In the process of tanker transportation, static electricity as an “invisible flame”, sometimes an inattentive, will cause unexpected dangerous accidents. So, how to prevent static damage?
The amount of oil in the tank should be appropriate
The oil tank of the tank is too little, and the shaking space in transportation is large, which is easy to produce static electricity; If it is too much, it is easy to overflow the car whose tank mouth is not tightly sealed, so the filling amount is appropriate at about 85%. In addition, the medium speed should be maintained during transportation to ensure that the oil in the tank is relatively stable, and emergency braking should be minimized.
When changing the oil loading, the original oil should be drained
The so-called change of filling of oil means that, for example, oil tanks that used to contain gasoline are now filled with kerosene or diesel or vice versa. Changing the oil loading is easy to form an explosive mixture of gases in the tank, especially when the oil tank of the oil tanker is originally filled with gasoline, and now it is filled with kerosene or diesel. The reason is that because kerosene and diesel have the nature of absorbing gasoline steam, it will make the oil tank that has been filled with gasoline steam and reached the oil-rich state, is diluted to the range of explosion, especially in winter, if the electrostatic fire occurs, that may occur fire, explosion and other serious accidents.
According to an accident investigation report by the American Petroleum Institute, in 620 cases of static electricity accidents in tank cars, 440 cases are caused by changing the oil loading. Therefore, when the tank car changes the filling of oil, it is necessary to exhaust the deposited oil in the tank as far as possible, open the mouth of the oil tank, and let the oil remaining in the tank volatilize as much as possible. In addition, when filling oil, the oil personnel should also be told about the original oil in the tank, so that the oil personnel can operate according to the regulations, such as limiting the flow rate of oil delivery.
Keep tanker tanks clean
The tank can not contain moisture, impurities, etc., because the water in the fuel will significantly change the charging trend of the fuel, so that the voltage in the tank into tens of times, or even hundreds of times, while it may also be discharged in the form of sparks.
Impurities in the oil also have a greater impact on the generation of static electricity, especially some floating substances, such as wood chips, rubber, isolated metal balls (some tank tank content meter float off) is very dangerous. Mainly, this kind of conduction has a capacitive effect to collect and store more electrostatic charges, and there is no fixed movement track in the tank tank, which is easy to approach the tank wall or other accessories in the tank tank, and form an appropriate discharge gap. According to the test, once this phenomenon is formed, as long as the potential difference with the liquid level is 1-2KV, spark discharge may be generated (the ordinary liquid level is 28-30KV), and the discharge energy is strong, and all the stored energy can be released at one time.
Keep all other accessories in good condition
For the valve on the tank, the exhalation valve, the tank cover sealing ring of the tank car, etc., should always be in good condition to prevent the leakage or overflow of fuel, and the fire in case of electrostatic fire.
Connect the electrostatic wires
Before loading and unloading the oil, the oil tanker and the oil loading and unloading equipment should be connected together with electrostatic wires (the oil depot is equipped with electrostatic wires that are connected with the oil tanker).
Functions:
① the electrostatic conductivity induced by the oil tank is carried away to avoid flaring with external substances;
(2) Make the tank car and the entire loading and unloading equipment maintain equal potential to prevent potential difference;
③ It has the effect of accelerating the leakage of electric charge in oil. When connecting electrostatic wires, it is necessary to choose the non-corroded and exposed metal parts on the tank car, and it can not be connected in the place of serious rust or paint.
The data show that only when the resistance of the whole electrostatic grounding system is less than 10 ohms, can the good electrostatic conductivity be achieved. The more ideal way is to install a special copper connector at a certain part of the tank car for connecting electrostatic wires. In addition, the electrostatic grounding wire on the tank truck can not be used as the electrostatic conductor for loading and unloading oil, because the tank car in the loading and unloading of oil, generally parked on the cement floor or relatively hard ground, the electrostatic grounding wire resistance can not be less than 10 euros, therefore, it is difficult to ensure that the same loading and unloading equipment to maintain equal potential.
Ensure that the anti-static equipment on the tanker is in good condition
The antistatic facilities on the tank car are mainly electrostatic ground wires and oil traps in the tank. There are two kinds of electrostatic ground cable: chain type and conductive rubber bracket. The former due to the mopping impact is easy to produce sparks, grounding is at intervals, coupled with easy rust will increase leakage resistance and other shortcomings, now the new factory tank cars are using rubber ground. Therefore, the electrostatic ground cable should be adjusted frequently to ensure that it has good contact with the ground and should be used to check whether the multimeter is smooth, there is no break, and replace the problem in time. The function of the oil baffle is to reduce the shaking and splashing of the oil in the tank during the transportation of the oil tanker to reduce the static electricity generation. If the grease trap is removed from the maintenance tank, it should be installed in time and must not be considered as an optional device.
