Steel Constructions

Apart from the standard trash rake programme Heidemann Wasserkraftanlagen carries out design and production of exceptional constructions.
For example, sometimes environmental regulations prescribe that certain parts of the hydropower plant are to be invisible when in operation. It also can happen, that whilest the power plant is under construction, it turns out that additional equipment is required which should be delivered in a reasonable time span. One of many examples is the canal draingate for a 1.5 MW powerplant, shown on the following pictures:

Environmental regulations enforced that no part of the gate drive had to stand out from the brim when the powerplant was in operation. Since the operation water level is even with the brim this meant that a special submersible gate drive had to be designed. In this case the experience in vehicle construction was extremely handy, the whole gate drive system is designed similar to the rear axle of a Unimog 4 WD. The two deck centre gearbox contains a primary worm gear and a secondary spur gear drive that distributes the power to both sides.

The two winches contain another reduction drive. The power comes from a hydraulic unit which is installed in a pit in the canal wall. and is transmitted via hoses to a hydraulic motor which is flanged onto the centre gearbox. The whole draingate is designed as roller gate with flat rubber sealings on all four surfaces. To prevent water leaking, into the gearbox the whole system is filled with a biodegradable ester oil which is also the pressure oil for the power transmission.

The leak oil from the hydraulic motor is not straight away returned to the reservoir of the hydraulic unit but is detoured into the gearbox system. From there only, the return hose feeds surplus oil back into a small indication tank and from there back into the reservoir. This tank is installed with an elevation difference of 2.5 m above the gearbox, so that there is an over pressure of approx. 0.2 bar. In the event of a leak water does not infiltrate the system but in worst case oil starts to escape.
Roller gate under construction, H=1,5 m Width = 5 m, water level above = 5,4 m, coarse grid, H = 3 m width = 10 m, on left hand side
Roller gate under construction, H=1,5 m Width = 5 m, water level above = 5,4 m, coarse grid, H = 3 m width = 10 m, on left hand side

Two part canal inlet gate H = 6 m, Width = 10 m, under construction, stationary part insalled, mobile gate and drive gear yet to be installed
Two part canal inlet gate H = 6 m, Width = 10 m, under construction, stationary part insalled, mobile gate and drive gear yet to be installed