A high-head flat counterbalanced gate

Conclusions

• 1. In order to increase the capacity of high-head water intakes substantially, it is necessary to develop basically new designs for the gates, providing not only for a decrease in frictional forces in the bearing-guide sections, and, in tum, a reduction in the lifting capacity of the mechanisms, but also a reduction in the loads on the bearing-guide sections.

• 2. The gate design provides for uniform transfer of the heavy loads received by the gate (of the order of 15,000 tons) onto a large concrete surface. Hydraulic hoists, which have been perfected by industry, are available for maneuvering the gates.

• 3. Owing to use of a moving structure that operates as a beam on two supports with cantilevers, similar types of gates can be used to close water intakes with even significantly larger cross sections than those designed for the Rogun hydroelectric plant.

• 4. Model studies of the operation of back-pressure chambers indicated that reliable gate counterbalance is provided for even with complete failure of the chamber seals.

• 5. As studies indicated, bearing-plate deflectors attached to the basic gate protect the supporting bulkheads under no-head conditions in the outlet section: a flow coursing from beneath the gate has no effect on the lateral surfaces of the bulkheads.

• 6. The gate is constructed from common grades of steel used at the present time and can be completely fabricated at the plants operated by the Gidromontazh Trust. The gate has no heavy inserted parts fabricated from high-alloy steels.

• 7. Data from studies conducted on the flat counterbalanced gate and gate chamber indicate that this gate can be applied to deep water intakes at high-head hydrofacilities.