The Simulation On The Automatic-flushing Scheme Of The Huge AGC Cylinder

In modern metallurgical industry, with the precision of hydraulic AGC control system widely used, in which the hydraulic system of the harm caused by pollution are also increasingly been recognized and valued. Pollution not only enables the performance deterioration of hydraulic components, reduce effective life or even be able to make the system to a standstill. AGC system uses servo-valve as input signal converter and amplifier for oil cleanliness requirements higher, so the oil pollution controlling needs to be a high priority. Contaminants in the system generation process. Cylinder as the AGC system hydraulic actuator, its frequency response is high, the load to bear large, so contaminant is generated in the process of the relative movement due to the long prone to frequent shedding. These pollutants will have a greater impact to the servo-valve while the piston return. Therefore the motion of solid particles and servo-cylinder internal flushing scheme is important to improve the performance of servo system’s role.This thesis take the rod less cavity of AGC cylinder as the study subject. At first we use the theory of hydraulic transport to analyze the movement of the solid particles on the bottom of the cylinder. Then calculate all kinds of different size particles in the cylinder at the bottom of the stacking velocity and the oil speed which is able to make solid particles to deposit velocity (the oil speed before momentum transfer). Then using the computational fluid dynamics theory to calculate the velocity distribution at the bottom of the cylinder, at the same time according to the calculated momentum before the exchange rate of the hydraulic oil to determine the effect of washing solution. At last, because the cylinder is remoulded for the design of the flushing, so we need to analyze it using finite element thesis to make sure this transformation does or not affect the strength of the cylinder.The results shows that:when the oil’s velocity at the bottom of the cylinder reaches or exceeds a certain speed, it could make the solid particles reach or exceed the accumulation rate through the exchange of momentum. So the solid particles could be able to start moving in the bottom of the cylinder. And the flushing pump station flow size, the viscosity and the piston servo cylinder rod in the process of flushing the location factors have great influence to the flushing effect. Compared to the effect of this method, the method of using the pressure pulse flushing flow has a greater improvement. The strength of the cylinder which has remoulded has no obvious influence compared to the one before, so the irrigation scheme is feasible.