Vietnam is a country with a hot and humid tropical climate and the highest density of thunderstorms in the world. When lightning strikes over voltage, it will cause problems on the power grid system. Therefore, the lightning protection valve is an indispensable safety protection device for the power grid.
Van chống sét là một trong những cơ cấu không thể thiếu trên mỗi thiết bị áp lực. Vì là một phần của hệ thống chống sét nên việc chọn lựa van chống sét an toàn cũng là một vấn đề khá quan trọng; để chọn được van an toàn, cần chú ý các điều sau:
a/ Keep the following parameters in mind:
– MCOV (Maximum continuous operating voltage): The maximum continuous operating voltage applied to the lightning protection device
– TOV (Temporary Overvoltages): The arrester may be subjected to a transient overvoltage.
– Energy: the lightning protection device's ability to dissipate energy.
b/ Check carefully before putting the device into operation.
c/ During the operation of the equipment, maintenance is required according to regulations.
d/ Inspect equipment periodically or when an abnormality occurs; Safety valve inspection includes the following basic steps:
– Visually check the technical condition of the valve.
– Use gas (compressed air, nitrogen) or liquid (water, specialized oil) to increase pressure to check the operating pressure and the closing pressure of the valve.
– Check valve tightness; Surge protection valves are divided into 2 types, suitable for different options
– Type 1 is for power distribution stations.
– Type 2 for intermediate power stations
e/ In addition, the lightning protection valve must work normally under the following conditions:
– The temperature of the environment where the magnetic lightning valve is installed and used is minus 10oC đến 40oC
– The height of the place where the lightning protection valve is used must not exceed 1000 m above sea level.
– The power frequency voltage to earth, at the place where lightning protection valve is used, is not allowed to be greater than the maximum allowable voltage of the lightning protection valve.
– The lightning protection valve must have an explosion-proof structure to protect the valve from exploding when the pressure inside the valve exceeds the allowable pressure.
– The lightning protection valve must be airtight to prevent moisture and water from entering.
– Metal parts of lightning arresters must be protected against atmospheric corrosion
– The lightning protection valve must have enough parts for assembly and connection to ensure the fixing of the lightning protection valve when installing and using it, and ensure good electrical contact and grounding.
– Lightning protection valves must be packed and fixed firmly to ensure that the valve is not damaged during transportation. If the packaging is more carefully designed, it can clearly state the type of fragile product or draw signs to preserve fragile goods.
– Lightning protection valve must have a certificate and the technical documents of the valve must clearly state the technical parameters of the valve, the valve preservation mode.
Carrying out the steps to test the safety valve requires specialized equipment and a team of well-trained technicians and specialists to ensure the lightning protection system works best in these conditions. severe weather.