The mechanical rake screen, mainly used in municipal sewage treatment plant,residence community pretreatment device,municipal sewer pipeline,running water factory and power plant cooling water etc water inlet to make sundries separation,; it also can used in textile,fruit,aquatic product,paper making,wine making ,slaughtering,tannery etc industry manufacturing technique to make washing or pretreatment screening, it is one kind of ideal solid liquid screening equipment. Â The mechanical rake screen is driven main shaft rotating by driven device, the sprocket in main shaft two sides to make traction chain do rotary montion, uniform distribution rake tooth in circular chain, the rake spacing and bar screen spacing staggered paralleling. Â When rotational motion move rake tooth insert confirm bar space move ascending, the suspended solid which intercept by bar screen was scrape to platform upper end discharging position, and the screen residues can discharge into conveyor or residues cars .
Performance parameter
Drawing 1-1
Â
 item
code
RemarkÂ
Outer size Â
Total screen width
B
   1100mm
  discharge residues height
H2
   800mm
 bar space gap
δ
50mmÂ
 bar thickness
Â
8mm
 bar depth
Â
50mm
inclination angle Â
α
   75 °Â
  Main screen height
H3
  6000mm
Total height
H4
9000mm Â
 base and install sizeÂ
 channel depth
H1
  6800mm
 Channel width
W1
 1200mm
expansion bolt
6-d
6-M16
Â
working manner  :manual control or automatic control
Â
 Votlage
 380v,3ph,50hz
Â
  Technical performance and structure feature
Adopt equal interval linear type bar, installation in incline manner, installation angle is 75°,  and in front of screen adopt circulate chain tractive front-loading rake institutions to make remove scrubbing.
Bar screen can according to timer or before or after water level difference start in front of screen, it can meet intercept and rake remove bigger particles rubbish etc sundries in water.
Bar screen in the condition of reaching design flow rate can be 24 hours continuous operating, meanwhile it can intermittent operation and can be normal operation after long time stop.  In this project, we set every operate 30 minutes, stop 60 minutes, in such circulating, during the stop 60 minutes, if there has storm happen, the channel liquid level will reach raise, when it raise to 2m, the liquid level probe will given alarming, at the same time, the mechanical rake screen will automatic  continuous operating , till liquid level decline to normal 1.5m, the screen return to initial operation state: every operate 30 minutes, stop 60 minutes.
The rake bar screen restore operation after interruption, the rake bar sewer device can remove accumulate screen residues in fully obstructed screen.
The bar screen bracket,frame and each exercise framework all was outdoor type, all components design to guarantee its with longest service life in the worst environment.
Structure feature
 screen bar
Screen bar is composed of parallel flat steel, material adopt stainless steel, up and down ends fastening, the bar spacing is 20cm
The screen bracket dimension and corresponding to water channel width, and using stainless steel bolt confirm with bracket, bar fix in the frame. Â
The bar screen frame safety reliable confirm in reinforced concrete channel, the interspace between frame and channel wall adopt flexible baffle ward off sewage pass by screen side. Flexible baffle connect together with frame.
Each bar sectional form is rectangle, when rake tooth gearing with bar, rake tooth with bar vertical direction has certain inclined angle, to prevent smaller sundries accumulate in sewage.
The guide rail in bar screen sides can prevent screen residues immerse and influence mechanical rake screen working.
 water baffle : Â
 The water battle position from bar screen main body till rake tooth discharge residues position, water baffle permit rake tooth in operation  in case fallen material again block to bar screen upstream.
 rake bar device
Rake bar can scrape clear the rubbish in front surface and sides. When screen occur blocking, rake tooth can't upward traction, it can make rake tooth diversion operation or make rake tooth automatic lifting stretch into bar after pass by obstacle.
Rake bar and annular chain rigid coupling , and adopt chain in bar sreen two sides guide rail mobile mode, make rake bar upward traction along bar front.
Chain tension device: Â Â in long term application ,due to temperature variation,loading uneven,wear abrasion etc can lead to chain extension or shrink, using tension device can adjust chain and chain wheel tensity at any time.
The screen rake tooth is composed of by supporting pipe and rake tooth plate. The rake tooth plate upside in operation insert into bar screen water bottom block grid, used to eliminate the rubbish in water bottom block grid, to make bar screen bottom won't have dirt pile up dead space. Â
 Driven device and shield shell cover
The driven device is composed of motor,gear reducer,chain rotation device etc. gear reducer adopt Chinese famous brand, motor rotary efficiency high,low noise,long service,operation steady reliable.
Chain rotation device: Â equip with chain tension agencies and mechanical overloading protective device. Mechanical overloading device adopt safety pin structural style.
The drive shaft has enough strengthen and stiffness, to bear bending moment and torque simultaneous working loading.
The motor electric current suitable for 380V,3ph,60HZ; motor rated power is bigger than maxi real consume power about 10%.
(5)  Guiding device   The guiding device of bar screen is composed of guide pulley, respectively place in rack two sides upper and lower part, main function is change bar screen rake tooth moving direction.
 water bottom block grid
The main function of bar screen water bottom block grid is intercept water bottom rubbish, prevent rubbish flow into screen back from water bottom. The water bottom block grid intercept rubbish was scrape away by upside rake tooth. Â
Noise: mechanical rake screen overall noise less than 80dB (A)
Anticorrosion: all material suitable for sewage corrosion ring.
