SEWER CHEWER ® Wastewater / Sludge GrinderSPECIFICATIONS
Suggested Typical Specifications
1.0 SCOPE
This specification describes the installation and equipment to be furnished for the wastewater / sludge grinder(s) and the accompanying grinder controller(s) to be installed as shown on the plans and specifications. Each of the ____ unit(s) shall include grinder, motor, speed reducer, and grinder controller(s). In-line installations only shall include flanged hoppers. Grinder shall be capable of processing sludge or solids (normally found in wastewater flow) continuously either wet or dry. Sewer Chewer ® Grinder(s) for channel and wet-well installation shall be Model No. CC-______and for flanged in-line installations shall be Model No. SC-______.
2.0GENERAL
2.1 Reference Standards - The grinder(s) and controller(s) shall be provided in accordance with the following industry standards:
2.1.1 Grinder
2.1.1.1 ASTM A48-83: Standard Specification for Class 30 Grey Iron Castings
2.1.1.2 AISI 4140 Heat Treated Hexagon Steel Bar
2.1.1.3 AISI 4130 Heat Treated Alloy Steel
2.1.1.4 43-48 Rockwell C Hardness Rating
2.1.1.4 ANSI B16.1.125 Flanges
2.1.1.4 AFBMA (Anti Friction Bearing Manufacturers Association)
2.1.2 Motor
2.1.2.1 NEMA Standards
2.1.2.2 IEEE Standards
2.1.3 Speed Reducer
2.1.3.1 AGMA (American Gear Manufacturers Association)
2.1.3.2 SM-Cyclo Service Factor Ratings
2.1.4 Grinder Controller
2.1.4.1 NEMA (National Electrical Manufacturers Association)
2.1.4.2 UL (Underwriter Laboratories)
2.1.4.3 IEEE (Institute of Electrical and Electronics Engineers)
2.1.4.4 NFPA (National Fire Protection Association)
2.1.5 Grinder shall be designed and manufactured in the USA, and shall conform to "Buy American" and "Domestic Steel Procurement" requirements.
2.2 Testing and Quality Assurance
2.2.1 Manufacturer shall factory run test each completely assembled grinder to verify conformance to manufacturing quality standards and to assure optimal grinder performance.
2.2.2 In-line Units shall be factory tested and certified with a hydrostatic test to 90 PSI.
3.0WASTEWATER / SLUDGE GRINDER
3.1 Operation
The grinder shall be a dual shafted, low speed, high torque wastewater / sludge grinder. The grinder shall utilize a cutter/spacer arrangement on each shaft that intermeshes with the cutters/spacers on the other counter-rotating shaft in a helical pattern. The cutters shall be cam shaped with five (5)-cutting teeth and shall have five (5) additional cutting surfaces on the mating faces on each side of the cutter to provide maximum solids reduction. This cutter arrangement shall provide an efficient cutting, grinding, shearing, shredding, and tearing action while allowing maximum flow of fluid and solids reduction. Cutters and spacers shall be positively locked to the hex shaped shaft through a hex shaped inner bore. The Cutter/Spacer stack will be secured through the use of locknuts that are threaded to the shaft. The cutter /spacer tolerance may be maintained by simply adjusting the locknut on the bottom of the shaft. This solid waste reduction machine shall be designed to be used in sludge / wastewater and will utilize bearings and seals that are appropriate for sludge/wastewater use.
3.2 Construction and Design
3.2.1 Bearing Housing Covers
Both top and bottom bearing housings and covers shall be cast of ASTM A48-83 Class 30 Grey Iron. Top housing shall be dowelled for positive alignment between the grinder and the reducer pedestal. Bottom cover shall allow easy access to shaft locknuts, which allow adjustment of the cutter stacks. Top and bottom housings shall be sealed with cloth inserted neoprene gasketing.
3.2.2 Side Rails
Side rails are cast of ASTM A48-83 Class 30 Grey Iron. Side rails shall be concave in design that follows the radial arc of the cutter diameter. Side rails shall feature a deflection area that directs larger solids into the cutting zone of the grinder.
3.2.3 Cutters and Spacers
3.2.3.1 Cutters and spacers shall be made of AISI 4140 Alloy Steel. Cutters and spacers shall have a minimum hardness of 43-48 Rockwell C, and precision ground to size. Mating faces shall be ground to a minimum #63 micro inch Root Mean Square (RMS) finish to assure flatness across the face.
3.2.3.2 Cutters shall be of a 5-tooth design, and will have additional shearing surfaces on the cutter faces to provide efficient reduction of solids.
3.2.3.3 Cutters and spacers shall feature a cast hex bore to eliminate the need for secondary shaft fastening.
3.2.3.4 The cutter design shall feature sufficient overlap to ensure constant contact with the intermeshed cutters.
3.2.3.5 Cutters shall be a maximum of 4-3/4" in diameter and exert a minimum force of 1540 pounds at the deepest point on the cutting edge.
3.2.4 Shafts
Grinder driving and driven shafts shall be manufactured of AISI 4140 Heat Treated Hexagon Steel with a minimum tensile strength rating of 149,000 PSI to minimize shaft deflection.
3.2.5 Bearings
Bearings shall be double sealed, oversize, solid-lube packed, Conrad-Type ball bearings. Bearings shall be a permanently lubricated design that does not require any external lubrication. Bearings shall be designed to protect against contamination by completely filling the bearing cavity with a washout resistant cured polymer. This saturated polymer shall release lubrication to the bearings on demand. Bearings shall be commercially available, the use of proprietary bearings shall be considered unacceptable.
3.2.6 Seal Assembly
Bearing protection shall be accomplished through a dual-element bearing isolator of 416 stainless steel with Viton
o-ring that is preceded by a protective viscous fluid barrier and enhanced with a carboxylated nitrile seal for secondary bearing protection. Pressure seal shall be rated at 90 PSI by the manufacturer. The use of external lubrication or flushing is not required and shall be considered unacceptable. Seals shall be commercially available, the use of proprietary seals shall be considered unacceptable.
Optional – High Grit Seal:
The bearings shall be protected by mechanical seals. The seal face material shall be tungsten carbide. The mechanical seals shall be rated at 90 PSI by the manufacturer. The use of external lubrication or flushing is not required and shall be considered unacceptable. Seals shall be commercially available, the use of proprietary seals shall be considered unacceptable.
3.2.7 Nameplates
Equipment shall be permanently affixed with a stainless steel nameplate that identifies the model number and sales order number of the grinder. Nameplate will clearly identify the name and address of the manufacturer.
3.2.8 Hopper Flanges (In-line Units Only)
Hopper Flanges shall be cast of ASTM A48-83 Class 30 Grey Iron. Flanges are 125 lb. ANSI flat faced flanges and are drilled for standard bolt patterns. Inspection covers shall be top mounted for easy access and shall be ASTM A36 steel. Hopper flanges shall easily bolt up to grinder and provide a positive seal to the face of the grinder. Each hopper shall be equipped with factory drilled and tapped drain plugs. One-piece cast housings that do not allow for worn component replacements shall be considered unacceptable.
3.2.9 Hopper Gaskets (In-line Units Only)
Hopper gasketing shall utilize a self-forming PTFE sealing tape. These gaskets shall feature a one sided adhesive strip to simplify installation on vertical surfaces.
3.2.10 Painting
Each grinder unit shall receive one (1) coat of an environmentally-safe machinery enamel coating with a high solids content (Optional: one (1) coat of high solids content epoxy coating)
3.3 Installation (Choose One)
The contractor shall install the grinder in accordance with the manufactures instructions and drawings. Anchor bolts, gaskets and other required hardware and supports shall be furnished by the contractor.
3.3.1 Channel Type Sewer Chewer
A channel frame assembly will be furnished that will mount directly in the channel and will hold the grinder(s) in place without fastening and allow the grinder to be easily removed for inspection and maintenance. The frame assembly shall be constructed of (Choose: steel angle with environmentally-safe machinery enamel coating with a high solids content (Optional: one (1) coat of high solids content epoxy coating) / 304 Stainless Steel / 316 Stainless Steel).
3.3.2 Wet-Well Mounted Sewer Chewer
Sewage grinder shall be directly mounted at the influent point of the wet well. A wall mounted frame assembly shall be supplied by the grinder manufacturer and will be constructed of (Choose: steel angle with environmentally-safe machinery enamel coating with a high solids content (Optional: one (1) coat of high solids content epoxy coating) / 304 Stainless Steel / 316 Stainless Steel). This frame assembly will be designed to secure the grinder in the wet well without bolting it down and allow the grinder to be raised and lowered without disconnecting or entering the wet well. One guide rail top bracket and quantity _____ intermediate guide rail brackets (Additional bracket required for each 10 feet of depth). Brackets will be constructed of (Choose: 304 Stainless Steel-Std/ 316 Stainless Steel-Opt).
Please note: 2" Schedule 40 guide pipe to be furnished by others.
3.3.3 In-Line Mounted Sewer Chewer
In-line unit(s) shall be fitted and installed per the manufacturer's instruction and drawings. Each grinder shall be properly supported so as to not produce strain on the piping system. Grinder shall be mounted so that it may be easily adjusted without removal from the pipeline.
4.0DRIVE (Choose One)
4.1 Standard Integrated Gear motor
The gear motor shall be TEFC design, 3 HP/5 HP (5 HP standard on CC-32 and CC-40), 1750 RPM, 208/230/460V, 60 Hz, 3 Ph. Motor shall have a S.F. of 1.15 and have an efficiency of not less than 84.9% / 86.8% at full load and the power factor not less than 78.9 / 84.9% at full load. The motor shall have an integrated cycloidal speed reducer that directly accepts the motor output shaft as an integrated input shaft to the reducer.
The motor speed shall be reduced to the driving shaft at a ratio of 29:1 through a grease filled cycloidal reducer. This unit will be rated for "Heavy Shock" loads and be capable of accepting 500% momentary, intermittent shock loads without damage or reduction of rated life. Reducer shall have a minimum full load efficiency of 90%. The reducer is coupled to the grinder with the use of standard commercially available couplings. The driven shaft RPM is further reduced by use of a 12 tooth gear on the driving shaft and 18 tooth gear on the driven shaft. This gear reduction allows the driving shaft to turn at 60 RPM while the driven shaft turns at 40 RPM insuring a shredding action.
4.2Optional Submersible Integrated Gear Motor
Hermetically sealed, TENV, submersible type motor, rated for continuous in-air operation. Features include Class “H” insulation, 1.0 service factor at 40° C ambient temperature, high strength AISI 11L41HR alloy steel shaft, high pressure lip seal, automatic reset N.C. series connected thermal overload protection, pre-lubricated shaft bearings designed for B-10 life 30,000 hours minimum, ASTM A48-83 Cl 30 Cast Iron construction, epoxy sealed "non-wicking" cable entry system and ____ (25 ft. std) feet of multi-conductor power and control cables. The motor construction shall be of explosion proof, TENV-TEXP design and capable of being certified for use in Class I, Group I, Division C & D hazardous locations by Factory Mutual (F.M.). Output shaft of the submersible motor shall also be the direct input shaft of the speed reducer. The grease filled cycloidal speed reducer shall feature a reduction ratio of 29:1. The reducer unit will be rated for "Heavy Shock" loads and be capable of accepting 500% momentary, intermittent shock loads without damage or reduction of rated life. Reducer shall have a minimum full load efficiency of 90%. The reducer is coupled to the grinder with the use of standard commercially available couplings. The driven shaft RPM is further reduced by use of a 12 tooth gear on the driving shaft and 18 tooth gear on the driven shaft. This gear reduction allows the driving shaft to turn at 60 RPM while the driven shaft turns at 40 RPM insuring a shredding action. Motor shall be manufactured by the grinder manufacturer.
4.3 Optional Non-Integrated Motors
The motor shall be ___ HP, 1750 RPM, 208/230/460 volt, 60 Hz, 3 Phase or 115/230 volt, 60 Hz, 1 Phase. Motor shall be a cast iron/aluminum frame, ______enclosure, C-face with a service factor of _____. Motor shall have a full load minimum efficiency of ______% and a power factor of not less than ______% at full load.
The motor speed shall be reduced to the drive shaft at a ratio of 29:1 through a grease filled cycloidal reducer. This unit will be rated for "Heavy Shock" loads and be capable of accepting 500% momentary, intermittent shock loads without damage or reduction of rated life. Reducer shall have a minimum full load efficiency of 90%. Reducer will be coupled to motor and grinder with the use of standard commercially available couplings. Motor pedestal shall directly bolt to reducer and accept standard C-Face motor. The driven shaft RPM is further reduced by use of a 12 tooth gear on the driving shaft and 18 tooth gear on the driven shaft. This gear reduction allows the driving shaft to turn at 60 RPM while the driven shaft turns at 40 RPM insuring a shredding action.
4.4 Drive Arrangement (Choose one)
4.4.1 STANDARD HEIGHT
A standard height Sewer Chewer shall be furnished with the gear motor directly connected to the grinder unit using a pedestal and coupling.
4.4.2. SUPPORT PIPE
An elevated drive assembly shall be furnished for each Sewer Chewer machine. The gear motor shall be mounted on a steel tube support assembly ______feet long (Refer to factory if over 6 ft.). The assembly shall be complete with a flexible shaft extension between the gear motor and the grinder assembly. The support pipe shall receive one coat of coal tar solution.
4.4.3. PROTECTION PIPE - An elevated drive assembly shall be furnished for each Sewer Chewer machine. The gear motor shall be mounted on a floor plate on a floor above the grinder machine installation and shall be connected to the grinder unit by means of a flexible shaft. The intermediate shaft shall be enclosed by a galvanized steel tube protection assembly 6 ft. long.
FLOOR PLATE - There shall be furnished one 16 inch (or 30 inch optional) square steel floor plate complete with expansion type anchor bolts. The floor plate and curb frame (if furnished) will also receive one shop coat of rust inhibitive primer and one finish coat of machinery enamel.
5.0HYDRAULIC DRIVE UNITS
5.1 HYDRAULIC DRIVE
Unit shall be driven by a hydraulic pump and motor package. Hydraulic drive pack will be remotely located, and use flexible hydraulic hose to connect to the grinder. Hydraulic pump shall be driven with a TEFC, C-Face, 5 HP (7.5 HP Optional), 1750 RPM 208/230/460V, 3 Ph, 60 Hz electric motor. The hydraulic drive package shall be furnished complete with the following:
5.1.1 Electric motor & high efficiency positive displacement hydraulic pump.
5.1.2 Hydraulic Fluid Reservoir with the following features:
5.1.2.1 Removable Top and filler breather.
5.1.2.2 Liquid level and temperature sight gauge.
5.1.2.3 10 Micron return line filter.
5.1.2.4 Oil Level switch set at 60% of full level.
5.1.2.5 Oil Temperature switch set to 160°.
5.1.2.6 0 to 3000 PSI Pressure gage and snubber.
5.1.2.7 Pressure switch designed cut out at 2850 PSI.
5.1.2.8 Internal relief valve designed to cut out at 2900 PSI.
5.1.2.9 20 Gallon capacity hydraulic reservoir.
5.1.2.10 Adjustable back pressure valve.
5.1.2.X Rain Resistant Duty Unit - Includes motor cover and grommeted electrical connections (Optional).
OR
5.1.2.X Cold Weather Duty Unit - Includes 1500 watt internal hydraulic fluid heater and adjustable thermostat (Optional).
5.1.3 Four-way, three-position directional control valve will have a normal return setting. The valve will be actuated by the start button of the control panel to switch to the forward position. If an overload condition is detected, the pressure switch will signal the PLC in the controller to automatically switch the solenoid valve to the return position, allowing the grinder to briefly pause before moving to the reverse position. The valve will be again signaled by the controller to briefly pause before continuing normal forward operation. This cycle will continue for ______attempts in a ______second window before grinder will shut off and signal a grinder overload alarm on the panel.
5.1.4 Hydraulic drive pack shall be furnished with appropriate contacts to control panel to communicate reversal logic and to signal low oil and high oil temperature conditions.
5.2 Hydraulic Motor that will couple to the grinder with the use of standard commercially available couplings.
5.3 _____ feet of flexible hydraulic hose shall be provided for connection of hydraulic pump to the hydraulic motor on the grinder. Hose shall be rated for a minimum working pressure of 3500 PSI. (Hard piping recommended over 50 ft.).
5.4 Hydraulic pump shall provide a flow of ____ GPM (nominal), and will operate the driving shaft of the grinder at approximately ____ RPM.
6.0GRINDER CONTROLLER
6.1 Operation-Digital Panel (Standard)
Normal operation is continuous forward rotation. When an impediment condition is detected, the controller shall instantaneously stop the rotation, pause, and momentarily reverse the grinder rotation to clear the obstruction. When the jam is cleared, the controller will return to standard forward operation. If the obstruction persists, the controller shall repeat the reversal cycle for a total of three (3) times within a 30 second window. If the grinder attempts a fourth reversal, it will shut down, display grinder jam on the LCD screen and sound the horn once every 10 seconds until the alarm is reset.
6.2 Construction and Design
6.2.1 Controller enclosure shall be of a NEMA 4X FRP (Fiberglass Reinforced Polyester) (NEMA 4X Type 304 SS & 316 SS optional). Enclosure shall feature stainless steel hinges and latches for corrosion resistant operation. Latches shall be capable of being padlocked to assure safety and security.
6.2.2 Controller shall include an internally mounted circuit breaker that is operated with a pass through lever that will not allow the controller door to be opened when the lever is in the "ON” position.
6.2.3 Controller shall include a door mounted digital interface. This interface shall provide messaging, operating and programming functions.
6.2.3.1 An LCD display will provide text messages to communicate the operation of the grinder. Operation buttons will be directly incorporated in the keypad of the interface.