Solution of bubble in hydraulic system
When the bubble is produced in the hydraulic system, it must be dealt with in time and reasonable, otherwise it will produce irreparable great loss, which will cause great harm to the equipment. According to our company for many years hydraulic components sales and hydraulic system maintenance experience, Xiaobian summarizes some basic solutions, for everyone based on the actual situation reference.
Bubble formation in the hydraulic system is a persistent disease. So far, the traditional removal methods are still widely used, and there is not much change, and there is no more time effective eradication method.
First, the traditional bubble removal
Understanding of the bubble research and its harmfulness though there are differences, but in the design and manufacture of hydraulic device in the process of considering the problem of removing air bubbles, it is still the only way that removed the bubble by the tank required in the system, in spite of the tank structure to take a variety of measures, such as the horizontal cross-sectional area the oil separator is greater than the depth, and the oil in the oil tank, the residence time of oil inlet and outlet to set farther and larger.
Deficiencies：
However, there are still some deficiencies in the effect of bubble removal and the structure of the device:
According to Stokes's rule, the rising velocity of bubbles is related to the size of bubbles and the viscosity of oil, that is to say, the floating velocity is proportional to the size of bubbles, and inversely proportional to the viscosity of oil. For example, bubbles with a diameter of 0.3mm rise only 30mm every minute in an oil with viscosity of 100 * 10-6m2/s.
Because of the stirring effect of the pump, the bubbles become more and more emulsified at high speed through the valve mouth, and even if they stay in the tank for a long time, it is extremely difficult to float on their own. Therefore, it is very poor to remove the bubbles only by the fuel tank, so it is imperative to research and develop the forced bubble removal device.
The method of natural division of fuel tank is the method of floating to the oil surface and dissolving into the atmosphere by the buoyancy of the bubble itself. The diameter of the bubble is generally 0.25 ~ 0.5mm. If the oil on the bubble interface does not move upward, it will completely depend on its buoyancy to overcome the friction resistance of the oil and move upward.
Hydraulic device structure increased
In addition to the oil tank storage and cooling function, a large volume of a fundamental reason is that taking into account the removal of bubbles, China's fuel tank volume is generally 3~5 times the pump flow, the United States Industry stipulates that the volume of fuel tank shall not be less than 3 times the pump flow. Due to the use of large volume fuel tank, the overall structure of the device tends to become larger and uneconomical.
Two. Forced bubble remover
Forced bubble remover is mainly composed of oil inlet chamber, working chamber, guide impeller, oil outlet and exhaust pipe. When the oil into the oil chamber in the tangent direction, with a certain kinetic energy to guide wheel blades in the guide wheel under the action of liquid spiral acceleration, because the oil quality is greater than the bubble quality, under the action of centrifugal force, the bubble to the center axis of the central axis of the cluster, the pressure is decreasing the increase of liquid flow in the spiral acceleration, minimum diameter at the center of the working chamber pressure is lowest, the bubble in the central axis of the joint effect of pressure difference and close to the central stream to the working chamber movement and minimum diameter point set in the working chamber and the oil chamber with the right near the liquid flow because there is no spiral exercise, so here is higher than the pressure of the oil chamber entrance pressure outside the gas accumulated under pressure through the exhaust device.
