Surge tank
A surge tank is a large vertical reservoir that is strategically placed in pipeline systems, particularly near turbines, to manage excess water and regulate pressure. Typically constructed from steel or reinforced concrete and often partially buried underground, surge tanks play a critical role in protecting pipeline integrity. They function by absorbing fluctuations in water pressure; when pressure drops, water flows into the tank, and when pressure rises, the tank releases water to prevent overflow. The design usually includes an open top to accommodate potential overflow, with some tanks reaching significant heights to handle large volumes. Surge tanks also incorporate features such as electric heaters in colder climates to prevent water from freezing, which can lead to pipeline failures. They come in various forms, including simple surge tanks and more complex gallery surge tanks with multiple storage chambers. Overall, surge tanks are essential for maintaining the stability and efficiency of water systems, providing safety and reliability in hydraulic operations.
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Surge tank
Surge tanks are large tanks that serve as a reservoir for excess water near a turbine in a pipeline. In most cases, they are constructed of steel or concrete and built partially underground. The top of the tank is normally left open in case of overflow. Surge tanks help regulate pressure in a pipeline by adding water if the pressure drops too low or removing water when the pressure becomes too high. This helps prevent damage to the pipeline.
Overview
Surge tanks are large vertical tanks connected to pipelines that are sealed with a valve. When the valve is closed, water that would normally pass through the opening must find an alternative path. This causes the water to flow into the surge tank, which makes the water level within the tank rise. The bottom of the surge tank is kept below the water reservoir level, stopping any air from flowing into the pipe system. For this reason, surge tanks are often built partially underground.
The top of most surge tanks is usually left open because the bottom of the tank, which is partially underground, keeps it full of water. Open-topped surge tanks are often built taller than necessary to keep them from overflowing in a stressful situation. Some surge tanks are built hundreds of feet tall to account for large amounts of excess water. However, in some locations, surge tanks can be allowed to occasionally overflow without resulting in damage to the tank, pipeline, or surrounding area.
Surge tanks with portions above the ground are often built from steel or reinforced concrete. These materials are strong enough to handle the immense weight and pressure of large amounts of water and are also cost-effective. If a surge chamber is built completely underground, it is possible to excavate the chamber directly into the rock. This eliminates the need to build a structure above ground. However, this can only be attempted in geographic areas with large amounts of rock in the earth.
Colder climates sometimes pose problems for surge tanks and similar structures. Large, open reservoirs of water directly connected to expensive, difficult-to-repair pipelines can sometimes freeze. This can cause the pipeline to burst, leading to extensive, costly repairs. To combat this, engineers incorporate electric heaters into the surge tank. These heaters stop the water from freezing, preventing damage during colder seasons.
In most cases, surge tanks serve three important functions in a water network. They protect the system from high internal pressure, which can severely damage the pipe network, by providing an outlet for excessive water. They can help regulate the amount of water entering a hydraulic turbine by regulating the water pressure surrounding the turbine. Finally, they serve as a reservoir of excess water for situations in which water pressure in the system would otherwise drop too low.
Surge tanks come in a variety of types. Simple surge tanks are constructed with a vertical pipe branching off from a pipeline near a turbine. The pipe opens to a large tank. Gallery surge tanks are similar, except they contain a number of chambers in which water can be stored.
Bibliography
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