Cliff stabilisation: industrial vacuum cleaners in harsh outdoor conditions

Customer:	Stump Spezialtiefbau – Karl-May Festival
Extracted material:	drilling dust from rock bore holes
Industry:	Other
Vacuum cleaner:	2 Ruwac DS 4150

Stump-Franki Spezialtiefbau GmbH was formed in 2019 from the merger of Stump Spezialtiefbau GmbH and Franki Grundbau GmbH & Co. KG. The merger resulted in a high-performing, complete service provider for specialised civil engineering that offers a broad range of services from a single source across Germany. The company is part of the international Porr Group, whose core area of expertise is reinforcement work on stone and rock.

Problem

The Chemnitz branch of Stumpf was commissioned by the Karl-May festival to handle reinforcement work on the natural background after the rock face was found to have crumbling and falling stones. Specialists from Stumpf drilled 375 holes, each 15 cm in diameter, into the rock face and installed steel anchors using a system developed by the company that employs specialised technology. These anchors, which are invisible to spectators, reinforce the rock wall.

The workers needed to extract the fine drilling dust directly at the source during the drilling work, which took many months.

Solution

Two type DS 4150 Ruwac vacuum cleaners with three-phase drive handled the job, even in the face of difficult conditions. The abrasive rock dust also placed high demands on the wear capabilities of the devices. The two DS 4150 handled the project with no downtime.

The vacuum cleaners remained on the ground, while Stumpf's drilling technicians were lifted high above the ground in the basket of a crane truck to set the drilled holes. The suction hose was routed across the rock face. The equipment was used for more than just drilling - each of the 375 holes was carefully cleaned with the Ruwac vacuum cleaners before workers injected the stabilising mass into them and sealed them once again. The large dimensions of the filter and collection container proved advantageous: Despite the large amount of dust produced, the collection containers only needed to be emptied a few times, and the vacuum cleaners saw no notable loss of differential pressure throughout the project, as it would if the filters were full.