A storage tank is a sealed container used to store liquids or gases, widely used in industries such as petroleum, chemical, food, and pharmaceuticals. Its working principle is mainly based on four core mechanisms: sealed storage, pressure balance, heat transfer, and liquid level measurement. Through a rationally designed structure and operating mechanism, the safety and stability of the stored substances are ensured.
Sealed Storage Principle: The storage tank forms an independent space isolated from the external environment through sealing gaskets at the top and bottom, as well as sealing devices at manholes and connecting pipes. This sealed design effectively prevents the stored substances from contacting air, moisture, and impurities, thereby ensuring the quality and stability of the materials. For volatile liquids, good sealing reduces evaporation loss, minimizes material loss, and prevents volatile gases from polluting the environment.
Pressure Balance Principle: The pressure inside the storage tank changes due to variations in the temperature and volume of the stored substance, as well as external environmental factors. By installing pressure balancing devices such as breather valves or safety valves, when the internal pressure rises above a set value, the breather valve automatically opens to release some gas, reducing the pressure. When the pressure drops to a certain level, the breather valve automatically closes to prevent outside air from entering the storage tank, thus maintaining a relatively stable internal pressure. This pressure balancing mechanism prevents damage to the storage tank caused by excessively high or low pressure, ensuring its safe operation.
Heat Transfer Principle: Storage tanks have a certain thermal conductivity. Heat is transferred between the inside and outside of the tank through conduction, convection, and radiation. When the external ambient temperature changes, heat is transferred to the stored substance through the tank wall, and vice versa. Based on this principle, for tanks storing high-temperature liquids, insulation measures are needed to reduce heat loss; for substances requiring cooling, external cooling media can be used to exchange heat through the tank wall, lowering the internal temperature to meet the temperature requirements of the stored substance.
Level Measurement Principle: To accurately determine the liquid level in the storage tank, buoyancy-based, pressure-based, and ultrasonic level measurement methods are commonly used. Buoyancy level gauges measure liquid level by utilizing the principle that the buoyancy of a float in a liquid changes with the liquid level; pressure level gauges calculate the liquid level by measuring the pressure at the bottom of the liquid; and ultrasonic level gauges measure liquid level by emitting and receiving ultrasonic signals. These level measuring devices can monitor the amount of material stored in storage tanks in real time, providing a basis for production management and preventing overflows or emptying.