Water Surge Tank

Increasing or decreasing the pressure in pipelines transporting water, oil, etc. in which the fluid is flowing under pressure causes sudden waves which are known as ram shock. The occurrence of the ram impact phenomenon depends on various factors, such as changes in flow rate, pressure and fluid transfer rate. Due to the serious dangers and damages that the phenomenon of ram impact to the body of pipes and fluid transfer facilities creates, by placing a tank surge or shock absorber tank, an attempt is made to eliminate this phenomenon. Surge tank is a metal tank with a very strong body that is installed in the pipelines under pressure in the path of liquid transfer and absorbs part of the fluid by increasing the pressure in the pipe. In other words, it acts as a storage tank by increasing the pipe pressure. In contrast, by reducing the pressure in the pipes too much and preventing the phenomenon of water separation from the column, part of the fluid in the surge tank is transferred into the pipelines and actually acts as a power supply. In the general structure of these tanks, air will be at the top of the tank and water at the bottom. Types of surge tanks According to the pressure in the pipelines and other factors in general, one of the two types of surge tanks can be selected to control and adjust the pressure inside the transmission lines, which are: One-way surge tank One-way surge tank acts as a power supply by being in the path of pipelines. This type of surge tank actually injects part of the fluid that has already been stored in the tank into the fluid transfer path by reducing the pressure in the pipelines. This prevents the phenomenon of fluid separation from the column and the impact of the ram, which eventually leads to cracks in the pipes and installations. This tank is installed above the level of the transmission lines and its maintenance cost is relatively high due to its long distance to the pumping station. Two-Way Surge tank As the name implies, this type of surge tank can play the role of power supply and storage due to the conditions inside the transmission pipes. In other words, by increasing the pressure in the transmission lines and in order to prevent the occurrence of rams, part of the fluid is transferred into the tank. As the line pressure decreases, it will act as a one-way type and part of the fluid in the tank will be injected into the pipeline. As fluid enters or leaves the tank or pipeline, the internal air in the tank will contract and expand, and the effect of increasing or decreasing the pressure will be reasonably reduced. In another category and according to the method of installation of these tanks, they can be divided into groups: Free standing surge tank, horizontal and oblique surge tank. As is clear from the name of each group, in the standing type, the tank is installed vertically in the path of water or oil transmission lines, and due to its strengths, it is used more than the other two types. The oblique type of these tanks has limitations in terms of how to fix it and prevent movement and shaking, and finally in horizontal surge tanks we will face the problem and limitation of increasing the volume of space without using water. Of course, it should be noted that according to the environmental conditions in which the tank is installed and the positive and negative characteristics of each type of tank, the appropriate option is selected.