As a key device to ensure the safety of hydrogen system, the rated pressure and displacement parameters of hydrogen safety valve are crucial. These two parameters are directly related to whether the safety valve can effectively play a safety protection role when the hydrogen system is abnormal, ensuring the safe and stable operation of the system.
The rated pressure is the set pressure value for the hydrogen safety valve to open and release pressure. When the pressure in the hydrogen system exceeds the rated pressure, the safety valve will automatically open and discharge the hydrogen in the system to prevent safety accidents such as explosion caused by excessive system pressure. If the rated pressure is set too low, the safety valve may open frequently when the pressure fluctuates during normal operation of the system, resulting in unnecessary leakage of hydrogen, affecting the normal operation of the system and increasing safety risks. On the contrary, if the rated pressure is set too high, when the system pressure is already in a dangerous state but has not yet reached the rated pressure, the safety valve cannot open and release pressure in time, and the system will be subject to overpressure risk, which may lead to serious consequences such as pipeline rupture and equipment damage.
The displacement parameter determines the amount of hydrogen that the safety valve can discharge per unit time. When a failure in the hydrogen system causes a sharp rise in pressure, the safety valve needs to quickly discharge a large amount of hydrogen to reduce the system pressure. If the displacement parameter is too small, the safety valve cannot discharge the excess hydrogen in the system within the specified time, and the system pressure will be difficult to be effectively controlled. It may continue to rise and exceed the system's tolerance limit, thus causing a safety accident. If the displacement parameter is too large, although it can quickly release pressure, it may cause excessive hydrogen discharge, which not only wastes resources, but also may cause other safety problems during the discharge process, such as hydrogen accumulation to form a combustible mixture.
The rated pressure and displacement parameters are interrelated and synergistic. The appropriate rated pressure setting is the premise to ensure that the safety valve can respond to the system overpressure in time, and the matching displacement parameter is the key to ensure that the safety valve can effectively control the pressure rise. For example, for a hydrogen system with a specific volume and operating pressure range, the appropriate rated pressure must first be determined according to the system's design pressure and safety requirements, and then the required safety valve displacement parameters must be calculated based on the system's possible maximum pressure rise rate and the allowable pressure fluctuation range to ensure that after the safety valve is opened, the system pressure can be reduced to a safe range within the specified time.
In different hydrogen application scenarios, the requirements for the rated pressure and displacement parameters of the hydrogen safety valve are also different. For example, in hydrogen refueling stations, due to the high pressure of hydrogen storage and filling and the large hydrogen flow rate, it is necessary to equip safety valves with high rated pressure and large displacement to cope with possible high-pressure and large-flow hydrogen leakage. In some small hydrogen experimental devices, the system pressure and flow rate are relatively low, and the rated pressure and displacement requirements of the safety valve are relatively small. If the parameters are not reasonably selected according to the specific application scenario, the safety valve may not meet the safety protection requirements.
In actual applications, safety accidents caused by improper selection of hydrogen safety valve rated pressure and displacement parameters have occurred. For example, after the expansion of a hydrogen production enterprise, the safety valve parameters in the new system were not recalculated and adjusted, and the safety valve of the old system was still used. As a result, when the system pressure suddenly increased due to an equipment failure, the safety valve failed to open in time due to the high rated pressure, and the displacement could not meet the demand for rapid pressure relief, which eventually led to the rupture of the hydrogen storage tank, causing a serious explosion accident, resulting in huge casualties and property losses.
The rated pressure and displacement parameters of the hydrogen safety valve have a crucial impact on its safety protection effect. When designing, selecting and using a hydrogen safety valve, it is necessary to fully consider the system's working pressure, flow, volume and other factors, reasonably determine the rated pressure and displacement parameters, and ensure that the two match each other, so as to achieve the best safety protection effect of the safety valve in the hydrogen system and ensure the safe and stable operation of the hydrogen system.
