ITH Supports The Maintenance Of Bolted Connections At The Zugspitze Mountain Station

The regular maintenance works on the steel structure of the mountain station on the Zugspitze have been completed much faster than usual this year. At Germany's highest workplace on 2,943.75 metres above sea level, ITH Bolting Technology supported the inspection of the bolted connections with qualified technical advice, fast service and flexible bolting tools.

Germany's highest workplace requires a head for heights - ITH bolting tools prove flexible use

The maintenance work was comprehensively accompanied by ITH Bolting Technology: 

1.Technical advice on the pre-selection of the hydraulic torque wrenches used and the hydraulic equipment.

2.Provision of the tools as well as proper instruction of the technicians on site.

3.Qualified assembly during the inspection of the screw connections in compliance with all safety standards.  

"It was something special for us to work at this height and under these conditions. Even though we are familiar with working on construction sites with height safety equipment, the Zugspitze is an exception for us - you definitely can't be afraid of heights," says the ITH bolting specialist Jens Borggrebe. 

"It was impressive how the technicians on site dealt with the height and the view. The enormous experience makes everything look much more natural and easy. Our bolting tools proved their worth and were a relief in the circumstances - especially our battery-powered hydraulic unit. We didn't have to run any power cables, so we were able to change the application spots quickly when we finished checking a bolted joint."  

The technicians on site drew a positive balance: "We were able to reduce the total maintenance of the bolted connections by about one day".

Different bolt connections on the steel structure require flexibility

Bolted connections of different nominal diameters are installed in the supporting structure of the mountain station. These range from M36-SW55 to M64-SW95 (d 1 1/8”, A/F 2 1/5” to d 2 3/8”, A/F 5 3/8”); the torques to be applied are between 2,800 Nm and 14,762 Nm (2,065 ft*lbs and 10,888 ft*lbs). A total of six different bolt configurations could be controlled with two ITH hydraulic torque wrenches (HTW) and a battery-powered hydraulic unit: 

1.HTW type D-Flex 5 

for torques up to a maximum of 5,000 Nm (3,687 ft*lbs), double-acting hydraulic cylinder, two-hose system.

2.HTW type DKS 250 

torques up to max. 25,000 Nm (18,440 ft*lbs), single-acting hydraulic cylinder, single-hose system.

3.Battery hydraulic power pack ITH Hydro-DAX V18 Battery, 

operating pressure 850 bar, 82 V Li-ion battery, low-wear, brushless 1.5 kW electric motor.

The use of the ITH Hydro-DAX V18 Battery high-pressure hydraulic power unit eliminated the need for time-consuming routing of power supplies. This significantly accelerated the inspection process. The electric drive's load-sense technology continuously adjusts the motor's speed to the load to be applied - which has a positive effect on the battery's charge level.  

Flexible use 

The ITH battery-powered high-pressure hydraulic unit of the type Hydro-DAX V18 Battery could also be used with the different operating principles (single-hose and two-hose system). 

"The development concept of the power unit deliberately included different applications. Hydraulic multi-purpose lifting cylinders can also be operated with the power unit," explains ITH general manager Frank Hohmann, who runs the family-owned business together his brother Jörg Hohmann. "The flexibility and battery operation are a clear advantage for service work on bolted connections. We are pleased that the concept has proven itself and that the customer could realize a significant time reduction."