- Drive unit has two concentric output drive shafts
- Used on solids contact and flocculating clarifiers or softeners
- Rake drive section is a low-speed, high-torque, totally enclosed gear drive with
- positive overload protection
- Turbine drive section is a heavy-duty, higher speed, totally enclosed gear drive
- The drive unit is supported by a bridge completely spanning the tank
- The drive unit has a central output shaft to drive the rakes
- Used in industrial, municipal and mining clarifiers and thickeners
- Typically used on tank sizes from 10 to 100 ft (3 to 30 m) in diameter
- Forged alloy steel main gears and pinions designed for 20 years of life calculated per
- AGMA 2001-C95
- Precision, four-point-contact main bearing, with a 10-year warranty
- Rake drive has accurate torque gauge calibrated in ft-lbf, N-m or any units desired
- Variable speed turbine drive is standard
- Alarm and cutoff switches and maximum torque limiting via shear pin or pressure relief valve
- Dry well lubrication on turbine output
- Designed for minimum maintenance with permanently lubricated rake intermediate gearbox
- Machine frame
- Main gear-bearing, turbine
- Pinion, rake
- Planetary gearbox, rake
- Torque gauge
- Primary speed reducer, rake
- Electric motor, rake
- Main gear-bearing, rake
- Electric motor, turbine
- Primary speed reducer, turbine
- Pinion, turbine
- Pinion support bearing, turbine
- Drive hub, turbine
- Drive hub, rake
E-type primary speed reducer
The E-type design uses helical gears for speed reduction. It has alarm and cutoff switches and a shear pin to provide triple protection of the drive unit. This design is used where the output speed is outside the limits of the F-type primary speed reducers or when an electro-mechanical type drive unit is desired.
F-type primary speed reducer
The F-type design uses a hydraulic pump-motor combination for speed reduction. It has alarm and cutoff switches and hydraulic relief (equivalent to a shear pin in the E-type primary speed reducer) to provide triple protection of the drive unit. This design is positive torque-limiting and will operate under stalled and semi-stalled conditions. Optional reversing rotation and variable speed are available. The torque indication and protection system is equally accurate for operation in either direction.
H-type primary speed reducer
The H-type design has all the features of the F-type primary speed reducer. It uses a stand-alone industrial hydraulic power unit. This design is used on higher horsepower and multiple pinion drive applications.
W-type primary speed reducer
The W-type design uses helical gears for speed reduction. It has shear pin and shear pin activated cutoff switch to protect the drive unit. This is simplified E-type design used where a torque gauge and adjustable alarm switch are not required.
Mechanical type variable speed reducer
The mechanical variable speed reducer is a ring-cone or a disc design. The output speed varies as the pitch-line distance between two rotating components decreases or increases. The speed variation is adjusted by turning a hand-wheel on the reducer. These reducers include a standard NEMA C-frame on both the input and output connections for easy installation and removal. The reducers provide a 5:1 variable speed range.
Electrical type variable speed reducer
The electrical type variable speed is a variable frequency drive (VFD) that controls the output speed of the electric motor. The VFD can be mounted near the drive unit or at a remote location. VFDs provide a clean, maintenance-free, and economical way of attaining variable speed. Standard features include forward and reverse, speed indication, motor overload protection, soft-start, 4-20 mA signal, and monitoring of operating conditions. These reducers provide a 5:1 variable speed range or 10:1 when used with an inverter duty motor.
Hydraulic type variable speed reducer
The hydraulic type variable speed reducer is a stand-alone industrial hydraulic power unit with a variable volume piston pump and hydraulic motor combination for speed reduction. This design is used when the rake primary speed reducer is an H-type design. A screw located on the pump is turned to change the stroke of the pump pistons and vary the amount of oil delivered to the hydraulic motor, thus varying the final output speed of the drive unit. These speed reducers provide a 3:1 variable speed range.
Example: Model S34-AF-D345
S is for a bridge-mounted drive unit; 34 is the size of the final gear pitch diameter in inches; A is the size of the secondary speed reducer; F is the type of the primary reducer; L is for a lift mechanism; 10 is the lift capacity in tons; 12 is the lift travel in inches; F is the type of the lift actuator.
- Alarm and cutoff switches
- 3 sets of O&M manuals
- 6″ torque gauge indicating real torque (not available on H-type primary reducer)
- 4-20 mA torque transducer
- Bi-directional operation (available for F and H-type primary reducers)
- Loss motion switch
- 4-20 mA lift position transducer
- Variable speed, turbine
- Variable speed, rake
- Special electric motor
- Oil heater (available for F and H-type primary reducers and main gear housing)
- Oil temperature switch
- Oil level switch
- Explosion proof switches