Of 3 ADDENDUM #1 CITY of NIXA, MISSOURI SLUDGE DEWATERING FACILITY IMPROVEMENTS This Addendum #1, Dated February 8, 2021

ADDENDUM #1 CITY OF NIXA, MISSOURI SLUDGE DEWATERING FACILITY IMPROVEMENTS

This addendum #1, dated February 8, 2021 hereby modifies the plans and specifications for the above referenced project as follows:

A. PLANS:

1. Plan Sheet 5 of 12: Contractor shall install hydrant with a ¾” hose bib on the 1-1/2 inch Sch 80 water supply line adjacent to the proposed shaftless conveyor to allow for periodic cleanup of conveyor.

2. Plan Sheet 6 of 12: Contractor shall provide Siemens Model Mag 5100W Flow Sensor w/Siemens Model Mag 5000 signal converter or approved equal.

3. Plan Sheet 8 of 12: Please note that the original plans indicate a conveyor incline of 16 degrees. The revised angle of inclination will be 22 degrees. Manufacturer will account for this increase in angle when determining the required length of conveyor.

4. Plan Sheet 8 of 12: All reference to automatic discharge valve at the sludge conveyor shall be eliminated. No valve will be required.

5. Plan Sheet 8 of 12: Reference to a portable hoist and Gantry crane shall be disregarded. No hoist or crane will be required.

B. SPECIFICATIONS:

1. Contractor shall remove the original Bid Form from the specifications and insert the attached revised Bid Form indicating the equipment requirement for submitting the Base Bid.

2. Contractor shall remove the original specification section 11A-Centrifuge and insert the attached specification.

3. Contractor shall remove the original specification section 11B-Dewatered Sludge Conveyor and insert the attached specification.

3. Contractor shall remove specification section 11F-Gantry Crane from the specification booklet. Gantry Crane will be purchased at a later date.

4. Division 2 Section 2A-Centrifuge should read Division 11 Section 11A-Centrifuge. Page 11A-1 Design Requirements paragraph B shall be revised as follows:

The sludge to be dewatered will be product of municipal water or wastewater treatment and shall be aerobically digested sludge.

Page 1 of 3 5. Contract Agreement: Article 3 Contract Time, Paragraph 3.1 shall be revised to read:

3.1 The work will be substantially completed on or before November 30, 2021, and completed and ready for final payment on or before December 31, 2021.

6. Division 2 Section 2A-Centrifuge should read Division 11 Section 11A-Centrifuge. Page 11A-1 Design Requirements paragraph B shall be revised as follows:

B. The sludge to be dewatered will be product of municipal water or wastewater treatment. Prior to dewatering sludge will be aerobically digested.

7. Division 11A Section 1.4 Quality Assurance Paragraph A on page 11A-2: It is the intent of the specifications that the following paragraph supersedes any other requirements of the specifications:

A. The manufacturer shall guarantee the decanter centrifuge to be free from defects in materials and workmanship for a period of twelve (12) months following installation or eighteen (18) months following the delivery. Any defects found within the warranty period shall be repaired or defective components replaced. Ancillary and control components shall be warranted per the original equipment manufacturer’s warranty.

8. Division 11A Section 2.13 Instrumentation and Controls Paragraph C on page 11A-9: Note that this paragraph specifies a Pilz safety emergency stop relay. It is intended that the safety emergency stop relay may be Siemens, Pilz or equal.

9. Division 11A Section 2.13 Instrumentation and Controls Paragraph E on page 11A-9: Note that this paragraph specifies a Siemens redundant control power supply. It is intended that the safety emergency stop relay may be Siemens or equal.

C. GENERAL:

1. The contractor shall provide a support structure for the proposed centrifuge in accordance with the centrifuge manufacturer’s recommendations.

2. The contractor shall provide supports for the discharge end of the shaftless conveyor in accordance with the conveyor manufacturer’s recommendations.

2. It is the intent of the bidding documents that the centrifuge manufacturer shall furnish a programmable logic controller (PLC) capable of controlling the centrifuge unit, sludge feed pump, inclined screw conveyor, polymer preparation system and the wash water valves. Centrifuge manufacturer shall furnish the centrifuge unit, support structure for centrifuge unit and polymer preparation system. Sludge feed pumps, electromagnetic flow meter and inclined screw conveyor will be supplied by others.

Page 2 of 3 Each Contractor submitting a bid shall acknowledge receipt of this Addendum #1 in the space provided below and shall file with and attach to his/her bid.

The undersigned hereby acknowledges receipt of Addendum #1 to the Contract Documents for the City of Nixa Sludge Dewatering Facility Improvements.

______DATE:______BIDDER’S SIGNATURE

SHAFFER & HINES, INC. P.O. Box 493, 729 W. Center Circle, Suite 101 Nixa, Missouri 65714 (417) 725-4663 Fax: (417) 725-5230

Page 3 of 3 SLUDGE DEWATERING FACILITY IMPROVEMENTS FOR THE CITY OF NIXA, MO BID FORM

Before completing and executing the following Bid Form, each Bidder shall examine the Bidding Requirements, Contract Forms, Supplementary Conditions, Specifications, Drawings, and other proposed Contract Documents, and all Addenda thereto; and shall be acquainted with and fully understanding (1) the extent and character of the work covered by this Bid Form; (2) the location, character and condition of existing roads, streets, highways, railroads, pavements, surfacing, walks, driveways, curbs, gutters, trees, sewers, utilities, drainage courses and structures, and other installations, both surface and underground, which may affect or be affected by the proposed work; (3) the location, arrangement, and specified requirements of the proposed work; (4) the nature and extent of excavations to be made, and the type, character, and general condition of materials to be excavated; (5) the necessary handling and rehandling of excavated materials, including construction of fills and embankments; (6) the location and extent of necessary or probable dewatering requirements; (7) the difficulties and hazards to the work which might be caused by storm or flood water; (8) local conditions relative to labor, transportation, hauling, and rail delivery facilities; and (9) all other factors and conditions affecting or which may be affected by the work.

Each bidder shall hereby propose to furnish all materials, equipment, supplies, and appurtenances, to provide all construction equipment and tools; to perform all necessary labor and supervision; and to construct, install, erect, equip, and complete all work stipulated in, required by, and in accordance with the proposed contract documents and the drawings, specification, and other documents referred to therein (as altered, amended or modified by addenda) at the unit or lump sum prices stated on the following next pages.

Equipment/materials proposed by the bidder and equipment/materials provided shall meet or exceed the requirements of the specifications, drawings and other contract documents in the opinion of the Owner and Engineer. The listing of manufacturers in the specifications and plans is intended to establish a standard and the words “or equal” if not stated are implied. The naming of a manufacturer in the specifications, plans, addendums, and other contract documents does not constitute a waiver of the specifications or other requirements by that manufacturer, but does recognize the general understanding that the named manufacturer can produce a product meeting the intent of the plans and specifications and may be utilized by the Contractor for bidding in addition to any other manufacturers approval.

The Owner reserves the right to reject any proposed equipment/material which does not meet any of the specified requirements and reserves the right to require provision of equipment meeting all the specifications without a change in the bid price.

Each Bidder shall include in his/her bid prices any paid up licenses, patent fees or other costs necessary for the use of the equipment and provided materials, if required by the manufacturer.

Each Bidder shall fully and accurately complete the following Bid Form and shall provide a unit price (where applicable) and a total price for each item shown. Prices provided shall include all labor, materials, overhead, profit, insurance, mobilization, license fees, and other costs,

BF-1 SLUDGE DEWATERING FACILITY IMPROVEMENTS FOR THE CITY OF NIXA, MO BID FORM considerations, and requirements as indicated in the plans, specifications, and other contract documents.

Attention of the Bidder is directed to the Instructions to Bidders and Measurement and Payment Sections of the Specifications and Contract Documents in addition to the other contract documents, specifications and construction plans.

Execution of this Bid Form by the Bidder affirms the Bidder’s acceptance and understanding thereof.

CONTRACT ITEMS:

DEWATERING FACILITY IMPROVEMENTS

Item No. Lump Sum Item Descriptions and Bid

1.0 Sludge Centrifuge Installation at the Wastewater Treatment Plant

Lump sum price to provide sludge feed progressive cavity pump and piping at existing lift station, all required removal and disposal of existing concrete, and grated walkways indicated on the construction drawings and replacement with a reinforced concrete floor slab, providing sludge centrifuge, conveyor, polymer system, elevated walkway, heating and ventilation and all other appurtenances necessary for completion of the requested construction activities. All materials, labor, shipping, equipment and services for a complete installation in accordance with the specifications, manufacturer’s design and shop drawings.

Only acceptable manufacturers equipment shall be used in preparing the Contractor’s Base Bid. The Contractor shall submit his Base Bid based on the following acceptable equipment manufacturers.

LIST OF ACCEPTABLE BASE BID EQUIPMENT MANUFACTURERS

Equipment Item Manufacturer

Centrifuge and Dewatering Controls FLOTTWEG

Centrifuge Feed PC Pump SEEPEX

Polymer Feed System FLUID DYNAMICS

Conveyor System KWS

BF-2 SLUDGE DEWATERING FACILITY IMPROVEMENTS FOR THE CITY OF NIXA, MO BID FORM

SUBSTITUTION ITEMS:

Any manufacturer not listed as an acceptable manufacturer may be listed as a substitution. The substitute equipment must have equivalent characteristics and must meet all the detailed specifications outlined in the contract documents. The Contractor understands that after the contract is awarded, the Owner may select items of any other manufacturer listed by the Contractor in the following tabulation. If awarded the contract, the Contractor agrees to furnish and install any substitutions listed for the price indicated. The prices listed in the following tabulation are “installed” prices and take into consideration any of the changes that may be required. If applicable, the Base Bid would then be adjusted accordingly.

BASE BID EQUIPMENT MANUFACTURERS AND SUBSTITUTIONS

Equipment Item Base Bid Mfg. Substitute Mfg. (Deduct) a Centrifuge and Dewatering Controls FLOTTWEG $ b Centrifuge Feed PC Pump SEEPEX $ c Polymer Feed System FLUID DYNAMICS $ d Conveyor System KWS $

If a contract includes items of equipment of any manufacturer which may require any modification or deviation from the plans, the undersigned agrees to prepare and submit detailed drawings to the Engineer showing all modifications in structures including steel, piping, electrical and mechanical work, required to adapt the plans to the equipment selected. The Bidder further understands that the Engineer will review said detailed drawings of modifications and either approve them or indicate thereon changes necessary to comply with the project requirements. Detail drawings, which are not approved, will be revised then resubmitted to the Engineer.

TOTAL BASE BID PROJECT COST

The following total Base Bid price shall be the basis for the establishment of the apparent low bidder. The following price shall include all costs required for provision of the previously described Items and all work, equipment, mobilization, labor, materials, and other items incidental thereto in order to complete work properly and in accordance with the related contract documents.

Price in Numeric Dollars and Cents: $ .

Price Written in Words:

BF-3 SLUDGE DEWATERING FACILITY IMPROVEMENTS FOR THE CITY OF NIXA, MO BID FORM

AWARD OF CONTRACT

It is intended that one contract will be entered into by the City of Nixa. The lowest responsive, responsible Total Base Bid for the project shall be the basis for the establishment of the apparent low bidder.

Dated on this ______day of ______, 20

SIGNATURE OF BIDDER

If an Individual: ______, doing

business as ______.

If a Partnership: ______

by ______, partner.

If a Corporation: ______

by ______

Title ______(SEAL)

BF-4 DIVISION 11 SECTION 11A- CENTRIFUGE

PART 1 – GENERAL

1.1 SCOPE

Work described in this section includes furnishing labor, equipment, materials, tools and incidentals required for a complete and operable installation of one (1) horizontal decanter centrifuge, centrifuge control panel, operator panel, and related appurtenances. All equipment shall be installed, adjusted, tested, and placed in operation in accordance with these specifications, the manufacturer’s recommendations and as shown on the drawings.

The centrifuge manufacturer shall furnish a programmable logic controller (PLC) capable of controlling the centrifuge unit, support structure for the centrifuge, sludge feed pump, inclined screw conveyor, polymer preparation system and the wash water valves. Sludge feed pumps, electromagnetic flow meter and inclined screw conveyor will be supplied by others.

1.2 DESIGN REQUIREMENTS

A. The equipment shall be suitable for exposure to continuous 95 percent relative humidity conditions and for operation in ambient air temperatures from 40 to 110 degrees F.

B. The sludge to be dewatered will be product of municipal water or wastewater treatment.

C. The unit shall be capable of continuous operation for up to 24 hours per day, seven days per week.

D. The centrifuge shall be optimized for dewatering. In addition, the adjustable pond setting dams may require changing for optimum process capabilities.

E. The design criteria for the centrifuge shall be as follows:

Type of sludge Aerobically Digested Feed concentration, %TS 2% Sludge feed rate, gpm 90-120 Solids loading, lbs/hr 1300 Minimum cake solids, %TS 16-20 Maximum polymer dosage, lbs/ton d.s. 20 Minimum recovery, %SS 90

11A-1

DIVISION 11 SECTION 11A- CENTRIFUGE

1.3 SUBMITTALS

A. Submit drawings and equipment data in accordance with the General Conditions and the following:

1. Equipment Data Sheet 2. Materials of Construction / Abrasion Protection Features 3. Anchor Bolts / Vibration Isolator Detail 4. Standard Instruction Manual 5. Centrifuge Installation Instructions 6. Lubrication and Maintenance Schedule 7. Equipment Shipment / Storage Instructions 8. Spare Parts and Tools List 9. Surface Preparation and Painting Details 10. Sample Factory Test Report 11. Discharge Connection Details 12. Motor Data Sheets 13. Control Panel Drawings 14. Control Panel Bill of Materials 15. Vibration Monitor Details 16. Variable Frequency Drive Details 17. Installation Plan 18. Process & Instrumentation Diagram

B. One (1) sets of operation and maintenance manuals and final as-built drawings to be provided at the completion of the job and in accordance with the General Conditions. One (1) electronic copy of the O&M manual and drawings shall be provided.

1.4 QUALITY ASSURANCE

B. Certificate of Compliance: The manufacturer shall warrant that the centrifuge(s) shall be manufactured in accordance with the Contract Specifications.

C. All manufacturing facilities shall be ISO 9001 certified.

D. The centrifuge manufacturer must have sufficient North American wastewater treatment or potable water installations of similar size and application. The referenced

11A-2

DIVISION 11 SECTION 11A- CENTRIFUGE

installations must demonstrate a history of reliability and service consistent with the current project owner’s expectations. Provide a list of a minimum of four (4) such installations with description, contact names, addresses and telephone numbers with the bid proposal. Failure of a referenced installation to meet these criteria for performance, reliability, and service will be grounds for excluding a manufacturer as an acceptable supplier.

PART 2 – PRODUCTS

2.1 GENERAL DESCRIPTION

The centrifuge shall be a Flottweg C4E-4/454 specifically designed to utilize all new technology. The centrifuge shall be a solid bowl, horizontal, continuous feed, scroll type unit. The centrifuge equipment shall be designed and built to operate continuously or intermittently. The bowl/scroll design shall utilize the conical section for optimal dewatering of the cake solids.

The centrifuge manufacturer shall be responsible for providing a complete centrifuge system, as described herein. The equipment shall be installed by an installing contractor who shall be responsible for off-loading the equipment, providing any temporary storage, and installing the equipment in place. Installation shall include mounting the unit, piping the unit, providing power to the panels and all inter-connected wiring and piping required between the various components.

All equipment specified herein, shall be fabricated, assembled, erected and placed in proper operating condition in full conformity with drawings, specifications, engineering data, instructions, and recommendations of the equipment manufacturer. The centrifuge units shall be the product of suppliers with a minimum of fifty (50) years’ experience in the design and manufacture of centrifuges for water and wastewater applications and shall be specifically designed for the intended conditions of service. Appurtenant equipment shall be new and shall be designed, fabricated and assembled in accordance with the best engineering and shop practices. All facilities shall be ISO 9001 certified. Individual parts shall be manufactured to standard sizes and gauges. Components of the centrifuge shall be designed for the stresses, which may occur during fabrication, shipping, erection or maintenance. Materials shall be suitable for service conditions and as described herein.

The unit shall be completely tested in the manufacturing facility with a standard factory test panel. The equipment shall be shipped in a minimum number of components and they shall typically be comprised of the centrifuge frame, rotating assembly, main drive assembly, control panel, operator panel, and a separate crate of tools and spare parts.

2.2 MATERIALS OF CONSTRUCTION

All wetted parts of the centrifuge rotating assembly shall be a minimum of 316 stainless steel, except for the "O" rings, seals, and abrasion-resistant material. "O" rings shall be Buna-N rubber; lip type seals shall be Buna-N. The feed tube shall be constructed of 316

11A-3

DIVISION 11 SECTION 11A- CENTRIFUGE

stainless steel. The bowl cover shall be of 2 layer stainless steel design with sound insulation. Fiberglass reinforced plastic covers shall not be allowed. The frame and casing shall be fabricated of mild steel. All protective guards shall be constructed of painted carbon steel.

2.3 BOWL

The centrifuge bowl shall be 74" in length, with the inside diameter of 18.5" in the cylindrical section, plus a conical beach extension. The bowl shall be manufactured from centrifugal castings of duplex stainless steel. All centrifugal cast material shall be inspected for cracks, shrinkage, porosity, or other defects, by means of a liquid dye penetrant test. The bowl shell shall be designed to operate at a minimum force of 3650 x G. Fabricated or statically cast bowl shells shall not be allowed.

The front and rear bowl hubs shall be precision cast of duplex stainless steel. The pool depth in the bowl shall be adjustable by use of plate dams at the large diameter end of the bowl. Adjustable weirs should have a means of directing the centrate flow using open vanes in order to recover energy and reduce power consumption. Methods using tubes or similar shapes shall not be accepted. The bowl shall include longitudinal stainless steel wear strips spaced evenly around the inside surface of the bowl. The wear strips shall preclude scroll wear on the bowl casting and provide a sludge layer to improve sludge transportation and prevent bowl erosion. Bowls utilizing grooves shall not be acceptable.

The solids shall be conveyed by the scroll rotating at a positive differential speed. The solids shall be discharged from the bowl via a series of rectangular discharge ports. Each port shall be protected by a field replaceable chilled cast iron bushing. The bushings shall be weight balanced in pairs.

2.4 SCROLL CONVEYOR

The centrifuge shall include a horizontal scroll conveyor equipped with solid helical flights and independently mounted concentrically within the centrifuge bowl. Both the centrifuge bowl and the scroll conveyor shall be independently balanced such that a scroll conveyor can be interchanged with another from the same model centrifuge. The scroll shall utilize a differential speed, which is greater than the bowl speed to convey solids from the cylindrical section to the conical section and out of the bowl with a minimum disturbance to the pool. The edge and the face of the conveyor flights shall be protected by flame-sprayed tungsten carbide or sintered tungsten carbide tiles over the entire length of the conveyor.

2.5 BEARINGS

The centrifuges shall be designed so that the entire rotating assembly is supported by two main pillow block bearings located outside of the process area. Each main bearing shall be grease lubricated ball or cylindrical roller type bearing. Commercially available bearings shall be used. Bearing temperature monitoring shall be included. Seals shall be NBR.

11A-4

DIVISION 11 SECTION 11A- CENTRIFUGE

2.6 FRAME AND CASING The rotating assembly and bearings of the centrifuge shall rest on a mild steel frame, specifically designed for rigidity and noise reduction. Frames containing concrete or other balast materials shall not be allowed. The stainless case shall be designed to act as a protective guard and to provide a complete enclosure for odor containment. The bottom of the casing shall contain flanged connections for sludge cake. The product collection chambers shall be stainless steel with flanges for the sludge cake and centrate discharge. Fiberglass reinforced plastic casings (covers) shall not be allowed.

2.7 DRIVE SYSTEMS

A. MAIN DRIVE SYSTEM

The main drive system shall consist of a 40HP electric motor and a belt drive system. The belt drive system shall consist of multiple V-belts to provide full load capacity and to withstand the full starting torque of the system, with an ABB, Siemens, Eaton, or Schneider 6 pulse variable frequency drive.

The main motor shall be a squirrel cage induction motor and shall be provided with thermal protection. The motor shall have copper windings and be of a high thermal capacity design for operation of 480 / 3 / 60 power. The motor shall have Class F insulation with a B Rise, TEFC, 1.0 service factor, chemical duty, NEMA design A, oversized cast iron terminal box, and continuous duty. The motor temperature shall not exceed 130°C at 90% nameplate voltage. The noise level shall not exceed 84 dbA sound pressure measured at 3 feet from the motor in all directions.

With the motor at ambient temperature, it shall be capable of making two (2) complete starts in succession with coasting to rest between starts. The motor shall also be capable of at least one restart within one hour after any shutdown. The motor bearings shall be grease lubricated, ball or roller anti-friction type of standard manufacture. The bearings shall be conservatively designed to withstand all stresses of the service specified.

B. SCROLL DRIVE SYSTEM

The scroll drive system shall consist of an AC inverter duty motor mounted on the frame and an automatic torque control module incorporated into the variable frequency drive. The scroll drive motor shall be completely independent of the main drive motor allowing operation of the scroll when bowl is stationary. The scroll drive shall be equipped with an approved PWM digital dual quadrant variable frequency drive, with self-tuning. The drive shall have a maximum wire length to motor of 1000 feet.

The centrifuge shall be equipped with a scroll drive system to provide control of the

11A-5

DIVISION 11 SECTION 11A- CENTRIFUGE

differential speed between the centrifuge bowl and conveyor. The scroll drive system shall consist of a multi-stage planetary gear that serves as the drive mechanism and gear reduction between the bowl motor and centrifuge scroll. The gears shall be oil lubricated. The gear shall be independently balanced from the centrifuge and interchangeable. The scroll shall be protected from damage due to high torque overload. A thermal overload protection device in the drive motor shall not be considered as providing for sufficient protection for the scroll drive. The scroll drive shall have a minimum continuous torque rating of 53,000 inch-pounds or 6,000 Nm.

The drive system shall use one motor for the bowl drive and a 10 HP AC motor for the scroll drive. The scroll drive motor shall be a 480/3/60 inverter duty motor.

2.8 NOISE AND VIBRATION

The centrifuge shall be designed such that the average noise level measured at three (3) feet around the periphery of the complete centrifuge assembly shall not exceed 84 dbA when tested at the manufacturing facility without feed and with the inlet and discharges closed. Manufacturers that do not meet the specified noise level must provide a complete sound enclosure with the centrifuge.

The centrifuge, when running without feed, shall be measured for vibration in the manufacturing facility. The vibration velocity shall be less than 11.4 mm/s when measured under dry shop test conditions.

A. VIBRATION ISOLATORS

The centrifuge shall be mounted on rubber-type vibration isolators. The number and vibration constant of the isolator shall be as recommended by the manufacturer for the load and impact resulting from the operation of the centrifuge.

There shall be no rigid connections at the feed tube, vents, solids discharge, liquid discharge or other components whatsoever to the machine, thus preventing transmission of vibration to structure, piping and appurtenant equipment.

B. FLEXIBLE CONNECTORS To ensure a quiet installation, flexible connectors shall be provided to isolate the centrifuge from the building structure. The solids and centrate chutes shall be equipped with 304 stainless steel backup flanges. All hardware shall be supplied by the installing contractor. Flexible pipe connections shall be supplied for the sludge feed line, polymer connection and frame drain. All flexible connections shall be flanged for simple connection to associated piping.

Due to local conditions, flexible connectors for the main drive motor, scroll drive motor and centrifuge junction boxes must be furnished by the installing contractor,

11A-6

DIVISION 11 SECTION 11A- CENTRIFUGE

such that all local electrical codes are met.

C. VIBRATION MONITORING

The centrifuge shall be equipped with a vibration monitoring system consisting of an accelerometer, with 4-20 mAmp output, and dry contact for shutdown alarm

Upon reaching an alert (stage 1) alarm, the control system will issue a warning alarm at the panel. Upon reaching a danger alarm (stage 2), the control system will shut down the centrifuge in a controlled shut down sequence.

2.9 LUBRICATION

The two main pillow block bearings on the centrifuge and the gears shall be grease lubricated. The scroll bearings shall be sealed and permanently grease lubricated.

2.10 GUARDS

Guards for all rotating components, gearboxes and belt drives shall be a minimum 16 gauge stainless steel and shall be designed to OSHA standards. Completely enclose the entire belt drive system and construct to minimize noise and vibration. Guards manufactured from carbon steel or fiberglass reinforced plastic shall not be allowed.

2.11 ANCHOR BOLTS

Anchor bolts shall be supplied by the installing contractor.

2.12 STANDARD TOOLS AND ACCESSORIES

A. One set of standard tools shall be provided to disassemble and re-assemble the centrifuge as required. B. The following tools shall be supplied as a minimum:

1. One Belt Tensioning Device 2. One set of lifting straps for lifting the machine housing 3. One complete set of threaded spindles and plates used for disassembling and assembling close tolerance parts

C. Provide one year’s supply of lubricants.

11A-7

DIVISION 11 SECTION 11A- CENTRIFUGE

2.13 INSTRUMENTATION AND CONTROLS

A. GENERAL

1. The centrifuge control system shall have a PLC and an Operator Interface Terminal (OIT). The control system shall be designed to work in manual and automatic modes. Should a disruption occur, the centrifuge monitoring system shall indicate the cause with a first out sequence and define the interruption. The interlock must be reset in order to continue.

2. The scroll drive is controlled by the automatic torque control module which controls differential speed in the manual mode and torque in the automatic mode. The torque control module is integral to the PLC and OIT. In the automatic torque mode, scroll drive speed is automatically adjusted to maintain constant torque, thereby compensating for varying feed characteristics while optimizing residence time and separation. The OIT provides digital display of bowl speed, differential speed and torque. Set points for the differential speed, torque, gradient, etc… are entered via a numeric keypad on the OIT.

B. CENTRIFUGE CONTROL PANEL

NEMA 4X double-door free-standing air-conditioned mounted stainless steel enclosure. Included in the enclosure shall be a through–the–door operated main disconnect that can be locked in the off position. The enclosure shall have lifting eyes and can be arranged to have top or bottom conduit entry. The enclosure shall also have a pad-lockable disconnect switch with a main fused distribution block which 65kA interrupting capacity. A 6 pulse main drive VFD, 6 pulse scroll drive VFD, and industrial hardware components shall also be in the enclosure. An Allen-Bradley CompactLogix shall be supplied and programmed to operate any and all necessary sequences. Included shall be a centrifuge automatic torque control module that shall maintain process optimization within adjustable preset limitations and operate in differential speed and torque modes. A 10” Allen-Bradley Panelview shall be provided. An alarm acknowledge and alarm silence shall be integral to the OIT. All pushbuttons and pilot lights shall be water-tight and corrosion resistant. The OIT shall be utilized for major operational adjustments. The OIT shall display fault messages with actual time and date. All components in the control panel shall be completely factory wired. All external control connection points shall terminate on a terminal strip. There shall be a minimum of 10% spare terminal connections supplied. The PLC shall be capable of interfacing via Ethernet to SCADA systems. Included within the control panel shall be a safety emergency stop relay and an hour meter. An emergency stop pushbutton, alarm horn, folding shelf, and an interface with a convenience outlet and Ethernet connection shall be provided on the exterior of the enclosure. This enclosure shall be illuminated using 24 VDC LED lighting.

C. REMOTE CONNECTIVITY

11A-8

DIVISION 11 SECTION 11A- CENTRIFUGE

An Ewon Cosy, Ewon Flexy, or Phoenix Contact Mguard Ethernet switch shall be provided by the manufacturer as part of the control system to allow for a direct remote connection to the control components (PLC and HMI) from the manufacturer’s headquarters in order to complete timely simple program changes.

D. REDUNDANT CONTROL POWER SUPPLIES

In order to continue processing during a short power interruption, loss of 480 VAC should be detected by instrumentation. If the duration of the interruption is less than 3 seconds, a warning should appear on the OIT and the machine should continue normal operation. If the duration of the interruption exceeds 3 seconds, a shutdown alarm shall appear and a semi- controlled shutdown sequence shall be initiated. The centrifuge system shall provide for an immediate restart by the operator once power is restored. With the centrifuge operating at full speed, the control system shall remain powered up for a minimum of 15 minutes after 480 VAC power is lost.

As part of this system, redundant power supplies with a diode module shall be provided. A 120 VAC/24 VDC power supply and a 650 VDC/24 VDC power supply with Sitop redundancy module, all manufactured by Siemens, shall be used to ensure proper operation.

PART 3 – EXECUTION

3.1 FACTORY TESTING

Factory testing of the centrifuge shall be performed at the centrifuge manufacturer’s facility to demonstrate the absence of mechanical or electrical defects and that the centrifuge operates within the specified limits. Factory testing of the control and power panels shall be at the panel fabrication facility.

A. Shop Testing Procedure

1. Centrifuge manufacturer shall allow inspection and witness of the shop test of the equipment by the Engineer. 2. Equipment to be shop tested and witnessed by the Engineer shall include: a. Centrifuge b. Control Panel and Operator Panel (to be tested at point of manufacture). 3. Centrifuge manufacturer shall notify Engineer of the test schedule not less than 14 days in advance. 4. Test conditions:The following tests shall be completed before the centrifuge is released for shipment. a. Vibration measurement with bowl empty.

11A-9

DIVISION 11 SECTION 11A- CENTRIFUGE

b. Vibration measurement with bowl filled with water. c. Operation of machine for several hours with water. d. Motor starting amperage. e. Test equipment/procedures: a) Test equipment shall be calibrated. b) Unit and control system shall be tested with a simulation panel. c) All circuits shall be checked and all alarms and shutdown conditions simulated to check the alarm circuits. 5. Certified test results shall be submitted after completion.

3.2 FIELD MECHANICAL TESTING

Field testing of the centrifuge shall be performed to demonstrate the equipment was not damaged during storage, transportation, or installation. Also, that the equipment is properly installed and aligned, and that there are no mechanical defects in any parts. The proper interaction of the centrifuge, drive motor, scroll drive, and control panel will also be demonstrated.

The test procedure, submitted by the manufacturer and approved by the Engineer or Owner, shall be run by a qualified representative of the centrifuge manufacturer in the presence of the Owner and/or Engineer.

It shall be the Owner’s responsibility to make sure that qualified technical representatives from the suppliers of all ancillary equipment be present during this test period to demonstrate the proper interaction of their equipment with the centrifuge. The Owner shall be responsible for delays in testing due to non-availability of personnel, services, or utilities.

The field tests shall consist of a two-hour dry run of the centrifuge followed by a four-hour wet run of the centrifuge together with the polymer system, sludge feed system, washwater system, cake conveyance equipment, and associated instrumentation and controls.

A. Field Testing Procedure

1. Field Inspection

The centrifuge manufacturer will inspect the final installation and supervise the field acceptance tests of the equipment.

2. Functional Test

a. Functional testing shall be conducted after the installation of the centrifuge and all appurtenances and the equipment has been operated a sufficient period to make any corrections or adjustments. The complete unit shall be subject to field acceptance tests under actual operating conditions to

11A-10

DIVISION 11 SECTION 11A- CENTRIFUGE

determine that operation is satisfactory. b. The functional test shall be made under the direct supervision of the centrifuge manufacturer and in the presence of the Engineer. c. The functional test shall determine the characteristics of the unit and shall demonstrate that under all conditions of operation the unit: i. Has not been damaged by transportation ii. Has been properly installed. iii. Has no mechanical defects. iv. Is in proper alignment. v. Has been properly connected. vi. Is free of overheating of any parts. vii. Is free of objectionable vibration. viii. Is free of overloading of any parts. d. Prior to acceptance, the centrifuge manufacturer shall operate the centrifuge for a one day 6 hour per day period under actual conditions with sludge from the Owner’s facility.

3. Vibration Test

The centrifuge manufacturer shall verify operations are within tolerances.

4. Acceptance Test a. After satisfactory completion of the functional start-up test and after the Engineer has agreed that all ancillary equipment both upstream and downstream of the centrifuges is in satisfactory operating condition, an acceptance test shall be conducted using representative sludge. b. Prior to testing, the Contractor shall supply the manufacturer with sufficient quantities of representative sludge to conduct bench scale testing of polymers. Based upon the test result, the centrifuge manufacturer shall recommend the polymer for use in acceptance testing. c. The Contractor shall furnish all operating and support personnel, power, water, chemicals, heat and all other incidentals required to take samples and perform the tests. The Contractor shall be responsible for collecting all required samples and measurements. The Owner shall be responsible for supplying all polymers. d. The centrifuge shall be fed representative sludge and polymer in a proportion recommended by the centrifuge manufacturer. The acceptance test shall demonstrate satisfactory operation of all equipment, controls, interlocks and alarms. The unit shall operate continuously, trouble free, for a minimum of three 6-hour periods on three separate days.

3.3 FIELD PROCESS PERFORMANCE TESTING

A. After satisfactory completion of acceptance tests conducted on the centrifuge, the centrifuge shall be tested for three (3), 4-hour periods to determine acceptable performance in accordance with the Design Requirements .

11A-11

DIVISION 11 SECTION 11A- CENTRIFUGE

B. The unit shall be fed representative sludge and polymer during which the average performance of the unit must equal or exceed the design performance parameters.

B. During each day’s performance test, the Contractor shall be responsible for collecting all required samples and measurements at 1-hour intervals in order to make the following determinations. The first set of samples and measurements shall be taken 1 hour after the beginning of the test run.

1. Sludge feed – total solids. 2. Centrate - total solids. 3. Centrate – suspended solids. 4. Final cake discharge – total solids. 5. Plant water (one or two daily composites) – total solids. 6. Polymer feed rate - gallons per minute. 7. Sludge feed rate – gallons per minute. 8. Solids capture – percent. 9. Setting for polymer feed pump. 10. Setting for sludge feed pump. 11. Differential speed. 12. Motor amperage. 13. Sludge feed – percent volatile solids. 14. Sludge feed – SVI

D. During the entire Performance Test period, all laboratory analyses shall be performed by the Owner.

E. All data collected during performance tests shall be made available for the Engineer for determining compliance with the Specifications.

F. The average values of the tests conducted shall meet or exceed the performance criteria.

G. Polymer dosage shall be determined as the total active polymer consumed divided by the dry solids fed to the machine.

H. Test data that are in apparent error shall be discarded.

I. In the event the equipment is not meeting the guaranteed performance, the manufacturer shall, at his own expense modify the equipment to meet these standards.

J. The equipment shall be modified and the test repeated until successfully completed, or one year has elapsed since the failure of the first attempted performance test.

11A-12

DIVISION 11 SECTION 11A- CENTRIFUGE

3.4 TECHNICAL SERVICES

Technical Services of the manufacturer’s representative shall be supplied in the following areas:

A. Five (5) days to confirm proper installation, alignment, mechanical start-up, and field mechanical.

B. Five (5) days for process start-up, training and field process performance testing.

C. For every five (5) days of time allotted to the project, one trip shall be included. One trip shall consist of the associated expenses of airfare and carfare, plus accommodations and meals. Additional days shall be billable in accordance with the standard rate schedule.

11A-13

DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

PART 1: GENERAL

1.1 SCOPE OF WORK

The Biosolids Conveyance System described shall be from a single shaftless screw conveyor Manufacturer (i.e. not an agent, reseller or supplier), complete with all necessary components, drives, motors, ancillary items and supports, including providing required support at the discharge end of the conveyor. Interconnecting chutes between screw conveyors shall be provided by the Manufacturer so that a complete screw conveyor system, from the point of receiving biosolids to the final discharge point, is supplied by a single manufacturer (hereinafter the Manufacturer).

The design of the shaftless screw conveyor system shall be based upon the Contract Drawings, these Specifications and the Manufacturer’s experience whose designated Project Manager must have had direct responsibility for design, manufacture and commissioning of at least ten (10) systems of similar sizes, capacities and material with similar characteristics, operating for a minimum of five (5) years.

The Contract Drawings and this Section provide equipment descriptions, minimum requirements and mandatory features of the equipment to be furnished. It is the Manufacturer’s responsibility to design and furnish the equipment complete in all details, performance and reliability meeting the requirements and intent of the Contract Drawings and these specifications.

1.2 SUBMITTALS

A. General:

1. All data and drawings to be provided in Imperial system. Any metric dimensions must be clearly noted and marked with an Imperial equivalent. 2. Data sheets with description of the proposed equipment, size, length, type, capacity, arrangement, materials of construction, motor size, motor type, motor power requirements and equipment weight. 3. List of components and accessories to be furnished with catalog information. 4. Significant dimensional differences between the equipment specified herein, indicated on the Drawings and the proposed equipment.

B. Design Calculations:

1. Submit certified capacity, power and elongation calculations for the screw conveyor and spiral, respectively. 2. Submit certified torsional analysis for the conveyor drive shaft. 3. Submit structural calculations for the conveyor supports stamped by an Engineer certified to practice in the State in which the equipment will be

11B-1 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR 4. service.

5. Submit bearing life calculations for the gear reducer bearings and/or drive end bearings. 6. Design loadings to be transmitted to foundations or supports. C. Shop Drawings:

1. Drawings and specifications for components of the equipment, showing principal dimensions and parts, materials of construction, material thicknesses. 2. Screw diameter, pitch, rotational speed and torque tube diameter. 3. Equipment performance specifications. 4. Drive details, including service factor of gear reducer based on absorbed horsepower and installed motor horsepower. 5. Size and location of anchor bolts or attachments to the foundations or supports.

D. Quality Assurance and Control Submittals:

1.3 Quality Assurance and Control Submittals:

1. Manufacturer must be ISO 9001:2000 certified or submit a full Quality Plan for approval by the Engineer prior to award of Contract. Quality Plan must include a description of the processes to be used which are equivalent to ISO 9001:2000. The manufacturer is responsible for the full costs (i.e. travel and expenses) for two (2) of the Design Consultants representatives to visit the facility where the Equipment will be manufactured to review the Quality Plan and a separate trip to inspect the finished product prior to shipping.

2. Submit Project Manager’s qualifications with references.

3. Manufacturer’s Certificate of Compliance, including performance guarantee.

4. Operation and maintenance manuals, including recommended maintenance schedule.

5. Special shipping, storage, protection and handling instructions.

6. Manufacturer’s installation instructions.

7. Manufacturer’s Certificate of Proper Installation.

11B-2 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

PART 2: PRODUCTS

2.1 MANUFACTURERS

A. Equipment Systems specified in this Section shall be product of:

1. KWS Environmental Inc. 2. Pre-approved equal 2.2 2.3 GENERAL REQUIREMENTS

A. Fasteners:

All fasteners and grease fittings shall be Imperial sizing. Metric fasteners and fittings shall not be used.

B. Welding:

Except as otherwise indicated, welding shall comply with ANSI/AWWA D100 and AWWA C206, and the following:

1. Welding shall be by the metal-arc method or gas-shielded arc method described in the American Welding Society’s “Welding Handbook” as supplemented by other AWS standards. Qualification of welders shall comply with AWS Standard AWS D1.198. 2. In assembly and during welding, the component parts shall be clamped, supported and restrained to minimize distortion and for control of dimensions. Weld reinforcement shall comply with the AWS code. Upon completion of welding, weld splatter, flux, slag and burrs left by attachments shall be removed. Welds shall be repaired to produce a workmanlike appearance with uniform weld contours and dimensions. Sharp corners of material which is to be painted or coated shall be ground to a minimum of 1/32” on the flat.

C. Safety Devices:

The completed work shall include all necessary permanent safety devices, such as machinery guards and similar items as required by OSHA and other federal, state and local health and safety regulations. Conveyors shall be equipped with emergency stop pullcords.

11B-3 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

D. Flanges and Pipe Threads:

Flanges on equipment shall comply with ANSI B16.1, Class 125 or B16.5, Class 150, unless otherwise indicated. Threaded flanges and fittings shall have standard taper pipe threads complying with ANSI/ASME B1.20.1. Metric flanges, piping and threads shall not be used.

E. Nameplates:

Equipment nameplates shall be fastened to the equipment in accessible. Nameplates shall contain the Manufacturer’s name and telephone number for service.

F. Bearings:

1. Bearings shall conform to the standards of the Anti-Friction Bearing Manufacturers Association, Inc. (AFBMA). 2. Except where otherwise indicated, bearings of process equipment shall have a minimum B-10 life expectancy of 50,000 hours.

2.4 SERVICE CONDITIONS

A. Material:

1 Type of sludge: Aerobically Digested 2 Material density - max: 60 lbs/ ft3 3 Material density – min 50 lbs/ ft3 4 Solids, percent by weight 2% % 5 Capacity (max): 4.8 wet tons/hour(tph) 6 Capacity (max): 160 ft3 / hour 7 Ambient temperature: 67 F maximum 8 Ambient temperature: 45 F minimum

B. Physical Requirements: 1. Screw Conveyor:

Conveyor Qty Screw Nominal Incline Hp Number Tag No. Diameter – Min Length (degrees) (min) Gates (inches) (feet- inches) SSC-12 1 12 16’-0” 22 5 0

11B-4 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR Service Duty:

1. Number of hours per day: 2. Number of days per week: 3. Number starts per hour (max):

C. Start-up:

24 7 2

Screw conveyor must be able to start when loaded to 150% of the maximum capacity with wet sludge described under Clause 2.3.A.

D. Design Capacity:

The screw conveyor shall be designed to operate continuously under the specified operating conditions with peak loads of up to 150% without damage or significantly reduced service life.

2.5 COMPONENTS

A. Materials:

1. Trough cover and end plates: Type 304 stainless steel. 2. Inlets/outlets: Type 304 stainless steel. 3. Spiral Flighting: Special Alloy Bar Steel, 340 Brinnel Hardness. 4. Wear Liner: Xylethon/UHMW per ASTM D4020 with a minimum molecular weight of 3 million and a minimum thickness of 1/2". Liner will be a laminate with 3/8” Durawear Xylethon, extra tough layer (grey) and 1/8” thick white layer. 5. Supports: Type 304 stainless steel. 6. Drive shaft: C 1045 steel. 7. Gaskets: neoprene durometer 50.

B. Troughs:

1. Troughs shall conform to the dimensional standards of CEMA 300 and enclosure classification IIE and shall be U-shaped. 2. Fabricated from minimum 3/16” plate and minimum 3/16” thick flat bar top flanges. Top flanges shall be formed or welded in place to the trough.

11B-5 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR 3. Single welded piece for lengths up to 12 feet. Troughs longer than 18 feet shall be constructed of two or more sections bolted together at the trough 4. joining flanges. 5. Glue neoprene (minimum 1/8” thick) gasket over full face of flanges (on one flange face only for adjoining flanges). 6. Fabricate trough drive end from 3/8" steel plates and non-drive end from ¼” steel plates bolted across ends of the trough. Fabricate drive and non-drive support ends from the same material. These assemblies to be welded to the screw conveyor trough end plates (or may be bolted to the trough end plate using a matching 3/8” thick mounting plate). 7. Conveyor troughs to be complete with saddle-type supports shaped to the profile of the screw conveyor trough and extending to a common fixed distance below the centerline of the screw (not greater than 12 feet center-to- center). Include separate support points under the drive end assembly and end shaft assembly. These to be welded as an integral part of these assemblies using 3/8” plate. 8. Each screw conveyor trough to be complete with a 4” NPT diameter drain nipple extending three inches below the screw conveyor trough, with a threaded cap, located at the low point of trough.

C. Covers:

1. Fabricated from 12 gauge material, single-piece formed steel plate with turned down edges parallel to the sides of the trough flange. 2. Not to exceed 48” each in length. 3. The cover sections are to be attached to the trough flange utilizing hex head bolts or hinged on one side and with quick-connect clamp fittings on the other side. If cover may be opened without tools, an expanded mesh screen must be installed the full length of the conveyor 4. Foul air connections shall be of a size and location as shown on the contract documents.

D. Inlets/Outlets:

1. Fabricated from a minimum of 3/16” thick plate.

11B-6 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

E. Spirals:

1. Spiral shall be cold formed in a continuous process from a minimum of 20’ long bar sections with a minimum of 340 BHN and a tensile strength of at least 120,000 psi. 2. Spirals shall consist of an outer spiral and, where recommended by the Manufacturer, an inner spiral. 3. Spiral pitch shall be consistent to within +/- 2% of the nominal pitch. 4. Spiral outside diameter shall be consistent to within + 0” and – 1/8”. 5. Where applicable, inner and outer spirals shall be stitch welded in accordance with AWS welding guidelines and shall be sufficient to ensure structural integrity under 150% load conditions. Spiral elongation under such load conditions shall be less than 0.03” per foot of spiral. 6. The total axial load, established as 150% of the design load shall be less than 40% of the spiral(s) Fy.

F. Holddown Provisions:

1. Holddown provisions shall be provided as recommended by the manufacturer to secure spiral flighting in trough bottom. 2. Holddowns shall be bolted to trough and design shall not impede material flow. 3. As a minimum, holddown shall be provided every 10 pitches of spiral length and each holddown shall span 1.5 pitches as a minimum. 4. Holddown provisions shall not require regular maintenance and any wear component shall have a life greater than or equal to the life of the trough liner.

G. Lubrication System for Drive End Bearing:

1. Bearings shall be equipped with a spring-loaded lubricator assembly. The lubricator shall be mounted above each intermediate bearing location. The spring-loaded lubricator reservoir shall be transparent with 6 oz. capacity. Each lubricator shall be equipped with a metal base complete with base coupling, piston with O-rings, compression springs and filling connections.

H. Drive Assembly, End Shaft Assembly:

1. Drive and end shaft assemblies to consist of the following separate components: a. Drive assembly: i. drive shaft; ii. packing gland; iii. hollow shaft gear reducer; iv. C-face adaptor and motor.

11B-7 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

2. Shafts to be complete with flanged ends and mating bolt holes to match the conveyor spiral flanged end plates. Shaft to be integral with the shaft flange as a single-piece. Shafts welded to a flange are not acceptable. 3. Adjustable packing gland seal shall be provided where drive shaft project through conveyor end plate. Packing glands to be complete with not less than three packing rings per stuffingbox where sealing is critical and as determined by the Manufacturer. Provide grease fitting to lubricate the packing rings. 4. Outside support bearings, except where flange mounted gear reducers are used, to be SKF or Dodge spherical roller bearings, mounted in pillow block bearing houses. Mount bearing outboard of the packing gland assembly with sufficient clearance to permit removal of stuffingbox bolts, cover and repacking without having to remove the bearing housing or bearing from the housing. Fit each bearing housing with a grease nipple, with escape release provisions. 5. Except where shaft-mounted gear reducers are being used, flexible couplings shall separate drive shaft from gear reducer. Coupling to consist of two cast iron hub rings separated by synthetic elastomer bushes that absorb the misalignment that may occur between the screw conveyor drive shaft and the gear reducer shaft, as well as absorb shock loads. 6. Gear reducers to be parallel helical or bevel helical, 2, 3 or 4-stage gear reducers for shaft-mounted or foot-mounted, with flexible coupling. Gear reducers to be Eurodrive, Dodge, Nord or Flender. 7. Size gear reducers and flexible couplings based on the input power to each gear reducer, with the resulting torque calculated at the output shaft rpm, with a safety factor of 1.5 times this calculated torque. The nominal rated output torque (AGMA 2) to be greater than or equal to the calculated output torque and its safety factors. A second criteria to be met is that the nominal rated output torque must exceed the electric motor nameplate horsepower equivalent torque at the gear reducer output shaft rpm. 8. Oil level indicator and drain locations shall be readily accessible. 9. Drive connections between motor and gearbox shall be sized based on the electric motor drive horsepower with a safety factor of 1.5 times the horsepower of the electric motor drive. 10. Gearboxes and motors shall be factory-assembled on the conveyor, factory- tested and shipped fully assembled with the conveyors.

I. Motors and Drives:

1. Provide squirrel-cage AC induction motors that meet all applicable requirements of NEMA standards. Load on motor shall not exceed nameplate horsepower rating under any anticipated load condition. 2. In addition, the motors shall meet the following specific requirements: a. Voltage rating: 460 volts (or 230/460), 3 ph, 60 Hz; b. Efficiency: premium;

11B-8 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

c. Service factor: 1.15; d. Speed: 1800 rpm, constant; e. Enclosure: TEFC; f. Mounting: flanged or foot-mounted.

J. Conveyor Supports:

1. Saddle-type supports shall be shaped to the profile of the conveyor trough and shall be designed for welding to the trough in the field after final positioning. Supports shall extend to a common fixed distance below the centerline of the screw and be spaced at 12-foot centers maximum. 2. The drive and end shaft assemblies shall have integrally welded supports constructed of 3/8” thick plates. Each support shall have a minimum of two predrilled holes for attachment to the building structure. 3. Support loads are to be based on completely filled trough, weight of the conveyor and dynamic loading when operating. 4. Coordinate support locations with facility structure. Access to other process systems shall not be restricted by the supports. 5. Shim each conveyor support in field as required to conform to Manufacturer’s installation tolerances.

K. Chutes:

1. Provide chutes for connections between conveyors. Chutes shall be fabricated from minimum 3/16” thick, Type 304 stainless steel. Connection flanges shall be ¼” x 2- 3/4”. Flanged connections shall be provided on the underside of the conveyor troughs at the drop point. Flanges shall be located approximately 3” below the bottom of the conveyor trough. 2. Drop chutes longer than 2 feet between connection flanges shall include gasketed flanges and at least four handles shall be provided on each chute section to facilitate removal. Handles shall be ½” diameter rod, of the same material as the chute, formed and welded to the sides of the section. 3. Furnish 1/8” thick, full-face neoprene gasket for installation between each flanged connection and transition chute.

2.6 ACCESSORIES

A. Motion Switches:

1. Provide non-contacting, proximity-type speed switch on each conveyor for detecting zero speed condition on monitored equipment consisting of a sensor/pre-amplifier and an amplifier/output switch unit. 2. The sensor/pre-amplifier shall utilize magnetic proximity effect to detect

11B-9 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

equipment rotational speed without physical connection to the rotating equipment. Sensors shall provide output pulses in proportion to rotational speed by detection of a ferrous target mounted on the rotating equipment. The sensor shall operate satisfactorily with air gaps of up to 4”. Provide sensor/pre-amplifier complete with mounting flange, threaded body and locknut. 3. The amplifier/output switch unit shall provide two single-pole, double-throw contacts that operate on underspeed detection. Provide dry contact outputs rated for 5 amps at 120 volts AC. The unit shall include an adjustable start-up delay of 0 to 60 seconds to override zero speed alarm during initial acceleration. Units shall operate on 120 volt AC power. Provide set point adjustment range of 2 to 3,000 pulses per minute. Zero speed switch shall be Milltronics MFA-4p with MSP-12 sensor/pre- amplifier. The MFA-4p shall be contained in a NEMA 4X enclosure and mounted to a wall or support (by others). 4. All motion switches shall have NEMA 4X enclosures.

B. Safety Pullwires/Switches:

1. Provide Safety Pullwires and Pullwire Switches on the cover opening side of horizontal and inclined conveyors.

a. Provide where shown on the Electrical Drawings. b. Pullwires: Stainless steel aircraft cable in orange-coated vinyl covering 3/16" O.D.

c. Pullwire Switches: Indicating, manually reset type, SPDT switches, NEMA 4, rate 20A at 125 V.

d. Switch Manufacturer: Model RS by Conveyor Components.

2.7 SLIDE GATES

A. Slide gates shall be pneumatically operated as indicated on the drawings. Gates shall be complete with actuators. The requirements of each slide gate shall include:

1. Construction shall be of carbon steel channel, angle and plate. All welding per AWS Standards. 2. Gates shall be X” x X” minimum opening. 3. Gate blade shall be constructed of Type 316 stainless steel.

11B-10 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

4. Gate blade shall be supported on 1¼” stainless steel rollers which are located out of the material flow. Rollers include bronze bushings and require no lubrication. 5. Gate blade leading edge shall be beveled to facilitate its travel through material being handled. 6. All product contact surfaces shall be Type 304 stainless steel. 7. Gate wiping seals shall be made of UHMW. Seals contact the top of the gate blade along the perimeter of the throat opening. Seals are retained by a bolted steel bar which forms the inlet throat lining of the slide gate. 8. Actuation shall be by: i. AUMA Matic Model SA10.1(54A) Electric Actuator or equal ii. NEMA 4X enclosure iii. 460/3/60 power iv. Output speed 54 rpm v. Max torque 88 ft-lbs vi. Stem acceptance 1.25" Dia. vii. Torque and limit switches viii. Four gear train limit switch ix. Manual handwheel override x. Integral reversing starter and 24VDC control transformer xi. Open/stop/close push buttons xii. Local/off/remote selector switch, padlock able indicating lights 9. The retract blade area shall have expanded metal guard above and below blade.

2.8 CONTROLS

A. The Screw Conveyor with slide gates will supplied with one (1) local control panel with the following minimum features:

1. NEMA 4X enclosure 2. H-O-A (hand-off-auto) selector switch 3. Start and Stop pushbuttons – NEMA 4X (conveyor) 4. Open and Close pushbuttons – NEMA 4X (slide gates) 5. Status light (LED) – Conveyor 6. Status lights (LED) - Gates 7. Flanged disconnect with lockout provision 8. Motor starter sized for the conveyor 9. Torque Overload device with fault indication on the panel 10. Power transformer for 120V control power 11. Fuses, as required

B. The automatic controls for the Equipment, if any in this Section will be provided by OTHERS.

11B-11 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

2.9 FACTORY-APPLIED PROTECTIVE COATINGS

A. Exterior Surface Preparation and Protective Coating:

For exterior ferrous components, except drive, and all stainless steel surfaces, sandblast all ferrous steel surfaces to SSPC-SP-6. Factory-apply one coat of primer 2.0 dry film thickness. Final field painting and touch-up to be applied by installing contractor after installation and as specified in Section 09900.

B. Stainless Steel Surfaces:

Glassblast all exterior stainless steel surfaces only to a uniform finish.

C. Gearboxes, motors, bearings, etc. are to be supplied in Manufacturer’s standard enamel finish.

2.10 SPARE PARTS - OPTIONAL

Manufacturer must have spare parts inventory within the continental USA and must be able to respond to spare parts requirements within thirty (30) days.

One (1) set of slide gate seals, as applicable One (1) set of packing material for each. One (1) set of trough liner material for all conveyors. One (1) motor of each size

One (1) gear reducer of each size One (1) pushbutton of each type used One (1) set of fuses of each size used

2.11 FACTORY ASSEMBLY AND TESTING

A. Completely shop-assemble with drive prior to shipment and run under no load for a minimum of 15 minutes to ensure proper operation. Provide a signed shop test certificate and record amperage on motor.

B. Inspect equipment and test for proper alignment, quiet operation, proper connection and satisfactory performance of components. Match-mark any sections which have to be disassembled for the purposes of shipping. C. 11B-12 DIVISION 11 SECTION 11B-DEWATERED SLUDGE CONVEYOR

2.12 SITE SERVICES

Manufacturer to provide the following site services, using a licensed and factory-trained service technician:

Supervision of installation 1 trips of 1 days

Commissioning and operator 1 trips of 1 days training

11B-13