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Wastewater Treatment equipment manufacturer including grit master grit washer, grit conveyor, helical skimmers, nonmetallic helical skimmers, non-metallic helical skimmers, gritmaster grit washer, rotary scum skimmers, dipping trough skimmers, flight monitoring system, DAF, Plate settlers, and Hydropneumatic systems for Water and Wastewater Treatment applications |
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• S P E C I F I C A T I O N S F O R M O T O R I Z E D L E V E R O P E R A T E D S C U M C O L L E C T O R • |
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Motorized Lever Operated Scum Collector PART 1 - GENERAL
1.01 DESCRIPTION
- Requirements specified in the General Conditions and Divisions ___________ form a part of this specification. The Contractor shall provide and install automatically actuated 12-inch diameter scum collector pipes at each final clarifier Nos. ________ as indicated on the Drawings and specified herein, including anchor bolts, and as necessary, appurtenances to form a complete, installed, operational scum collection system. The purpose of the scum collectors is to remove surface scum from the clarifiers for transfer to a point of treatment . All exposed equipment and controls shall be suitably designed for direct sunlight exposure at the plant.
1.02 SCOPE
- Provide all tools, equipment, materials and supplies and perform all labor required for the installation and initial operation of the scum collection equipment. All work involved in the fabrication, erection, assembly and placement of the pumps in proper operating condition shall be in full conformity with the Drawings, Specifications, Engineering Data, printed instruction and recommendations of the pump manufacturer.
- A. Work Included in this Section - Principal items include:
- Scum Collection Equipment
- Controls
- Submittals / Shop Drawings
- Installation
- Testing / Start - up
- B. Related work NOT included in this Section:
- Metals, Division__________
- Painting and Protective Coatings, Division ____________
- Sludge Collection Equipment, Section ______________
- Instrumentation, Division_______________
- Piping, Valves and Fittings, Division _______________
- Electrical, Division _______________
1.03 QUALITY
Quality provisions of Section __________ shall form a part of this section. All equipment furnished under this section shall be:
- Of a design and manufacture that has been used in similar applications
- Be demonstrated to the satisfaction of the Owner that the quality is equal to equipment made by those manufacturers specifically named herein.
The Scum collection Equipment shall be as manufactured / supplied by Polytech Systems, Inc. Little Rock, CA. or District approved equipment.
- 1.04 SUBMITTALS
- Shop Drawings showing fabrication and assembly, together with detailed specifications and data covering performance and materials of construction, power drive, assembly parts, devices and other accessories forming a part of the equipment furnished, shall be submitted in accordance with the requirements of General Conditions. Data and specifications for the equipment shall include, but not be limited to the following:
- Electric Motor Data, including Manufacturer, size, operating voltage, number of phases, locked rotor current in amps, full load current in amps, and motor speed in rpm.
- Anchor bolt placement measured from construction joints in the concrete structure, and anchor bolt details, including projections from concrete.
- Materials of construction including slotted pipe, shafts, bearings, seals, drive assembly, including speed reducer.
- Interconnecting piping, drive shaft and motor details.
- Furnish seismic calculations as required in Section __________
1.05 DELIVER, STORAGE AND HANDLING
- Comply with the requirements set forth in Section ________ of these specifications. Protect equipment from exposure to the elements and keep all items thoroughly dry at all times. Package all spare parts or spare part assemblies in separate, sturdy, waterproof containers clearly marked with the name of the part or assembly, and the name of the unit of which it is a component.
- Part 2 - PRODUCTS
2.01 FABRICATION AND MANUFACTURE
Each slotted pipe shall include, but not be limited to: a slotted pipe, end supports, seal, lever collar, lever arm drive assembly, adjustable limit control, and other appurtenances for a complete installation.
2.02 COMPONENT UNITS
- A. GENERAL - Provide a motor-driven scum collector assembly for _________ of the clarifiers. Each scum pipe assembly shall operate independently from one another.
- B. SCUM PIPE - Each scum pipe shall be fabricated from 1/4 inch minimum thickness, 316 stainless steel, 12 inch diameter. The scum pipes shall be 20 feet long. Each scum pipe shall be furnished complete with necessary wall mounted bearings, bearing shall be U.H.M.W., end anchorage plates, support bearings, pipe support brackets, necessary gaskets and seals, levers, and anchorage parts. Each scum pipe shall have an accurately cut open slot, forming a 60ö angle in the top of the pipe to receive the skimmings when the pipe is rotated. The edges of the slot shall be parallel to the longitudinal axis of the pipe, and 1-inch wide bands of the full pipe periphery shall be left in the pipe, at appropriate spacing, but not more than a total of 2'-6", to act a stiffeners. Each pipe, after fabrication, shall be free of any noticeable warpage or distortion. Each scum pipe shall be supported at each end in such a fashion that a slight vertical or horizontal misalignment shall not interfere with smooth operation of the trough. Each pipe shall be supported by, and revolve in U.H.M.W. bearing housed in a 316 stainless steel holder with seal attached to the tank wall.
C. SEAL - A suitable water-tight seal shall be provided for the open end of the pipe. The seal shall be so constructed that it shall remain effective even with slight misalignment of the pipe and collar. The shall not be affected by grease, mild acids, or alkalis. The seal shall be readily removable without removing the pipe from the supporting bearings and shall not bind or impede the smooth action of the revolving pipe.
D. CONNECTING LINKAGE - Provide an adjustable 316 stainless steel connecting linkage to connect the drive assembly to the secondary scum pipe.
- E. DRIVE ASSEMBLY - The secondary scum collector drive assembly shall incorporate a motor and output speed reducer which drives a cam-actuated limit switch device. The lever shall be directly connected to the cam-actuator and the scum trough. A connection for manual operation shall be provided on all assemblies.
- The output shaft of each reducer which operates the Lever Arm shall be supplied with a shear pin coupling hub.
- A reducer shall be a right angle gear-type with a fabricated steel drive base. The reducer shall have a ratio of 1800 to 1 to produce a speed of less than one (1) rpm. The reducer shall also have two output shafts, one connected to connecting linkage and the other to the limit controls.
- The motor shall be in accordance with Division _______, TEFC reversing, 1/2 hp minimum, and shall include a sealed waterproof conduit box. Motors shall be designed for a 3 phase, 60 Hertz, 480 volt power supply.
- Each skimmer shall have a rotational control that permits positioning the skimmer at any position between 45 degrees in one direction and 45 degrees in the direction. The gear drive of the skimmer shall have a potentiometer mounted on the rear output shaft of the gear reducer. The potentiometer output converter shall be calibrated to produce a 4 to 20 milliamp signal proportional to the position of the skimmer between it's two limits. The signal shall be forwarded to the smart system interface to allow the plant control system to signal the skimmer to the skimming position desired such that the skimmer will stop at the proper position as reported by the potentiometer. The potentiometer shall also indicate that the skimmer has returned to the neutral position at the end of its skimming operation. Proximity switches shall also be provided to insure that the skimmer does not exceed its maximum positions.
- The drive shall be equipped with three proximity switches; one switch to stop forward skimming, one switch to stop revers skimming and one for the vertical. The limit switches shall be adjustable within the limits of the connecting linkage. Proximity switches shall be 316 s/s construction.
- F. UNIT CONTROL PANEL
- GENERAL - Each of the new automatic scum pipes for the secondary clarifier tanks shall be furnished with a unit control panel consisting of forward-auto-vertical hand switch, reverse-auto-vertical hand switch, amber power "on" light, green operating light, red alarm light for motor thermal overload, timer, vertical position light,and contacts for a remote alarm. Remote contacts shall be provided for scum collector operating and motor thermal overload. Control panel shall include necessary control transformers, relays and other equipment necessary for a complete operating unit in conformance with this Section of the Specifications and Division ______. The UCP shall have a 316 stainless steel, NEMA 4X enclosure and shall be pedestal or handrail mounted near the drive. Each UCP shall be provided with a 120 VAC external power supply and all required transformers shall be provided.
- CONTROLS - Each new secondary scum pipe shall be completely equipped with an automatic drive and control panel to provide automatic forward and reverse skimming and return to the vertical position on a smart system interface with plant control system.
Manual skimmer control shall be from each skimmer control panel. Forward-Auto-Vertical, Reverse-Auto-Vertical hand switches. Unit adjustable limit switches will set forward and reverse slip angle.
- G. ANCHOR BOLTS - All anchor bolts shall be Type 316 stainless steel and shall be of ample size and strength for the purpose intended.
PART 3 - EXECUTION
3.01 GENERAL - Install in conformance with Division _________ And Section ___________. All equipment and motors shall be installed in accordance with the recommendations of the Manufacturer. The Contractor shall provide, at no cost to the Owner, all accessories and material necessary to ensure a complete working system, whether or not shown on the project drawings.
3.02 PAINTING AND PROTECTIVE COATINGS - All furnished ferrous metal components shall be given a protective coatings as specified in Section _______ of these specifications.
3.03 SPARE PARTS - The following spare parts shall be furnished for each
- Qty Item
4 ea. scum pipe seals- 4 ea. proximity switch
- 6 ea. shear pins
- 2 ea. 4-12 potentiometer
- 3.04 FIELD TESTING AND START-UP - Following completion of the installation, the contractor shall provide the service of the Manufacturer's factory-trained technician to test the operation of the scum collection system. The operation shall be free of vibration and noise. In the even the scum collection system does not operate as specified, it shall be modified as required and retested at the sole expense of the Contractor Coincident with testing of the scum collection equipment, the Contractor shall perform system test of all components as specified in Part 2 of limits. Upon completion of in-place testing, the Contractor shall certify in writing to the Owner, in triplicate, that the test was conducted in accordance with these Specifications, and that all components within the system successfully functioned as required.
- 3.05 INSTRUCTION - After the equipment has been installed, tested, adjusted, and placed in satisfactory operating condition, the Contractor shall provide the services of a Manufacturer's representative to instruct the owner's operating personnel in the use and maintenance of the equipment. The Contractor shall give the Owner formal written notice of the proposed instruction period at least ten (10) working days prior to the commencement of the instruction period. The Manufacturer shall provide a level of instruction which is adequate to train the Owner's personnel regarding use of the equipment. During this instruction period, it shall be the responsibility of the Manufacturer to answer any questions from the Owner's operating personnel. The Manufacturer's obligation shall be considered ended when both the manufacturer and the operating personnel agree that no further instruction is needed. An appropriate allowance for the instruction shall be included by the Manufacturer in the price of the equipment.
29233 106th Street East • Little Rock • CA 93543
PH: 661 944-6970 • FX: 661 944-0813
Email: info@polytechcorp.us
