Anyone who lives or works along a body of water knows that flooding is always a concern. In the North/Baltic Sea region, the city region of Greifswald and the urban district of Greifswald-Wieck in Germany know this all too well. Due to its exposed location, this region is one of the most vulnerable in the area. So, this summer, the first steps were taken to protect this area from storm surges with the construction of a flood barrier in Griefswald. This barrier utilizes Pfaff-silberblau brand SHE worm gear screw jacks, manufactured by Columbus McKinnon Engineered Products in Germany, to move the sliding gates of the harbor pier into place to protect against flood waters.
The new flood barrier in Greifswald is part of what is currently the largest coastal protection project in Mecklenburg-Western Pomerania. If a flood warning is issued, the main gate of the flood barrier is locked with the aid of a revolving segment to protect against high tide. At the same time, sliding gates that are approximately 55.7 ft (17 meters) wide and weigh 19.8 tons (18 metric tons) are closed on the south and north pier of the flood barrier. These gates run on railway tracks similar in principle to an oversized sliding door. This is precisely where the worm gear screw jacks from Pfaff-silberblau come in.
In the event of an emergency, and also for maintenance purposes, each sliding gate has to be lifted from its parked position in the sliding gate chambers of the dam. This is done using a rocker with travel wheel to lift the gate up to 5.9 inches (150 millimeters) and then safely lower it onto the rail. The wheel is lifted at a speed of 1.96 inches (0.05 meters) per minute by means of an electromechanical drive unit designed specifically for this application by Pfaff-silberblau.
This drive unit consists of a 25 Series worm gear screw jack with a rotating and self-locking trapezoidal screw, special travelling nut, absolute encoder, special grease and a bevel gear box motor with 2 hp (1.5 kW) actuating power. In case of an emergency, the drive unit also features a hand wheel at the motor.
When designing the drive unit, the team also took special care to ensure the harsh conditions of this outdoor maritime application would not affect its functionality. The screw jack has a special flexible protection boot. All other driving elements are made of weatherproof materials and are protected with special high-quality paint. The electrical components are designed in compliance with protection class IP66. Because of these features, the drive solution from Pfaff-silberblau can also withstand outdoor use in temperatures ranging from -4°F to +122°F (-20°C to +50°C.)
This is a great example demonstrating how Columbus McKinnon Engineered Products designs special systems to meet tough and challenging customer applications.