Working principle of oil separator
In the centrifugal force field, the centrifugal force increases with the increase of material density. The working principle of the oil separator is: when the fuel containing impurities is continuously supplied into the high-speed rotation of the separation cylinder and with the separation cylinder for high-speed rotation, under the action of centrifugal force, because of the different density of the liquid into the separation cylinder, it will be re-stratified distribution. The density of water droplets and mechanical impurities is larger, and the centrifugal force is larger, which is thrown to the periphery under the action of larger centrifugal force. The water is led out from the drainage port, and the impurities are removed regularly through the slag discharge port. The density of oil is smaller and the centrifugal force is smaller, so the oil will flow inward and gather near the internal shaft, flow out of the upper oil outlet, and get the purified oil. In a rapidly rotating cylinder, the fuel containing the impurities will be subjected to a centrifugal force thousands of times or more than the force of gravity. The oil separator uses the principle of centrifugal separation to purify the fuel containing impurities, which can shorten the purification time. At the same time, because the purification process is cyclic and large amount of separation, the purification efficiency of dirty oil is high.
Factor analysis of oil running fault of oil separator
According to the working principle of oil purifier and the actual work process, oil purifier run oil fault is caused by poor water seal, and many factors influencing the water seal water, in which any one or more of the following factors are likely to make oil purifier can't be able to establish a water seal or maintain water seal, the area designated for oil water interface migration phenomenon is due to run oil eventually lead to the water seal was damaged.
1. Improper selection of specific gravity ring
Because the inner diameter of the specific gravity ring determines the location of the oil-water interface of the oil separator, the location of the oil-water interface of the oil separator is directly affected by the size of the inner diameter of the specific gravity ring, and the size of the inner diameter of the specific gravity ring is determined according to the density of each different fuel. If the oil separator is the use of high density fuel, the selected specific gravity ring diameter should be relatively small, and if the selected specific gravity ring diameter is larger than the actual, the oil and water interface will be offset and outward, resulting in fuel from the outlet run out; On the contrary, if the inner diameter of the specific gravity ring is too small than the actual size, the oil/water interface will shift and move inward, resulting in unclean separated fuel.
2.There is no water in the high water tank or the water distribution system is blocked
If there is no water to support the movable chassis of the oil distributor, the water seal flow introduced will run away from the slagging mouth and will not form a water seal. If there is no water seal, the fuel entering the separator will not be separated, but will run away directly from the slag discharge mouth, resulting in fuel waste. Because there is no pressure at the oil-water interface, the oil is thrown out of the separator by centrifugal force instead of flowing out of the outlet. If there is no water in the high water tank, or the scale of the water distribution system is blocked, and part of the pipeline or valve of the water distribution system is dirty and blocked, the water can not be introduced into the separation cylinder, and the water seal can not be established, resulting in the slag discharge mouth running oil.
3.Leakage of working water
The pressure drop of working water is due to the oil separator leakage and compensation loss of balance, and the direct cause of the imbalance is a large number of leakage of working water and compensation water supply speed is too small, and finally lead to the sliding chassis of the oil separator is difficult to be lifted, causing a large number of leakage of water sealing water, resulting in the accident of fuel discharge directly from the slag mouth.
(1) If the working water seal ring of the oil separator cannot be effectively sealed, a large number of leakage of working water will occur.
(2) If the throttle hole on the main body of the separation cylinder is blocked, the plastic plug seal on the sliding ring is not strict and the spring can not be reset, the movable chassis can not be sealed with the separation cylinder cover, so as to affect the establishment of water seal water, resulting in the oil separator running accident.
4.The speed of internal separation cylinder is too low
If the friction plate is damaged and skidded, the separation cylinder body does not have enough speed, that is to say, the separation cylinder body cannot produce enough centrifugal force, then the oil and water interface moves outward, causing the water outlet to run oil. Therefore, before sealing, water sealing and oil separation, the motor must be used to drive the oil separator, so that the oil function reaches the rated speed, so that the oil separation process of the oil separator will not run oil phenomenon.
5.Separate the dirty and blocked disk
In the whole ship, every part of the ship is very important, and the oil separator as a part of the ship, so that each important part of the oil separator should be cleaned and maintained regularly, especially the separation plate should be cleaned regularly to separate the impurities on the plate, so as to keep it clean. The significant increase of fuel pressure of separator separator plate is due to the serious dirty blocking of separator plate, which leads to the fuel will not be evenly distributed to each separator plate, so that the oil-water interface will shift outward, and the phenomenon of separator outlet running oil occurs.
6.The oil temperature is too high or too low
(1) The oil temperature is too high. When the temperature of the fuel containing impurities into the oil separator is too high, it will evaporate because of the high temperature, resulting in a large reduction of water seal, so that the water seal will be broken, resulting in the oil-water boundary outward offset, and the oil separator outlet will run.
(2) The oil temperature is too low. In the formula, is the diameter of the oil outlet, is the diameter of the water outlet, namely the inner diameter of the gravity ring, is the diameter of the oil and water interface, and is the ratio of the density of water and oil corresponding to the separation temperature. It can be known from the above formula that the position of oil and water interface is related to temperature and the density of oil and water. If the temperature of the fuel containing impurities into the oil separator is too low, it will cause the oil-water boundary outward offset, and eventually make the water outlet of the oil separator run oil.
7.Improper Operation
In the establishment of water seal water, when opening the fuel inlet valve, if the speed of opening the valve is too fast, the amount of oil is too large, resulting in impact damage to the water seal, so that the fuel runs out of the water outlet.
8.The discharging process of the discharging oil pump is abnormal or the fuel outlet valve is not opened
The discharge pump of oil separator is a non-rotating centripetal pump. The main reason why the centripetal pump can not discharge oil normally is that the centripetal pump is seriously dirty and blocked. If the centripetal pump is seriously dirty and blocked, the fuel can not be discharged, the oil pressure in the separation cylinder is increased, the pressure of the fuel surface on the oil-water interface is greater than the pressure of the water seal surface, causing the oil-water boundary to outward offset, and finally making the oil separator's outlet run oil phenomenon.
9.Net oil flow is blocked
The height of the vertical shaft is too low to prevent the flow of net oil, which makes the net oil into the water chamber and causes the outflow of oil.
10.Poor sealing
If the main sealing ring between the separation cylinder cover of the oil separator and the movable chassis is not pressed or has been damaged, resulting in poor sealing, water leakage will occur, and oil running phenomenon will also occur at the outlet of the oil separator.
As can be seen from the above analysis, all of the above factors may lead to faults, but the faults caused by them are different. We should analyze the oil running fault of oil separator concretely and find out the real cause of the accident from the phenomenon.
