Well known for their reliable hydropower systems, solution provider Muhr introduces a new, innovative protective screen drum system as the latest addition to their extensive product range.

As an alternative to horizontal trash rack systems, the Bavarian-based company’s patented RO-TEC screen drums combine high efficiency with optimum installation and maintenance characteristics while ensuring ecological compatibility.

The way the Muhr screen drums work is simple, yet extremely efficient. The screen drum consists of a cylindrical trash rack screen that rotates about its central axis. A built-in electric motor unit keeps the drum in constant rotary motion. This causes the collected floating debris to be pushed towards a wiping strip, where it is washed away by the drag flow, resulting in a self-cleaning effect. As it integrates easily into existing facilities without the need for extensive constructional work, the drum system with its self-cleaning capabilities helps to save costs and effort when it comes to debris removal. Another welcome characteristic of the new technology is its high level of fail-safety, as each drum unit is equipped with its own motor, which allows it to operate independently from other units. Naturally, the motor units are 100 per cent watertight, which means the entire screen drum system can be flooded without risk of damage.

Benefits for operators
Aside from smooth, trouble-free operation, a key requirement for operators is that the units must be easy to service and maintain. This is why ease of maintenance was a top priority in the design of this brand-new protective screen drum system. As a result, the drums are not only quick and easy to install, they can be removed just as easily for maintenance purposes. This way, any repair work – although unlikely to be necessary, thanks to the use of durable technology and only few moving parts – can be performed safely and conveniently “on dry land”. In the meantime, stop logs can be fitted to the drum’s guide rails to ensure continuous operation of the facility. Another big plus of the new drums is the extremely short installation procedure. De-livered by lorry, the units are lifted onto the guide rails (these must be provided in advance at the building site) and installed properly by Muhr technicians. The entire procedure takes no longer than 60 minutes. Once installed and electrically connected, the drums are ready to go.

Screen drums made to measure
Depending on individual project requirements, the screeen drums can be custom manufactured to suit the operator’s needs. Screen Drum sizes range between 500 mm and 2.800 mm in diameter and 500 mm to 10.000 mm in height. The screens are made from galvanised high-grade steel and are available in slot widths from 2 mm to more than 50 mm. Operators can choose from a variety of grid profiles, depending on the slot width and ambient conditions at the installation site. A potentially unlimited number of drums can be combined into a single screening system to accommodate facilities of any size. The RO-TEC drums are suitable for water sampling points of any kind, cooling water and process water treatment plants, and, of course, hydropower facilities.

Ecologically superior
Fish friendliness’ is another beneficial feature of the screen drum. Thanks to the specially designed screen profile, water-based animals cannot get caught in the device or sustain injuries from sharp edges. Also, the round, drum-shaped design provides about 1.5 times the surface area of standard screens, which reduces the water flow velocity around the device. This means a considerably lower risk of fish being sucked into the system. With its low construction height, the components of this patented screen system also integrate smoothly into existing river landscape. What is more, the resource-saving operation of the device requires no oils or other lubricants, which eliminates the need for the disposal of problematic waste.