Design And Key Technology Research On High Pressure Pneumatic Blowing Valve With Differential Pressure Control

Emergency buoyancy system is an important guarantee to submarine’s safety, in order to improve the self-help ability of submarine in a crisis situation, an extra-high pressure pneumatic blowing valve with differential pressure control is developed. Compared with the traditional technique of artificial control emergency blowing, using the blowing valve to emergency blowing not only has the advantages of high efficiency, high reliability and easy to realize automatic control, but also can effectively control the external seawater and the main ballast tank seawater pressure difference within a certain range. It prevents the ballast tank from being blown broken, which makes the submarine in more dangerous situation. Because the blowing valve is mainly used in national defense industry, the study about it is nearly not reported at domestic and fyerseas, the research on it is still in the initial stage in our country. In this paper, the exploratory research is conducted on the blowing valve, and it have already achieved a certain amount of research results. The successfully development of the blowing valve is of great significance for the improvement of China’s submarine safety performance. The main contents of this dissertation are as follows.1.This paper summarized the domestic research status about submarine emergency blowing technology and introduced a emergency blowing technology which is adopted on blowing valve. An extra-high pressure pneumatic blowing valve with differential pressure control is developed, and its working principle and working process are introduced in detail. Finally, the technical indexes and its key technology are introduced.2. It analyzed the two-stage throttling characteristics of blowing valve, considering that the main valve core orifice diameter is more difficult to precise calculation in theory, the replaceable throttling bolt is designed on the main valve core to adjust the diameter of the orifice. The main valve core is designed to be a trapezium, and a limit surface is designed between the main valve core and the valve seat contact interface. They can make the seal ring hardly afford air pressure and air scour, and it can prevent the sealing ring from being excessive compressed and improve the service life of sealing ring.3. Two work modes of vice valve are introduced. For the performance of vice valve port seal the paper designs two kinds of structure, including cone valve hard seal and sealing ring soft seal. Through the analysis of the advantages and disadvantages of two kinds of sealing way, It finally chooses the way of using sealing ring soft seal.4. The working principle of the control valve is analyzed. Considering the characteristics of small deformation resistance and large bearing capacity on rubber diaphragm, the rubber diaphragm is chosen. The pressure plate are set up on both surfaces of the rubber diaphragm, which can improve the bearing capacity of rubber diaphragm. The glyd ring is used in control valve stem seals and appropriately increases its diameter of diaphragm, which effectively improves the sensitivity of the control valve.5. The paper analyzed the performance of the blowing valve’s opening and closing characteristic, the flow time of the main valve cavity on the core and its gas displacement. The strength of the blowing valve body was calculated, and the result show that the strength can meet the design demands. At last, according to analysis on the strength of valve body by ANSYS, it can draw the conclusion that the body’s stress is uniform, the maximum stress is far less than the yield limit of material and the body’s safety performance is good.6. According to the physical model of the blowing valve, the paper set up its simulation model by AMESim, and had a research on its dynamic characteristic of the system according to the actual working condition.The conclusions are as follows:the blowing valve performance is stable, the response is sensitive and the precision of differential pressure control is high. Also, the air pressure, outside seawater pressure and water ballast tank volume has no effect on differential pressure control performance of the blowing valve. But increasing the air pressure, reducing the outside seawater pressure and the water ballast tank volume can effectively improve the efficiency. Changing bore diameter of the throttle valve core and the amount of precompression in control valve spring can adjust the control range of the blowing valve differential pressure.7. The blowing valve experiment system is established, which is aimed to carry on the experimental research on the safety performance, high pressure sealing performance and functional performance of blowing valve. The problems that are exposed in the process of experiment are analyzed and corrected. The conclusions are as follows:the blowing valve’s strength can meets the design requirements and the safety performance is good. Its main valve and vice valve sealing performance are good under the condition of shut state. The sealing way is feasible and reliable. Vice valve opening pressure increases with the pressure of high pressure gas cylinders. Valve action changes only with the main ballast water tank and tank external water pressure, and there is no direct link with high pressure gas cylinder pressure. Changing the main valve throttle valve core hole diameter and the amount of control valve spring precompression can adjust the control range of blowing valve differential pressure. The experimental results are consistent with AMESim simulation results.Finally, the blowing valve research work is summarized, and the shortcomings in the process of development and the follow-up work are prospected.