
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 10 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
construction. All metal surfaces coming into contact with the pumpage, other than stainless steel
or brass, shall be protected by a factory applied spray coating of acrylic dispersion zinc
phosphate primer with a polyester resin paint finish on the exterior of the pump.
Sealing design shall incorporate metal-to-metal contact between machined surfaces. Critical
mating surfaces where watertight sealing is required shall be machined and fitted with Nitrile
suitable for resisting jet fuel, or Viton rubber O-rings. Fittings will be the result of controlled
compression of rubber O-rings in two planes and O-ring contact of four sides without the
requirements of a specific torque limit.
Rectangular cross sectioned gaskets requiring specific torque limits to achieve compression shall
not be considered as adequate or equal. No secondary sealing compounds, elliptical O-rings,
grease or other devices shall be used.
C. COOLING SYSTEM
Each unit shall be provided with an integral motor cooling system. A motor cooling jacket shall
encircle the stator housing, providing for dissipation of motor heat regardless of the type of pump
installation. An impeller, integral to the cooling system and driven by the pump shaft, shall provide
the necessary circulation of the cooling liquid through the jacket. The cooling liquid shall pass
about the stator housing in the closed loop system in turbulent flow providing for superior heat
transfer. The cooling system shall have one fill port and one drain port integral to the cooling
jacket. The cooling system shall provide for continuous pump operation in liquid or ambient
temperatures of up to 104ºF. (40ºC.). Operational restrictions at temperatures below 104ºF are
not acceptable. Fans, blowers or auxiliary cooling systems that are mounted external to the
pump motor are not acceptable.
D. CABLE ENTRY SEAL
The cable entry seal design shall preclude specific torque requirements to insure a watertight and
submersible seal. The cable entry shall consist of dual cylindrical elastomer grommets, flanked by
washers, all having a close tolerance fit against the cable outside diameter and the entry inside
diameter. The grommets shall be compressed by the cable entry unit, thus providing a strain
relief function. The assembly shall provide ease of changing the cable when necessary using the
same entry seal. The cable entry junction chamber and motor shall be sealed from each other,
which shall isolate the stator housing from foreign material gaining access through the pump top.
Epoxies, silicones, or other secondary sealing systems shall not be considered equal.
E. MOTOR
The pump motor shall be a NEMA B design, induction type with a squirrel cage rotor, shell type
design, housed in an air filled, watertight chamber. The stator windings shall be insulated with
moisture resistant Class H insulation rated for 180ºC (356ºF). The stator shall be insulated by the
trickle impregnation method using Class H monomer-free polyester resin resulting in a winding fill
factor of at least 95%. The motor shall be inverter duty rated in accordance with NEMA MG1, Part
31. The stator shall be heat-shrink fitted into the cast iron stator housing. The use of multiple step
dip and bake-type stator insulation process is not acceptable. The use of pins, bolts, screws or
other fastening devices used to locate or hold the stator and that penetrate the stator housing are
not acceptable. The motor shall be designed for continuous duty while handling pumped media of
up to 140ºF. The motor shall be capable of withstanding at least 15 evenly spaced starts per
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-4
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 11 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
hour. The rotor bars and short circuit rings shall be made of aluminum. Three thermal switches
shall be embedded in the stator end coils, one per phase winding, to monitor the stator
temperature. These thermal switches shall be used in conjunction with and supplemental to
external motor overload protection and shall be connected to the motor control panel. The
junction chamber shall be sealed off from the stator housing and shall contain a terminal board
for connection of power and pilot sensor cables using threaded compression type terminals. The
use of wire nuts or crimp-type connectors is not acceptable. The motor and the pump shall be
produces by the same manufacturer.
The motor service factor (combined effect of voltage, frequency and specific gravity shall be 1.15.
The motor shall have a voltage tolerance of +/- 10%. The motor shall be designed for continuous
operation in up to a 40ºC. ambient and shall have a NEMA Class B maximum operating
temperature rise of 80ºC. A motor performance chart shall be provided upon request exhibiting
curves for motor torque, current, power factor, input/output kW and efficiency. The chart shall
also include data on motor starting and no-load characteristics.
Motor horsepower shall be sufficient so that the pump is non-overloading throughout its entire
performance curve, from shut-off to run-out. The motor and cable shall be capable of continuous
submergence underwater without loss of watertight integrity to a depth of 65 feet or greater.
F. BEARINGS
The integral pump/motor shaft shall rotate on two bearings. The motor bearings shall be sealed
and permanently grease lubricated with high temperature grease. The upper motor bearing shall
be a two row angular contact ball bearing. The lower bearing shall be a two row angular contact
ball bearing to handle the thrust and radial forces. The minimum L10 bearing life shall be 50,000
hours at any usable portion of the pump curve.
G. MECHANICAL SEALS
Each pump shall be provided with a positively driven dual, tandem mechanical shaft seal system
consisting of two seal sets, each having an independent spring. The lower primary seal, located
between the pump and seal chamber, shall contain one stationary and one positively driven
rotating corrosion resistant silicone or tungsten-carbide ring. The upper secondary seal, located
between the seal chamber and the seal inspection chamber, shall contain one stationary and one
positively driven rotating corrosion resistant tungsten-carbide seal ring. All seal rings shall be
individual solid sintered rings. Each seal interface shall be held in place by its own spring system.
The seals shall not depend upon direction of rotation for sealing. Mounting of the lower seal on
the impeller hub is not acceptable. Shaft seals without positively driven rotating members or
conventional double mechanical seals containing either a common single or double spring acting
between the upper and lower seal faces are not acceptable. The seal springs shall be isolated
from the pumped media to prevent materials from packing around them, limiting their
performance.
Each pump shall be provided with a lubricant chamber for the shaft sealing system. The lubricant
chamber shall be designed to prevent overfilling and shall provide capacity for lubricant
expansion. The seal lubricant chamber shall have one drain and one inspection plug that are
accessible from the exterior of the motor unit. The seal system shall not rely upon the pumped
media for lubrication.
The area about the exterior of the lower mechanical seal in the cast iron housing shall have cast
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-6
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 12 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
in an integral concentric spiral groove. This groove shall protect the seals by causing abrasive
particulate entering the seal cavity to be forced out away from the seal due to centrifugal action.
A separate seal leakage chamber shall be provided so that any leakage that may occur past the
upper, secondary mechanical seal will be captured prior to entry into the motor stator housing.
Such seal leakage shall not contaminate the motor lower bearing. The leakage chamber shall be
equipped with a float type switch that will signal if the chamber should reach 50% capacity.
H. PUMP SHAFT
The pump and motor shaft shall be a single piece unit. The pump shaft is an extension of the
motor shaft. Shafts using mechanical couplings shall not be acceptable. The shaft shall be
stainless steel – ASTM A479 S43100-T. Shaft sleeves will not be acceptable.
I.
IMPELLER
The impeller shall be of gray cast iron, ASTM A-48 Class 35B, dynamically balanced, semi-open,
multi-vane, back swept, screw-shaped, non-clog design. The impeller leading edges shall be
mechanically self-cleaned automatically upon each rotation as they pass across a spiral groove
located on the volute suction. The screw-shaped leading edges of the impeller shall be hardened
to Rc 45 and shall be capable of handling solids, fibrous materials, heavy sludge and other matter
normally founding wastewater. The screw shape of the impeller inlet shall provide an inducing
effect for the handling of up to 5% sludge and rag-laden wastewater. The impeller to volute
clearance shall be readily adjustable by the means of a single trim screw. The impeller shall be
locked to the shaft, held by an impeller bolt and treated with a corrosion inhibitor.
J. VOLUTE/SUCTION COVER
The pump volute shall be a single piece gray cast iron, ASTM A-48, Class 35B, non-concentric
design with smooth passages of sufficient size to pass any solids that may enter the impeller.
Minimum inlet and discharge size shall be as specified. The volute shall have integral spiralshaped, sharp-edged groove(s) that is cast into the suction cover. The spiral groove(s) shall
provide the sharp edge(s) across which each impeller vane leading edge shall cross during
rotation so to remain unobstructed. The internal volute bottom shall provide effective sealing
between the multi-vane semi-open impeller and the volute. No proprietary design was intended.
Manufacturers can utilize their well-proven and durable designs.
K. PROTECTION
Each pump motor stator shall incorporate three thermal switches, one per stator phase winding
and be connected in series, to monitor the temperature of the motor. Should the thermal switches
open, the motor shall stop and activate an alarm. A float switch shall be installed in the seal
leakage chamber and will activate if leakage into the chamber reaches 50% chamber capacity,
signaling the need to schedule an inspection.
The thermal switches and float switch shall be connected to a Mini CAS or PumpSafe module
control and status-monitoring unit. The Mini CAS unit shall be designed to be mounted in the
pump control panel.
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-7
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 13 of 16
Wayne County Airport Authority
Detroit Metropolitan Airport S06-118
Revised Construction On-Airport Portion of Deicing Force Main
CIP #IF-706.B.00.0
PART 3 EXECUTION
3.01
EXAMINATION
A. Verify that site is ready for pump station installation.
3.02
PREPARATION
A. Install in accordance with manufacturer’s instructions.
3.03
FIELD QUALITY CONTROL
A. Inspect for proper wiring of power, bump motors to check rotation, settling of floats and alarm.
B. Test for regular pump operation by filling wet well with potable water and cycling all pumps,
including remote operation.
3.04
ADJUSTING
A. Adjust equipment for smooth operation.
3.04 CLEANING
A. Clean pump station, enclosure and adjacent site.
END OF SECTION
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
REVISED 11301-8
DETROIT FLUID PUMP
S06-118 Addendum #4 - Page 14 of 16
Pond 3W-3E Structure (Not to Scale)
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 15 of 16
Pond 3W-3E Structure (Not to Scale)
END OF ADDENDUM #2
THIS ADDENDUM MUST BE ACKNOWLEDGED ON THE BID FORM IN THE RFB
S06-118 Addendum #4 - Page 16 of 16