For the coarse filtration of raw water intake structures at:

• Hydro power stations
• Nuclear and fossil power stations
• Chemical plants
• Potable water treatment plants
• Sewage treatment plants
• Water reclamation facilities
• Land and storm drainage pumping stations
• Various screening applications

Hydro Bosker Raking Machine

The Hydro Bosker Raking Machine is designed for highly effective bar screen cleaning in a wide range of applications with features specifically designed for hydro power stations. Simplicity of design and efficient debris handling make the Bosker Raking Machine the ideal solution for cost efficient cleaning of single or multiple bar screens. Our engineers customize every Raking Machine to site and application specific parameters. Retrofit into existing installations is simple and there is usually no need for expensive civil modifications. The Bosker Raking Machine has continually evolved since its introduction in 1960 and its success has been reinforced by Brackett Green’s century of experience in mechanical water filtration. Today, there are more than 500 Boskers in successful operation worldwide. It is this unique combination of efficient design and long term in-depth field experience that is your assurance of decades of reliable and economical performance.

The Problem

Conventional trash rakes can require complex civil works, require large amounts of space to operate and have limited abilities to remove oversized, awkward debris such as tree trunks. Conventional trash rakes also have difficulty removing fibrous material that has become entwined in the screening bars. These trash rakes merely push such debris deeper into the bar screen, compounding the effects of headloss and excessive velocities through the bar screen. Additionally, once a conventional trash rake has removed debris, a second debris handling system is required, adding to costs, complexity and maintenance. Conventional rakes have difficulty raking multiple bar screens requiring either a rake for each screen or complex, labor-intensive systems to traverse between screens and must be manually operated.

The Solution

The Hydro Bosker Raking Machine is a trash rake cubed. It effectively does the work of three conventional machines — a trash rake, conveyor and debris loading system. There is no need for multiple trash rakes, conveyor belts or double handling of debris. The Raking Machine eliminates the need for time consuming debris rehandling and provides for 24-hour coverage in case of nighttime screen blockage. Loading debris directly into a dumpster or trailer eliminates the need for additional handling. Open construction means an uncluttered screen deck. If required, Brackett engineers can include bends in the overhead monorail to access multiple screens or remote dumpsites. Operation is fast and simple. Once installed, the Bosker Raking Machine can operate automatically or a single worker can control it manually via a wireless remote or plug in pendant.

The Process

At the start signal in automatic mode, the Bosker Raking Machine travels to the designated screen area and stops over its first pickup point. The gripper descends to the bottom of the screen, collecting debris in its jaws. Cylinders close the gripper and the hoist elevates the gripper and debris to the trolley. The trolley and gripper return to the dump area, where the gripper opens, releasing debris into the hopper, trailer or other dumpsite. The Raking Machine then moves back to the second pickup point at the screen, continuing the cycle until the selected screen area is clean.

Other Features

Capacities range from 550 lbs. through 6,600 lbs. Grippers are available in widths of up to 16 feet, constructed of galvanized carbon steel, stainless steel, or aluminum-bronze (for hazardous applications). Powerful hydraulic cylinders handle awkward debris easily. Optional curved track allows for maximum flexibility of debris removal. Descending cleaning prevents skipping over large debris. There is no hair-pinning or tangling of debris due to precisely matched tine-to-bar spacing and the deep penetration of the tines between the bars. All models are available in single or dual-speed versions. A patented (U.S. Patent No. 5,718,771) RTTR version (Retractable Traversing Trash Rake) is also available for easy adaptation to deck railroad tracks. The Bosker Raking Machine is able to clean multiple screens and remotely discharge debris. Drives are protected within the track assembly. The Bosker’s smart design means trouble-free operation. If, for example, the gripper is unable to submerge due to a large buoyant object, it will close and cease to descend, preventing possible cable entanglement. Locating the hoses behind the hoist cables reduces the chance of damage by floating debris. Mounting the hydraulic cylinders directly on the gripper keeps the number of submersible moving parts to a minimum. No moving parts are permanently submerged. All models operate on the same principle — either by manual remote or automatic PLC control. Ultrasonic differential controls are also available. Telemetry data from alarms and level differential devices can also, if required, be transmitted to a central control room.