MECHANICALLY CLEANED FINE SCREENS

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MECHANICALLY CLEANED FINE SCREENS

PART 1          GENERAL

1.01       WORK OF THIS SECTION

A.     The Work of this Section includes providing all labor, material, equipment, equipment supports,
         coordination, documentation, instrumentation and controls, factory and field testing, and training of
         Owner personnel for a complete and operational mechanically cleaned fine screen system.

1.02       REFERENCES

A.     The following is a list of standards which may be referenced in this Section:

1.      American Bearing Manufacturers’ Association (ABMA): 11, Load Ratings and Fatigue Life for Roller
         Bearings.
2.      American Gear Manufacturers Association (AGMA):
         a.      2015-1-A01, Accuracy Classification System – Tangential Measurements for Cylindrical Gears.
         b.      6034-B92, Practice for Enclosed Cylindrical Wormgear Speed Reducers and Gearmotors.
         c.      9005-E02, Industrial Gear Lubrication.
3.      American Welding Society (AWS):
         a.      D1.1/D1.1M, Structural Welding Code – Steel.
         b.      QC 1, Standard for AWS Certification of Welding Inspectors.
4.      Anti Friction Bearing Manufacturers Association (AFBMA):
         a.      Standard 9-90, Load Ratings and Fatigue Life for Ball Bearings.
         b.      Standard 11-90, Load Ratings and Fatigue Life for Roller Bearings.
5.      ASTM International (ASTM):
         a.      A322, Standard Specification for Steel Bars, Alloy, Standard Grades.
         b.      A380, Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts,
                  Equipment, and Systems.
         c.      A480/A480M, General Requirements for Flat-Rolled Stainless and Heat-Resisting Steelplate,
                  Sheet, and Strip.
         d.      A507-10, Standard Specification for Drawing Alloy Steel, Sheet and Strip, Hot-Rolled and
                  Cold-Rolled.
         e.      C582, Standard Specification for Contact-Molded Reinforced Thermosetting Plastic (RTP)
                  Laminates for Corrosion-Resistant Equipment.
         f.       D3917, Standard Specification for Dimensional Tolerance of Thermosetting Glass-Reinforced
                  Plastics Pultruded Shapes.
6.      National Electrical Code (NEC).
7.      National Electrical Manufacturers’ Association (NEMA): MG 1, Motors and Generators.
8.      National Fire Protection Association (NFPA): 820, Standard for Fire Protection in Wastewater
         Treatment and Collection Facilities.
9.      Underwriters Laboratory (UL): 674, Electric Motors and Generators for Use in Division 1 Hazardous
         (Classified) Locations.

1.03       SUBMITTALS

A.     Provide action and informational submittals in accordance with Section XXXXX, Submittal
         Procedures, and as identified herein.

B.     Action Submittals:
1.      Shop Drawings:
         a.      Manufacturer’s catalog information, descriptive literature, specifications, equipment weight, lifting
                  points, and identification of materials for construction.
         b.      Detailed structural, mechanical, and electrical drawings showing equipment fabrications and
                  interface with other items.
         c.      Dimensions, size, and locations of connections to other work.
         d.      Details of attachment and support.
         e.      Gear output torque and rake weight lifting capacity calculations.
         f.       Complete motor nameplate data, as defined by NEMA, motor manufacturer, and motor
                  modifications. See Section XXXXX, Low-Voltage AC Induction Motors, for motor submittal
                  requirements.
         g.      Control Panel elevation drawings showing construction and placement of operator interface
                  devices and other elements.
         h.      Power and control wiring diagrams, including terminals and numbers.
         i.       See Section 40 99 90, Package Control Systems, for additional submittal requirements.
         j.       Shop painting systems, including manufacturer’s descriptive technical catalog literature and
                  specifications.
         k.      External utility requirements for air, water, power, drain, etc., for each component, including
                  pressure and flow rate.
         l.       Drawings of equipment enclosures designed and stamped by professional structural engineer.
        m.     Anchorage and bracing data sheets and drawings as required by Section XXXXX, Anchorage
                 and Bracing.

C.     Informational Submittals:
1.      Statement of Qualification: Professional structural engineer.
2.      Manufacturer’s Certificate of Compliance of factory-applied coating system.
3.      Manufacturer’s installation instructions.
4.      Special shipping, storage and protection, and handling instructions.
5.      Written factory test report of inspection.
6.      Manufacturer’s Certificate of Proper Installation in accordance with Section XXXX, Manufacturers’
         Field Services.
7.      Field functional test reports.
8.      Manufacturer’s warranty.
9.      Operation and Maintenance Data: As specified in Section XXXX, Operation and Maintenance
         Data, including routine maintenance requirements prior to plant startup.
10.    Welder/welding operator qualifications.
11.    Welding inspector credentials.
12.    Welding Inspector’s Report.

1.04       QUALIFICATIONS

A.     Registered Professional Structural Engineer.

B.     Welder/Welding Operator: In accordance with AWS D1.1/D1.1M.

C.     Welding Inspector: Certified in accordance with AWS QC 1, and having prior experience with welding
         codes specified.

1.05       EXTRA MATERIALS

A.     Provide recommended list of spare parts in the Operations and Maintenance Manual, in accordance
         with Section XXXXXX, Operation and Maintenance Data.
B.     Provide one set of special tools required to maintain or dismantle equipment.
C.     Delivery: In accordance with Section XXXXX, Common Product Requirements.

PART 2          PRODUCTS

2.01       GENERAL

A.     Each piece of equipment specified shall be designed for continuous operation, 24 hours per day, 7
         days per week.

B.     Each piece of equipment specified shall be fabricated from Type 316L stainless steel having a bead
         blasted finish unless noted otherwise.

C.     Painting and coatings shall comply with Section XXXXX, Painting and Coating for Equipment
         Prepurchase.

2.02       MANUFACTURERS

A.     The design of the process for screening materials from raw sewage is based on the equipment from the
         first named manufacturer herein listed and as shown on the Contract Drawings.

B.     Materials, equipment, and accessories specified in this Section shall be products of:
1.      Huber Technology Inc., Model SSF-HF.
2.      Vulcan Industries.
3.      Johnson Screens.

2.03       SYSTEM DESCRIPTION

A.     This Section specifies mechanically cleaned stair type screens for collection and removal of solids and
         fibrous material from municipal wastewater.

B.     Manufacturer shall provide screens, motors, gear reducers, solenoid valves to control wash water flow,
         level elements and transmitters, controls, control panels, and lifting attachments, as a complete
         integrated package to ensure proper coordination, compatibility, and operation of the system.

C.     Mechanically Cleaned Screen
         1.      Each mechanically cleaned screen shall be a stair type screen with two sets of vertical plates, one
                  movable and one fixed. Each mechanically cleaned screen shall consist of a frame, gear reducer,
                  motor, mounting legs, fixed pivot point for lifting screens from channel, and all necessary
                  appurtenances to provide a complete mechanical screening system.
         2.      The screen shall be cleaned by the rotating motion of a movable set of step-shaped vertical
                  plates. As the plates rotate, they shall lift trapped waste materials to the next stair of a fixed set of        
                  vertical plates. The moving action shall not result in an appreciable quantity of screened
                  material falling or rolling off of the screen back into the influent wastewater.
         3.      At the top stair of each screen, the waste materials shall discharge into a discharge chute without    
                  the use of brushes or spray washers. The discharge chute shall direct the screenings into a sluice    
                  trough (provided by others).
         4.      The screen assembly shall be designed with a pivot and lifting arrangement that will allow the  
                  screen to be rotated out of the channel for maintenance access. No disassembly or any other
                  operation shall be required when lifting the screen. All other screens and the sluice trough    
                  (provided by others) must remain operational while an individual screen is completely or partially
                  pivoted out of its channel.

2.04       OPERATING CRITERIA

A.     Equipment furnished under this Section shall be suitable for operation in municipal wastewater. The
         wastewater will contain fine and fibrous material including but not limited to hair, plant material, sand,
         silt, petroleum products, industrial solvents, animal fats, oils and plastic bags.

B.     Equipment will be exposed to variable concentrations of hydrogen sulfide.

C.     Each screen shall be designed for continuous operation, and shall be suitable for operation under the
         following conditions:

1.      Number of Units: Two.
2.      Exposure: Indoors.
3.      Peak Hourly Flow (per screen): 55.2 mgd.
4.      Average Daily Flow (per screen): 24 mgd.
5.      Minimum Flow (per screen): 2.9 mgd.
6.      Wastewater Temperature Range: 40 to 80 degrees F.
7.      Wastewater pH Range: 6.3 to 7.5.
8.      Channel Width: 5 or 6 feet.
9.      Channel Depth: 9.0 feet.
10.    Maximum Upstream Water Depth (feet), 40 Percent Binding/55.2 mgd per Screen: 5.5 feet.
11.    Minimum Downstream Water Depth at 2.9 mgd/Screen: 1.0 feet.
12.    Channel Invert Elevation (at screen): 4967.00.
13.    Channel Invert Elevation (upstream of screen): As recommended by manufacturer.
14.    Operating Floor Level: 4976.00.
15.    Screen Frame Angle from Horizontal: 45.
16.    Open Space Between Screening Blades:  6 mm.
17.    Screening Plate Width: 3 mm.
18.    Minimum Height of Screenings Discharge from Floor: 3 feet 0 inches.
19.    Minimum Slope of Sluice Trough: 2 percent.
20.    Maximum Height of Screening Handling Equipment: 14 feet.

2.05       MATERIALS

A.     Unless otherwise specified herein the equipment shall be manufactured from AISI Type 316L stainless
         steel shapes, pipes, and sheets. All mechanical parts shall be designed to handle the forces that may be
         exerted on the unit during fabrication, shipping, erection, and proper operation.

B.     The equipment, after its fabrication, shall undergo a passivation (pickling) process to ensure maximum
         resistance to corrosion. All stainless steel components and structures shall be submersed in a chemical
         bath of nitric acid and hydrofluoric acid to remove any residues that may be present on the material as
         a result of forming, manufacture, or handling. After removal from the pickling bath, the equipment must
         be washed with a high-pressure wash of cold water to remove any remaining surface debris and
         promote the formation of an oxidized passive layer, which is critical to the long life of the stainless steel.
         Submergence insures complete coverage. Spray on chemical treatments and glass bead blasting are
         specifically not acceptable due to their inability to provide complete and uniform corrosion protection.

2.06       FINE SCREEN EQUIPMENT

A.     General:
1.      Lubrication points for gears and motors shall be located outside of the enclosure when possible and
         shall be accessible from the operating floor level. There shall be no parts requiring lubrication located
         under water. Oil lubricated gear reducers shall be provided with sight tubes to indicate oil levels.
2.      The screen support shall have a fixed pivot mount allowing it to be lifted out of the wastewater to a
         horizontal position where it is easily accessible from the operating level. Pivoting the screen shall not
         require disassembling the screen, or disassembling or moving the sluice trough.
3.      Each screen is to be a totally enclosed structure. Each screen enclosure shall be provided with a 4-inch
         stub flange for connection to the odor control system. The stub flange shall not be located on one of
         the removable panels.

B.     Welding: All welding shall conform to AWS-D1. Weld splatter shall be prevented by the use of
         splatter-prevention paste at welded joints. Weld slag shall be removed.

1.      After welding operations, stainless steel components shall be cleaned of organic contamination using a
         solvent that is free of chlorides. After organic materials have been removed, embedded iron shall be
         removed from the stainless steel by pickling with nitric or hydrofluoric acid.
2.      Welded ferrous or steel components shall be provided with continuous weld between full penetration
         skip welds or sealed with a paintable silicone caulk.

C.     Frame of Screen:

1.      Frame shall be fabricated from 0.2-inch (5-mm) thick AISI Type 316L stainless steel. The frame shall
         accommodate fixed step blade packages, blade cross pieces, slewing bracket unit, eccentrics, and
         drive unit including gear, shaft, and motor.
2.      Frame shall be accurately set into position in the channel and shall be capable of supporting the entire
         screening assembly when suspended from the pivot shaft attached to the support legs. The screen shall
         be installed with an angle of 45 degrees from the horizontal. If the total screen width is less than the
         specified channel width, the opening shall be sealed to prevent flow from passing around the screen.
3.      Frame sides shall be fully welded to a 0.2-inch (5-mm) thick baseplate, stationary 0.16-inch (4-mm)
         thick step blade cross member brackets and a 0.2-inch (5-mm) thick drive console. The drive console  
         shall be designed to accommodate eight adjusting bolts. Four adjustment bolts shall be parallel to the
         screen angle and four shall be perpendicular to the screen angle. The parallel bolts shall adjust the
         horizontal position of the moveable step blades. The perpendicular bolts shall adjust the vertical
         position of the moveable step blades.
4.      The frame sides shall form the supports for cover panels at the sides, the front, and the back of the
         screen.

D.     Step Screen Blades:

1.      Moveable step blades shall be cut from 1/12-inch (2-mm) thick cold- rolled stainless steel sheets. The
         front-face of the step blade shall have a curved, hook-like shape thus preventing screenings from
         rolling or falling down from the steps. The steps shall have a horizontal length of 2 inch (50 mm) and a
         vertical height of 4-1/8 inches (105 mm) from step to step. The rear-face of the moveable step blade
         shall have a series of saw-tooth patterns cut into the straight edge of the step blade to slice through any
         debris that may accumulate on the cross member supports for the stationary step blades. Each saw-
         tooth pattern shall consist of ten angular cuts in succession, resulting in a 7-7/8-inch (200-mm) long
         serrated edge along the rear-face of the step blade. Each cut shall consist of a 13/16-inch (20-mm)
         straight length angled 14 degrees off the rear step blade straight edge followed by a 1/5-inch (5-mm)
         cut perpendicular to the straight edge. The moveable step blades shall be mounted in a series of cross
         member brackets anchored to the moveable side plate.
2.      Stationary step blades shall be manufactured from 1/12-inch (2-mm) thick cold-rolled stainless steel
         sheets. The stationary step blades shall have exactly the same step shape as those of the moveable step
         blades. The stationary step blades shall be mounted in a series of cross member brackets anchored to
         the step screen frame.
3.      The effective screening area of the step screen shall be produced by alternating stationary step blades
         with moveable step blades and spacing the step blades 1/4-inch (6-mm) apart. The open space
         between the lamina is maintained by 3-inch long HDPE spacer inserts mounted along the length of the
         moveable step blades at a distance not less than 2 feet apart. The resulting effective screening area  
         shall have a minimum of 75 percent free open-area.
4.      The movable step blades lift the screenings to the next higher stationary step with each rotation cycle of
         the gear motor. The number of rotation cycles performed in each operating cycle is dependent upon
         the hydraulic conditions in the channel. After completion of an operating cycle, the step blades shall
         come to rest in the home position such that the horizontal surface of the step blades are aligned across
         the width of the channel. A proximity sensor shall send a signal to the PLC when the moveable step
         blades are in their home position causing the gear motor to stop and hold the step blades in alignment.
5.      The screen shall utilize two sets of step blades consisting of upper and lower packages. The upper
         blade package shall consist of 2-mm thick moveable stainless steel blades and 6-mm thick fixed
         polypropylene blades to prevent debris falling into the channel prior to discharge unless all stainless
         steel upper lamina are required. The resulting tolerance between the plastic jacket and the adjacent
         stationary step blade shall be 0.04 inch (1 mm).

E.      Bottom Flushing Pipe: A 1-1/4-inch diameter stainless steel flushing pipe shall be mounted parallel to
         the back of the faceplate along the width of the channel to prevent heavy material from depositing
         below the step blades. The flushing pipe shall have 1/2-inch diameter perforations every 8 inches. The
         flushing pipe will be fed with nonpotable plant effluent through a stainless steel pipe. The flushing pipe
         shall be fitted with a solenoid valve controlling the feedwater to the flushing pipe. Solenoid valve must
         meet Class I, Division 2 requirements. Screens with effective screening areas greater than 4 feet 4
         inches shall be equipped with dual flushing pipes and dual feedwater connections.

F.      Home Position Sensor:

1.      Home-position proximity sensor shall send a signal to the plant control system that shall cause the gear
         motor to stop the rotation of the moveable step blade package, when it is aligned with the stationary
         step blade package. The signal shall be generated when the metal flag attached to the eccentrically
         rotated block passes the frame mounted sensor.
2.      Mounting mechanism of the sensor shall be adjustable to enable the moveable step screen package to
         be stopped in the proper location.
3.      The proximity sensor shall be an inductive proximity sensor. The sensing distance of this sensor shall be
         5/64 inch (2 mm).

G.     Gear Motor Drive Mechanism:

1.      The drive unit shall be a gear motor rated for continuous duty and shall be selected to match the
         requirements of the particular screen. The drive motor shall be a 5-horsepower unit designed for
         application in a Class I, Division 2 area. The motor shall be a constant speed unit rotating at
         1,680 rpm, and shall be powered by 230/460V ac, 60-Hz, three-phase power. The motor shall be
         compatible with an adjustable drive system to be supplied by others. Provide motors in accordance
         with Section XXXX, Low-Voltage AC Induction Motors, and Induction Motor Data Sheet located
         in Supplements following End of Section.
2.      The drive unit shall be direct coupled to the screen drive shaft through the gear box. The gear box
         housing shall be constructed from ASTM A48, Class 30 cast iron. The drive unit shall be sealed from
         the screenings transport area with a stainless steelplate, which is welded to the frame and forms the
         drive console.
3.      The screen shall be equipped with electronic overload protection by one true-power monitors to stop
         the screen and initiate an alarm in the event of overload. The true-power monitor shall monitor both the
         upstroke and the down-stroke of the screen. Shear pins for overload protection are not acceptable.

H.     Covers:

1.      The step screen shall include AISI Type 316L stainless steel covers for odor control and general plant
         safety. The covers shall extend from the deck level to the top of the screen. The covers on the front of    
         the screen shall be easily removable. The covers on the sides and the back of the screen shall be
         fastened in place by screws.
2.      Each screen cover shall be provided with a 4-inch stub flange for connection to the odor control
         system. The stub flange shall not be located on one of the removable panels.

2.07       ELECTRICAL

A.     General:
1.      All electrical components and assemblies shall bear a UL 913 label. All electrical work shall conform
         to the requirements of this and other referenced sections of these Specifications.
2.      All electrical components at the screen or within the screen housing shall be rated for Class I, Division
         2, Group D Hazardous Environment as defined by the NEC.

2.08       ADJUSTABLE FREQUENCY DRIVE

A.     Each screen motor shall be compatible for use with a UL certified AFD (Adjustable Frequency Drive).
        AFDs shall be provided by others.

B.     The AFD shall operate at half speed for normal operation of the screen and full speed during high
         screening loading conditions.

2.09       INSTRUMENTATION AND CONTROLS

1.      In accordance with general control requirements specified in Section 40 99 90, Package Control
         Systems.
2.      Each Fine Screen shall be supplied with local control panel, as defined below:

 Fine Screen 1 Local Control Panel:
310LCS35001
NEMA 4X
316 Stainless steel

Fine Screen 2 Local Control Panel:
310LCS35002
NEMA 4X
316 Stainless steel

3.      Each Local Control Panel shall be provided with the following:
         a.      Fine Screen LOCAL/REMOTE selector switch
         b.      Fine Screen EMERGENCY STOP pushbutton

4.      Fine Screen System remote control and alarm monitoring provided by plant control system, furnished
         by others.

5.      UL Listing Mark for Enclosures: Mark station “Listed Enclosed Industrial Control Panel” per UL
         508A.

2.10       FINISHES

A.     For nonstainless steel and nonaluminum metal surfaces, prepare, and prime, and finish cost in
         accordance with Section XXXXXX, Painting and Coating for Equipment Prepurchase.

B.     Stainless steel shall be cleaned and passivated following fabrication in accordance with ASTM A380.

2.11       SOURCE QUALITY CONTROL

A.     Factory Tests and Adjustments:

1.      The screens shall be factory assembled and factory tested at the point of manufacture. Test each screen assembly, in its operating position, to ensure proper operation of plates, controls, protective devices, and override controls.

2.      Run equipment and test for minimum 6 hours. Testing shall be done in factory with unit oriented in its installed position.

PART 3          EXECUTION

3.01       PRODUCT DELIVERY, STORAGE, AND HANDLING

A.     As specified in Section XXXXX, Common Product Requirements.

3.02       INSTALLATION

A.     In accordance with manufacturer’s written instructions.

B.     Anchor Bolts: Accurately place using templates provided by manufacturer, and as specified in Section
        XXXXX, Metal Fabrications.

3.03       FIELD FINISHING

A.     Touchup damaged areas of painted ferrous metal in accordance with and as specified in Section
         XXXX, Painting and Coating for Equipment Prepurchase.

3.04       FIELD QUALITY CONTROL

A.     Perform in accordance with Section Engineer, Equipment Testing and Facility Startup.

B.     Functional Test:

1.      Conduct on each unit with potable water (or other suitable water).
2.      Test shall include 6 hours of continuous operation of each piece of equipment specified herein.
3.      Confirm coordination of operation with sluice trough, diverter gates, and washer/compactors.
4.      Head Loss at Operating Condition: The Subcontractor shall demonstrate a head loss less than the
         maximum while passing the design flow.
5.      Any noticeable damage to the equipment shall be considered a failure.
6.      Supply required metering devices and gauges necessary to demonstrate system performance. Supply
         and install gauge connections as required.

C.     Performance Test:

1.      Conduct on each unit.
2.      Test system during process commissioning with specified service fluid.
3.      Test shall include 6 hours continuous operation of each piece of equipment specified herein.
4.      Successful functional tests done with water shall not constitute acceptance of screening system. System
         will only be accepted after successful performance tests on specified fluid at stated Operating Criteria.
5.      The step screen shall operate automatically based on the water level differential.
6.      Proposed test procedures shall be developed by the Manufacturer and submitted to Engineer for
         review, comment and approval. Testing shall not begin until the test procedures have been approved
         by Engineer.
7.      A qualified representative of the manufacturer shall supervise each test, analyze data, and certify the
         equipment’s performance during the test.
8.      In the event that the equipment does not meet the requirements of the specifications during the
         performance test, the representative of the manufacturer shall make such changes in the equipment and
         methods of operation as deemed necessary and as approved by Engineer and pay for all reasonable
         costs to re-test, including those of Engineer and Owner. The necessary adjustments shall be made as
         soon as practical, but within a period not to exceed 30 days. Following the adjustments, make a
         second test regime similar to the first testing regime. In the event that the equipment still does not
         achieve specified performance during the second test, then the equipment will be subject to rejection.
9.      If, after a maximum of two test runs, in the opinion of EngineerL, the equipment meets the performance
         requirements specified herein, Engineer will recommend the acceptance of the equipment. If, in the
         opinion of Engineer, the performance test results do not meet the requirements specified herein,
         Engineer will notify the manufacturer and the Owner of the non acceptable performance Any failure of
         the performance requirements shall be deemed defective Work under the Purchase Order executed
         between Engineer and Manufacturer.

3.05       MANUFACTURER’S SERVICES

A.     Manufacturer’s Representative: Present at Site or classroom designated by Owner, for minimum
         person-days listed below, travel time excluded:

1.      One trip for 3 person-days for installation assistance and inspection.
2.      One trip for 3 person-days for functional testing, completion of Manufacturer’s Certificate of Proper
         Installation, and training. Training shall not commence until an accepted detailed lesson plan for each
         training activity has been reviewed by Owner and Engineer.
3.      One trip for 3 person-days for facility startup.
4.      A credit shall be applied to Engineer for any unused manufacturer Field Services.

B.     See Section XXXX3, Manufacturers’ Field Services, and Section XXXXX, Equipment Testing and
         Facility Startup.

Mechanical Screening Equipment

PART 1 -  GENERAL

1.01          SUMMARY
A.    This Section includes all labor, materials, equipment, and incidentals required for delivery to the project site ready for installation (1) rotating perforated plate screen and one (1) inclined shaftless screw conveyor for removing floating particles and fibrous material and for conveying, washing, dewatering and compacting the screenings before discharging the material into a dumpster; as shown on the drawings and described in the following specification. The treatment objective for the rotary drum screen is to capture solids from raw wastewater, wash them to remove organic solids, then compact and transport them to the dumpster.
B.    The rotary drum screen and conveyor shall be located in the new Headworks Room.
C.    The rotary drum screen unit and conveyor shall consist of an internally feed perforated plate screen basket, cleaning brushes, integral screenings and screenings wash-press, pivot stand,
bagger, inclined shaftless conveyor, and controls.
D.    Related Work Specified Elsewhere:
1.     General Requirements: DIVISION 1
2.     Manufacturer's Field Services: DIVISION 1
3.     Steel: DIVISION 5.
4.     Painting: DIVISION 9.
5.     Instrumentation & Electrical: DIVISION 16.

1.02          REFERENCES
A.    Applicable Standards
1.     American Bearing Manufacturers Association (ABMA).
2.     American Gear Manufacturers Association (AGMA).
3.     American Iron and Steel Institute (AISI).
4.     American National Standards Institute (ANSI).
5.     American Society for Testing and Materials (ASTM):
a.     A36 - Structural Steel.
b.     A48/A126 - Gray Iron Castings.
c.     A322: Carbon and Alloy Steel Bar.
6.     American Welding Society (AWS).
7.     National Electrical Code (NEC).
8.     National Electrical Manufacturers Association (NEMA).
9.     National Fire Protection Association (NFPA).
10.   Occupational Safety and Health Act (OSHA).
11.   Underwriter’s Laboratories (UL).

1.03          QUALITY ASSURANCE
A.    Like items of equipment provided hereunder shall be the end products of one Manufacturer in order to achieve standardization for appearance, operation, maintenance, spare parts, and manufacturer's service.
B.    This Manufacturer shall have the responsibility of providing the equipment, accessories, installation supervision, and testing services required to provide a functioning system.
C.    Products used in the Work of this Section shall be produced by the Manufacturer regularly engaged in the design and production of screening equipment for a minimum of ten (10) years
and with a history of successful installations in North America.

D.    Manufacturer shall have a screen tested with panels of same size perforations and range of flows per plate surface area. Testing and report shall be conducted by an authority independent of the manufacturer. Test results shall include headloss and solids screen capture quantities and ratio with total solids contained in wastewater.
E.     All equipment shall be designed, fabricated and assembled in accordance with the best engineering and shop practices. Individual parts shall be manufactured to standard sizes and gages, so that repair parts, furnished at any time, can be installed in the field. The equipment shall be new, not have been in service at any time prior to delivery, except as required by tests.
F.     Manufacturer shall have a satisfactory field service record to be verifiable by Engineer in communication with no less than four (4) references for current users of similar equipment
furnished.

1.04          SUBMITTALS
A.    Submit as specified in DIVISION 1.
B.    Includes, but is not limited to the following:
1.     Complete manufacturer’s data, specifications, and detailed drawings for all equipment and materials which shall include complete descriptive data to define materials sizes, capacities, types, models, accessories, etc. Drawings and other information shall be suitable for erection and installation of equipment and materials.
2.     Test report from independent authority described in Quality Assurance.
3.     Recommended spare parts list.
4.     Electric power requirements, wiring diagrams, and schematics for all electrical equipment and devices.
5.     Refer to Section 16901 – Control Panels for additional submittal requirements.
6.     All structural loads imparted to the structure.
7.     Submit screen headloss calculations at peak and design flows. The calculations shall include clean screen 0 percent and 70 percent of screen plate area blinded.
8.     Manufacturer’s surface preparation, shop priming, and machined metal surface rust inhibitive compound requirements.
9.     Recommended unloading method at project site including implement (e.g., forklift, etc.)
and maximum container or package weight.
10.   List of installations, as described in Quality Assurance, including current Owner representative name, address, telephone number and fax number.
11.   Installation, operation, and maintenance instruction manuals prior to delivery of equipment
and materials.
12.   Submit structural calculations for the conveyor supports stamped by an Engineer certified to practice in the State of Colorado.
13.   Parts lists.
14.   Power and control schematic diagrams indicating factory and field wiring.
15.   Conveyor name plate data.
a.     Plant serial number
b.     Fabricator
c.     Capacity (under normal conditions)
d.     Empty weight
16.   Conveyor capacities under specified conditions.
17.   Certification of 225 Brinell spiral by an independent testing laboratory.
18.   Operation & Maintenance manual.
19.   Manufacturer’s product warranty.
20.   Motor data consisting of the following.

a.     Manufacturer's name and serial number.
b.     Horsepower output.
c.     Temperature rise and method indicated.
d.     Maximum ambient temperature.
e.     Insulation class.
f.      Rpm at rated load.
g.     Frequency.
h.     Number of phases.
i.      Voltage.
j.      Rated load amperes.
k.     Locked rotor amperes or code letter.
l.      Service factor.
m.    Maximum noise level of pump/motor unit (dBA).
n.     Efficiency, determined in accordance with IEEE Standard 112, Method B.
o.     Dimensions for enclosure and shafts.
p.     Weight.
q.     Bearing information.
r.      Structural design calculations certified by Colorado registered professional engineer.

1.05          WARRANTY
A.    The manufacturer shall warrant that all Equipment shall be free of defects caused by faulty material or workmanship and shall replace those parts for at least a period of two (2) years from the date of start-up.
B.    Multiple warranties for individual components shall not be acceptable.

1.06          DELIVERY, STORAGE, AND HANDLING
A.    Deliver, store and handle all equipment and materials in a manner to ensure installation in sound and undamaged condition, to prevent damage from exposure to the elements, and in accordance with the requirements in DIVISION 1.
B.    Adequately seal and protect equipment for outdoor storage at project site. Protect all bearings with grease packing or lubrication oil.

PART 2 -  PRODUCTS

2.01          ACCEPTABLE MANUFACTURERS
A.    Huber Technology, Inc.
B.    Lakeside Equipment
C.    Johnson Screens
D.    Engineer approved equal.

2.02          SERVICE CONDITIONS:
A.    The screening system shall be used to screen raw domestic wastewater gravity fed to the
Headworks Building from the collection system.
B.    Screenings captured and collected from the screen are to be washed, dewatered and compacted.
Processed screenings shall be conveyed and deposited into a disposal container/roll-off dumpster supplied by others.

2.03          GENERAL REQUIREMENTS
A.    Provide ready for installation for the following:

1.     One (1) perforated plate rotary drum screen with integral washer/dewater/compactor unit.
2.     One (1) screenings transfer chute as indicated on drawings.
3.     One (1) inclined shaftless screw conveyor as indicated on drawings.

B.    Include with each screening unit:
1.     Screen, wash press, transfer chute, inclined shaftless screw conveyor, motors, gear reducers, controls, control panels, and lifting attachments
2.     All items necessary for complete assembly.
3.     All appurtenances and safety devices required for proper operation.
4.     All manuals, drawings, parts list, and special tools required for assembly, maintenance, and operation.
5.     Lubricants (if required) for start-up procedure specified.
6.     Standard set of spare parts.

C.    The screening equipment shall be delivered completely assembled or in convenient sections as permitted by common carrier and required for installation.

D.    All Equipment shall be designed and built for 24-hour intermittent or continuous service and for moderate shock without overheating, excessive vibration or strain.

E.     All bolts, nuts and washers shall be 304 stainless steel.

2.04          OPERATING CONDITIONS
A.    General
1.     Wastewater enters the inside of the drum screen and solids within the incoming flow shall progressively collect onto the fixed screening element. The collected solids captured on the screen gradually blind the submerged media which causes the upstream water level to rise. At a predetermined differential water level (between the upstream
and downstream of the screen) programmed into the PLC; the drum and conveyance spiral drive will operate.  Design motors shall be activated to: (1) rotate a section of clean drum screen into the wastewater, (2) clean the drum screen and (3) transport, wash, compact, and convey the screenings to the transfer chute (4) convey dewatered screenings to a dumpster located in the upper headworks room.
B.    Design Requirements:
1.     Design Flows:
a.     Peak plant flow: 6.3 MGD
b.     Design plant flow: 3.0 MGD
2.     Influent TSS: 164 mg/L
3.     Rotary Drum Screen with Integral Screenings Washer/Dewater/Compactor:
a.     Number of units: One (1)
b.     Maximum effective size of screen panel perforations: 1/4 inch (6 mm)
c.     Maximum Drum Motor Hp: 2 Hp
4.     Transfer Chute from Screen Discharge to Conveyor:
a.     Number of units: One (1)
b.     Minimum Angle of Inclination: 60 Degrees
5.     Inclined Shaftless Screw Conveyor:
a.     Number of units: One (1)
b.     Maximum Conveyor Design Loading Rate: 600 lb dry solids/hr. c.     Conveyor Trough Load: 25%.
d.     Cake Density: 50-70 lbs/ft3.
e.     Maximum Spiral Speed: 25 RPM.
f.      The conveyors shall be designed to start and operate with the trough 100% full of dewatered screenings without damage or overloading of any component.
g.     Minimum Screw Diameter: 10.0 inches
h.     Angle of Inclination: 43 Degrees
i.      Maximum Motor Hp: 5 Hp
j.      Components shall be designed to handle abrasive solids with minimum wear.
k.     Conveyor shall be designed to start when the conveyor trough is fully loaded.
l.      Conveyor and supports shall be designed and stamped by Colorado Registered
Professional Engineer by the Manufacturer for the unsupported lengths indicated on the Drawings.
6.     Location Rating:
a.     Class 1, Division 1

C.    Dimensions and Elevations:
1.     The following shall be as recommended by the manufacturer to meet operating performance requirements. Dimensions are expected to be within the following values:
a.     Screen installation angle: 35 degrees
b.     Influent channel bottom elevation: 4860.00
c.     Influent channel top elevation: 4865.00
d.     Influent channel width: 3’0”
e.     Influent channel recess width: 4’9”
f.      Water level downstream at peak flow: 1’6”.
g.     Max water level upstream: 2’6”
h.     Upper headworks operating floor elevation: 4878.00
2.     The drawings show dimensions, shape and elevations proposed by one manufacturer. The
Contractor is responsible for executing any revisions to meet the recommendation of the manufacturer providing the equipment at no additional cost to the Owner.

2.05          MECHANICAL SCREEN
A.    Unless otherwise specified all equipment to be manufactured from 304 stainless steel. The equipment, after its fabrication, shall undergo a passivation (pickling) process to ensure maximum resistance to corrosion.

B.    Screen
1.     The cylindrical fine screen shall be designed and built to withstand all static and hydraulic forces exerted by the liquid to the screen. All structural and functional parts shall be sized for the loads encountered during screening, conveying and pressing operations.
2.     The screen basket shall be of cylindrical shape.
3.     The perforated plates shall be around the entire basket circumference.
4.     Bar type screens will not be acceptable.
5.     The screen shall be designed to handle the maximum flow with the maximum upstream and downstream water levels indicated in Section 2.04C.
6.     Seal plate shall be provided between the circular screen and the channel and shall conform
to the following:
a.     One-piece fabricated stainless steel
b.     Sufficient height to prevent bypassing of flow around screen at the maximum screen hydraulic capacity.
c.     Brush shall to be clamped to the seal plate to seal the gap between the fixed seal plate
and the rotating screen basket.
7.     Stainless steel support stand shall be provided to allow easy removal of the screen basket from the channel for maintenance.
8.     The screen shall be provided with a stainless steel housing of four wall plates and a cover.
The cover shall be removable and shall be secured with turn-locks.

C.    Cleaning Brushes
1.     The screen basket shall rotate in one direction and pass through the topmost position where
it is cleaned with spray nozzles and a brush penetrating the depth of the screen to ensure positive screenings removal.
2.     The brush shall be designed to ensure cleaning of the spaces to the full depth of the perforated plate. The cleaning brush shall be mounted upon a stainless steel holding device which keeps the brush in constant contact with the basket.
3.     The mounting device shall allow for adjustment for brush wear.

D.    Screenings Conveyor and Screenings Wash-Press
1.     An auger screw that is entirely made of stainless steel shall be provided to transport and dewater the screened material.
2.     The screenings conveyance and screenings wash-press shall be sized according to the flows
listed in paragraph 2.04 B.
3.     A compaction zone shall be an integral part of the screenings screw conveyer and transport tube design. The compaction zone shall be designed to form a screenings plug of material
and to return water released from the screened material back to the wastewater channel.
4.     The screenings shall be discharge to an enclosed transfer chute that transfers the compacted screenings to the inclined screenings conveyor. This chute will be totally enclosed from the
screenings discharge to the inclined conveyor.

E.     Drive
1.     Drive unit shall be the manufacturer’s standard design.
2.     All motors shall be UL listed for Class 1 Division 1 Groups D locations.
3.     All motors shall meet the requirements of Section 16150.

F.     Spray Wash System
1.     An automatic spray wash system shall be provided for cleaning of the screen basket and shall be operated only while the screen basket is rotating.
2.     Shall be of manufacturer’s standard design.
3.     The manufacturer shall provide any solenoid or other valves required for the automatic operation of the spray wash system.
4.     Any solenoid valves shall be operated by the programmable logic controller. Individual manual operation of each solenoid shall also be possible from the control panel.
5.     If the design of the spray wash system requires the use of a Y-strainer for the incoming plant water supply, one will be provided by the manufacturer.

G.    Anchor Bolts
1.     Equipment manufacturer shall furnish all anchor bolts of ample size and strength required to securely anchor each item of equipment. Anchor bolts, hex nuts, and washers shall be
304 stainless steel.
2.     Anchor bolts shall be set by the contractor. Equipment shall be placed on the foundations, leveled, shimmed, bolted down, and grouted with a non-shrinking grout.
3.     Anchor bolts shall conform to Section 03151 – Concrete Anchors.

2.06          SCREENINGS CONVEYOR
A.    Construct conveyors from type 304 stainless steel. Minimum material thicknesses and dimensions are as follows. Manufacturer shall provide thicknesses required for specific installation:
1.     Trough Body and Chutes: 3/16" plate
2.     Trough Top Flanges: 3/16" angle or formed as part of trough body
3.     Trough Covers: 1/8" plate
4.     End Plates: 3/8" plate
5.     Coupling Guards: 1/16"
6.     Internal Stiffeners: 3/16"
7.     Supports:
a.     Welded to Trough Body: 3/8" b.     Saddle-Type: 3/16"
8.     Bolts/Nuts/Washers: ANSI M12 or larger, type 304 stainless, Grade 8.8, hex-head, flat-face
washers.
9.     Gaskets; 1/8-inch neoprene, 50 durometer.
10.   Wear Liner: 1/2-inch polyethylene (UHMW).
11.   Spiral Flighting High Strength Alloy Carbon Steel:
a.     Minimum 225 Brinnell.
b.     1.0 inches minimum thickness x 3-inches wide.

B.    Trough, Covers, and End Plates:
1.     Conveyor trough bodies to be rolled to shape, with flanges welded to the trough. Conveyor
troughs shall be provided with inlet and discharge chutes as required and as indicated on the Drawings. Glue 1/8-inch thick neoprene gasket over full face of one flange for adjoining flanges.
2.     Fabricate end plates from single steel plates and weld or bolt across ends of the trough.
Fabricate drive motor/gear reducer/bearing/stuffing box assembly, end shaft/end bearing/stuffing box assembly of all welded construction using steel plate, shaped to
support end bearings and drives in true alignment. These assemblies to be bolted to the
trough end plate using a matching mounting plate.
3.     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. Include separate support points under the drive end assembly and end shaft assembly welded as an integral part of these assemblies.
4.     The inclined screw conveyor shall be provided with a 2-inch diameter drain flange as indicated on the Drawings for drainage of excess liquid in conveyor during cleaning
activities.
5.     Stiffeners shall be placed across the top of the trough and fastened to both sides of the trough to maintain the shape and act as a face seal for the covers.
6.     Trough Covers: The entire trough shall be covered by a stainless steel plate, hinged on one side and clamped on the other. The covers shall be approximately 4-feet in length to allow easy access to the conveyors. The length of the covers will be such that each edge joint
rests upon a trough stiffener. A neoprene gasket shall be installed along the trough sides and stiffeners to ensure a drip-proof connection. All gasket material shall be shielded by
the covers.
7.     The inlet to each trough shall be equipped with reinforced flange.
8.     The troughs of the screw conveyors shall be provided with a 2-inch NPT connection for flushing and to lubricate the liners to prevent excessive wear.

C.    Spiral Flighting (Shaftless):
1.     Screw conveyor spirals shall be cold-rolled spirals made of superior, high-strength spring carbon steel bars of not less than:
a.     225 Brinnell hardness.
b.     80,000 psi yield strength, minimum.
c.     1-inch thickness for spiral diameters 10-inches and greater.
2.     Spiral flights shall be designed to prevent distortion and jumping in the trough. The torsional rating of the auger flighting shall not exceed 35 percent of the yield value in the extreme fiber of the flight material.
3.     Spirals shall be formed in a spiral-forming machine to the diameter and pitch required.
Each formed sub-section of a spiral shall be factory-welded into full lengths. Sectional spirals made from abrasion resistant (AR) plate or AR bar are not acceptable.
4.     Maximum spiral neck down from outer edge to inner edge shall be 20 percent. Spiral shall have no grind marks on outer edge.
5.     Manufacturer shall demonstrate that, at 250 percent of the motor nameplate horsepower,
the drive unit cannot produce more torque than the torsional rating of the flighting, and that the spring effect of the spiral shall not exceed +0.04 inch per foot of length at maximum load conditions.
6.     The spiral’s outside face shall be flat and smooth, with the face parallel to the axis of the screw conveyor, and the edges of the outside face rounded so as not to have a sharp edge.
7.     The connection of the spiral to the drive system shall be through a flanged connection plate that is welded to the spiral forming a smooth and continuous transformation from the flange
plate to the spiral. The drive shaft shall have a mating matching flange and shall be bolted to the spiral connection plate. The drive shaft shall be shaft-mounted into the gear reducer output shaft.
8.     The tail (end opposite the drive end) shall not be restrained in any manner (i.e., no tail bearings, thrust plate, etc.).
9.     A gland packing ring consisting of a minimum of two Teflon-coated packing rings, nominal 1/2-inch square packing, with packing adjustment, shall seal the drive shaft at its penetration through the trough end plate.
10.   Wear Liner: Conveyor trough shall be equipped with a wear liner along the entire length.
The wear liner shall be fabricated of ultra-high molecular weight virgin, non-recycled polyethylene. To provide ease of replacement, the wear liner shall be provided in 4-foot
sections. The liner shall be held in place with clips out of the path of expected wear.
Bolted liners are not acceptable.
11.   Stuffing boxes to be complete with Teflon-impregnated packing, packing ring adjustment to tighten packing onto shaft, and packing, ring housing bolted to screw conveyor trough end plate.
12.   Thrust-carrying bearings to be fixed location, with spherical roller bearing mounted on
drive shaft, complete with bearing recess shoulder.  Non-thrust bearings to be non-locating, free-floating assembly and may be mounted with a tapered bore, plus adapter ring, on a
plain diameter shaft, where no power is transmitted from the shaft to another shaft.
Mounting of pillow block bearings shall be to the drive or end shaft assembly, and all components upon which the bearings are mounted, and must conform to the requirements of the bearing manufacturer for the loading and design conditions of the service.
13.   Gear reducers to be parallel helical or bevel helical, 2-, 3-, or 4-stage gear reducers, for shaft mounting. Size gear reducers 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) to 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.
14.   Bearings shall be designed for the thrust loads from the fully loaded start-up condition and shall have a L10 life of 30,000 hours. The reducer shall be the standard air-cooled unit with
no auxiliary cooling.
15.   V-belt driven speed reducer or chain driven reducer not permitted.

D.    Conveyor Supports:
1.     Each conveyor shall be furnished complete with supports suitable for mounting as required by the Manufacturer’s design. The supports shall be shop fabricated from structural steel
shapes and plates. The supports shall be designed to facilitate the unsupported lengths indicated on the Drawings. See Drawings for support detail.
2.     All structural members shall be designed such that the ratio of the unbraced length to least radius of gyration (slenderness ratio) shall not exceed 120 for any compression member and shall not exceed 240 for any tension member. In addition, all structural members and
connections shall be designed so that the unit stresses will not exceed the American
Institute of Steel construction allowable stresses by more than 1/3 when subject to loading of twice the maximum design operating torque of the screw conveyor drive motors.
3.     All shop welding shall conform to the latest standards of the American Welding Society.

E.     Inspection Door:
1.     Provide one (1) inspection door on the conveyor.
2.     Conveyor inspection door shall be 3/16 inch minimum stainless steel. Provide piano-type hinges and handles.
3.     Inspection door shall be furnished with 304 stainless steel grid with 2 inch by 2 inch mesh
to prevent entry of foreign objects.
4.     Inspection door shall be equipped with a NEMA 4 limit switch that will shut down the conveyor when the door opens.

F.     Transfer Chute:
1.     Provide a transfer chute for the connection between screen and inclined screw conveyor.
Chute shall be fabricated of 3/16” thick 304 stainless steel.
2.     Size, shape, and location shall be determined by manufacturer to ensure proper operation and collection of dewatered screenings as it leaves the screen.

G.    Discharge Chute:
1.     Provide discharge chute for load out of dewatered screenings into a roll-off dumpster.
Discharge chute shall be fabricated of ¼” thick 304 stainless steel.

H.    Safety:
1.     The conveyor shall be equipped with all guards, shields, and covers required by OSHA
standards and normal safety practices.

2.07          CONTROLS
A.    All controls necessary for the fully automated operation of the screening and conveyance system shall be provided.

B.    The electrical control system shall provide an automatic control of the screening system via a
differential upstream and downstream water level using ultrasonic level sensors in combination with an adjustable timer. The ultrasonic water level sensors shall conform to Section 16902. The inclined conveyor shall be automatically controlled on an adjustable timer.

C.    The electrical control system shall provide a timer to control the inclined conveyor. D.    Screen Control Panel:
1.     The screen control panel shall be UL 508A listed and comply with NEC Article 409 for industrial control panels.
2.     The remote control panel located in the electrical room shall be rated NEMA 12.
3.     The control panel shall be supplied with a single 480-volt, 3-phase power source.
4.     The control panel shall include a 480V-120AC control power transformer with primary and secondary fused protection.
5.     The control panel shall contain all required components for complete control and monitoring of the screen, compactor, washwater solenoid valve, conveyor, level controls and associated equipment. As a minimum, the following components shall be installed in the panel:
a.     Door interlocked main disconnect.
b.     Motor starters for screen drive, grinder/compactor, cleaning brush, and conveyor.
c.     Conveyor starter to be combination full voltage reversing (FVR)
d.     Control power transformer.
e.     Allen Bradley ControlLogix PLC.
f.      Operator interface touch screen.
g.     Uninterruptible Power Supply (UPS).
h.     Required circuit breakers, control relays, power supplies, selector switches and indicating lights.
i.      Provide and install a conveyor motion sensor (zero speed detection) at a location to
give positive indication of rotation of the spiral, 115 VAC, two output 5A contacts, inductive or proximity type, solid-state design with adjustable start-up delay timer.
6.     Jam Protection for the Screen/Conveyor:
a.     Jam protection shall be provided for the screen/conveyor by a current transducer connected to the PLC.
b.     Provide current transducer with properly sized current transformers. Current transducer and current transformers shall be installed in the control panel.
c.     Device sensing range shall be selected based upon the equipment being protected.
7.     All devices shall be factory installed, wired and tested. Terminal blocks shall be provided and labeled as required for power, control and instrumentation.
8.     The following inputs shall be provided to the control panel for connection from the plant control system:
a.     Screen remote start/stop.
b.     Conveyor remote start/stop.
9.     The following dry contact outputs shall be provided from the control panel for connection to the plant control system:
a.     Screen in Remote.
b.     Screen Run Status.
c.     Screen Failure (Common alarm for all equipment associated with the rotary drum screen).
d.     Conveyor in Remote
e.     Conveyor in Run Status
f.      Conveyor Failure
10.   The following analog outputs (4-20mA) shall be provided from the panel for connection to
the plant control system:
a.     Screen Influent Level.
b.     Screen Effluent Level.
11.   As a minimum the following selector switches, pushbuttons and indicating lights shall be mounted on the door of the control panel:
a.     Local/Remote switch.
b.     Hand/Off/Auto switch.
c.     Reverse Jog pushbutton.
d.     Power On indicating light.
e.     Run Status indicating light.
f.      Equipment Failure indicating light.
12.   Additional status points and adjustment of set points and operating parameters shall be available via the operator touchscreen. As a minimum the following parameters and status points shall be viewable and/or adjustable via the operator touchscreen:
a.     Screen Head Differential.
b.     Screen Head Differential Set Point.
c.     Backup Timer Setting.
d.     Jam protection current set point.
e.     Run Time.
f.      Run Status indication for all equipment.
g.     Identify cause of equipment Failure.

E.     Screen/Conveyor Local Control Station and Junction Box:
1.     The panel shall be a NEMA type 7 enclosure and be installed near the equipment and be suitable for installation in a Class 1, Division 1, Group D area.
2.     The panel shall act as the single point of electrical connection to the screen/conveyor. All
electrical equipment shall be wired at the factory to the panel. All conduits and fittings installed between the panel and the electrical equipment shall be aluminum or stainless steel and suitable for installation in Class 1, Division 1, Group D area. Conduit and cable installation shall conform in all respects to the National Electric Code. Conduit seals shall be installed as required.
3.     Conduit openings in the panel shall be provided as indicated and required to facilitate installation of the conduit and cabling to the main control panel and skid mounted equipment.
4.     The panel shall contain all required components to implement the control functionality specified and to allow for the electrical connection of the skid mounted equipment to the
main control panel. As a minimum, the following components shall be installed in the panel:
a.     Required pushbuttons, selector switches and indicating lights.
b.     Terminal blocks.
5.     As a minimum the following selector switches and pushbuttons shall be mounted on the
door of the panel:
a.     Screen and conveyor Forward/Reverse Jog selector switch.
b.     Emergency Stop pushbutton.
c.     Hand/Off/Auto switch

2.08          SEQUENCE OF OPERATION
A.    Hand Operation
1.     The spiral motor and spray wash shall run continuously.

B.    Automatic Operation
1.     The level sensors shall start the unit. After the differential level has been lowered, the unit shall continue to run for the length of time set on the off delay timer, typically set at 30
seconds. The press zone spray wash shall typically operate whenever the spiral runs. A
repeat cycle timer (on time first) shall be included to regulate the spray wash run time, as required.

C.    Emergency Stop
1.     The unit can be deactivated at any time by pressing either the control panel mounted or unit mounted Emergency Stop push button.

D.    Fault Conditions
1.     Motor overload or high current shall stop the drive motor and illuminate the fault light.

2.09          SOURCE QUALITY CONTROL
A.    Each screen system and controller shall be factory tested to ensure satisfactory operation.

2.10          ACCESSORIES
A.    Provide all templates and special wrenches or tools necessary for proper installation and maintenance of Equipment.

PART 3 -  EXECUTION

3.01          PREPARATION
A.    Prepare surfaces in shop and finish all surfaces as specified in DIVISION 9.
B.    Store all Equipment as specified in DIVISION 1 and as required to prevent damage.
C.    Assemble and test drive units in factory.

3.02          INSTALLATION
A.    In accordance with manufacturer's instructions and as indicated.
B.    Install all electrical conduits, wires, tubing, instrumentation and other appurtenances as required for satisfactory operation.
C.    Prepare surface and paint or touch up all surfaces as specified in DIVISION 9.

3.03          FIELD QUALITY CONTROL AND ADJUSTMENTS
A.    Manufacturer's Field Services: Provide all services as specified in DIVISION 1 and as follows:
B.    The equipment suppliers shall furnish the services of a factory-trained representative on site for a
period of no less than 2 days (16 hours). The representative shall inspect, adjust, calibrate and
place into operation the system, then train Owner operating personnel. If additional services are required to produce a fully operational system, they shall be provided at no cost to the Owner.