What is the reason for the foam in the EH tank when the oil filter in the turbine EH oil filter?
[5]: the design of flash vacuum oil filter has a problem, no matter what type of vacuum oil filter machine, its basic principle is in high vacuum environment, according to the different oil flash point, heating evaporation and separation. If the vacuum system design is unreasonable, low vacuum or gas channel are short, will lead to dehydration and incomplete packing layer of water, gas evolution, will fall into the formation of foam oil after filtration, with the final system into the tank. In particular, many of our peers vacuum flash tower using inferior packing or bulk packing, easy to cause the oil retention and partial wall flow (tube wall residual vacuum flash tower), finally fell into the oil bubble.[6]: vacuum vacuum oil filter in operation is too high, resulting in high temperature makes the transition flash, light hydrocarbons, oil additives into the analysis of mixed with oil bubbles, and high degree of vacuum in a large amount of water vapor if it is not timely recovery, or design recovery ability is not good, will cause water vapor and oil interact to form a new bubble.
[2]: steam turbine system design flaws or system aging and other man-made EH steam turbine oil system with steam or water, then will cause the oil emulsion, oil emulsion into the vacuum distillation tower, high temperature vacuum evaporation, will form a bubble, if EH oil vacuum filter without defoaming system or defoaming device damage will lead to the bubble with the oil into the tank to cycle.[3] reason: turbine EH oil has cracked and can not be reused. EH steam turbine oil long-term operation at high temperature, some low molecular groups in the oil additive to volatilize, anti foam agent have disappeared, with the passage of time, oxidation strengthening, oil viscosity increases, the oil film strength also increased, gas permeability variation, provided the conditions for the formation and stability of foam the existence of. Waste oil which can not be reused at this time should be abandoned. In general, the vacuum oil filtration system prolongs the service life of various types of oil in the steam turbine system for 2-3 years, and is not indefinitely extended.
[1]: free gas bubble, general steam turbine lubricating system is generally open or forced circulation type, in a certain degree of exposure in the air, oil churning, mixed with a lot of air, and partly dissolved gas, oil soluble liquid, volume of about 10%. When the vacuum oil filter, vacuum flash tower is vacuum, gas solubility decreased, gas free bubble, but there are some small bubbles exist in the form of oil, with the oil flows in the vacuum oil filter machine, in each link may join the new gas. Finally with the oil movement and arrived in the tank, in the oil phase precipitation, causing bubbles.
Air, it's getting in the air. Change the oil filter, do not use the poor filter.
