Mechanical Fine Front-Raked Screen
The Tecroveer range of Mechanical Front Raked Screens is available in the following sizes:
- The screens are available in sizes from 300mm to 1500mm
- The screens will be able to accommodate flows from 300kl to 50 Ml
The rectangular frame is laser cut for maximum accuracy and is recessed to accommodate the chain guides and idler sprockets and is set in the channel at approximately 75° to the horizontal. The frame may be grouted into position in recesses in the channel walls and invert or braced at coping level on a spindle bar permitting the unit to be swiveled from the channel.
The frame is fully welded to the sole plate, the debris plate and the discharge chute. At the upstream face of the unit, box-section cross-members are securely welded to the side members of the frame at regular intervals thereby forming a rigid frame for the screen cladding.
The screen bars are accurately set in laser cut slots at the required spacing and solidly secured to the brace-plates for bolting onto the screen frame, for easy removal of the screen field. Intermediate stiffening supports perpendicular to the bars are used to brace the screen bars at the downstream surface of the screen field. These supports are welded to the screen bars for extra support and each screen bar is individually welded to the stiffening support.
The sole plate is curved to induce screenings and debris in the lower level of the flow to be directed onto the lower portion of the screen bars thus preventing accumulation at the foot of the screen. The leading edge of the sole plate is level with the channel invert.
The raking bars with tines are cold-formed from a single laser cut plate to ensure complete stiffness across the full width of the bar. When engaged these tines form an angle of 5° to the plane of the screen field.
Each raking bar is attached and accurately aligned to the drive chain within the side members of the screen frame utilizing suitably fabricated links. The tines are set to engage the screen field across the full width.
Chains, guides and sprockets
The chains consist of stainless steel links that are joined at each ertelyte roller with a stainless steel pin. Chain guides are fully adjustable and securely fixed to the side members of the screen frame for the full length of travel of the chains.
Idler sprockets or bottom turn-overs are located at the lower end of each side member of the screen frame and are laser cut from 20mm stainless steel plate. Each sprocket also contains a fully welded bush housing a self-lubricating composite bush.
Sprockets are retained on their respective stub axles utilising a removable retaining mechanism to facilitate maintenance.
The drive shaft at the head of the screen frame is fitted with two chain sprockets that are mounted with key-ways onto the shaft.
The drive unit is selected for continuous operation and consists of a shaft mounted gearbox mounted directly onto the drive shaft to protect the gearbox bearings from undue stresses due to possible misalignment.
The drive bearings are of the conveyor take-up type to enable the drive chains to be correctly tensioned and the raking bars to be accurately positioned across the screen face. No special tools or dis assembly of the unit is required for this operation.
The cleaning mechanism comprises a single bar that engages each raking bar as it rises above the upper edge of the screening retention plate. This discharge scraper engages the full width of the raking bar to ensure effective screenings removal.
The discharge height may be altered to suit each specific application and the discharge chute may be entirely enclosed for flange mounting onto the screenings press or conveyor.
Electrical Control Panel
Each screen is supplied complete with a proprietary electrical control panel housing the required control equipment. Differential level control may also be offered as an optional extra.
to suit in fluent.