Muhr Trashrack cleaner in Zambia

Autor: David Tscholl , 29.05.2014

With the Kafue River Dam project in Zambia, German-based hydro-technology provider Muhr adds another highlight to its list of numerous international reference projects.

The system installed at Kafue was a HYDRONIC M-5000 hydraulic muti-functional trash rack cleaner. With a maximum boom length of 36 m and an overall weight of 106 tons, the installation project had quite a few challenges in store for the engineers.

The Kafue river dam is an essential lifeline for Zambia. Besides being used for hydropower generation, the river also plays an important role in local private and industrial agriculture. Due to its low storage capacity, however, the dam has been integrated into a system of several interconnected dams. This also includes the Itezhitezhi dam further upstream in the Kafue national park, and the Lower Kafue Gorge dam, which is still in its planning stages. The overall capacity of the Kafue river dam system amounts to 900 megawatts. The most recent construction work performed on the power plant facilities was an extension in 1972. Now operator ZESCO Ltd. has decided to have the facilities fitted with a brand-new trash rack cleaning system by renowned German-based provider Muhr GmbH.

The completion of the manufacturing work was followed by the official handover in Brannenburg in southern Bavaria. When it took place in November 2012, the customer was represented by three members of staff who had travelled all the way from Zambia. When the delegation arrived, they were impressed ‒ first by the snow in the pre-alpine Bavarian valleys, and then again by the sheer size of the trash rack cleaner. The hydraulic multi-functional trash rack cleaning system that was ordered is a HYDRONIC M-5000, which has a 36 m boom designed for cleaning depths of up to 27 m. The hydraulic articulated boom has a lifting power of 70 kN and a pivoting range of 330 degrees. Being only 16 m wide, the trash rack itself is equipped with a detached pontoon system. This construction requires the pivot arm and rake to be controlled with very high precision. The sophisticated control unit used for this purpose is based on a redundant multi-level security concept, and it can monitor the position of the telescope arm with extremely high precision. Also, the machine is equipped with a dual cleaning head holding frame for a cleaning rake or hydraulic orange-peel grab. Included with the order was the required rail system.

Packing up a bulky 135-ton device and shipping it to Zambia in southern Africa turned out to be a huge logistic challenge, but one that Muhr’s experts managed perfectly, thanks to their extensive international project experience. The tricky bit was coordinating customs procedures with the shipping schedules of various haulage companies at home and abroad. It took nine heavy-duty trucks to move the machine parts from southern Bavaria to the lading port in Hamburg. This was not at all an easy task, considering the huge dimensions of the 16 m telescope arm. From Hamburg the machine went by ship to Walvis Bay in Namibia. For the last part of its journey, the trash rack cleaner was hauled by truck all the way across Namibia to its final destination at the Kafue Gorge Power Station in Zambia.

When the machine arrived, the installation team was all ready and waiting. The installation process itself had been planned meticulously in advance to be prepared for any contingencies. This included a comprehensive selection of tools and appliances, which are hardly available any more in Zambia. Unloading the machine parts also required careful adjustment to local conditions. In Germany, a freight of this size would be unloaded using a mobile crane with 100-ton hoisting power, but the capacity of the only crane available on-site was only half that. But thanks to the experience of the installation engineers, all parts were safely hoisted off the trucks and installed without any problems.

Besides allowing them to prove their excellent technical qualifications, the project also required a lot of social skills from the engineering team members. They had to coordinate and delegate the tasks for the installation workers. Fortunately, Zambia’s official language is English, and so communication was no problem. For the German team, the project was an exciting adventure, and everyone involved was happy to contribute a little to cross-cultural understanding. The project even gave rise to some long-term friendships, which are still kept over the Internet and social networks. “The Kafue project in Zambia is another highlight on our list of international projects,” says Erhard Muhr.

“Collaborating with international customers is both educational and exciting ‒ and it’s a lot o fun, especially if working together is as successful and satisfying as in this case.”

Tags: , , , , , ,