火箭推进

静环是端面密封的主要组成部分,石墨环热压环节是整个静环生产的核心,热压成品率直接关系端面密封的质量可靠性。结合生产工艺过程,深入分析了热压工艺机理,建立了静环热压的数学模型,明确了镶嵌应力、过盈量校核等一系列参数。在此基础上,形成了一套完备的热压工艺方法。结合某型号试车端面密封故障问题,对静环进行了仿真分析和试验验证。结果表明,在热反浸过程端面密封受到高温作用,由于石墨材料线性膨胀系数发生变化,导致石墨环和静环座间的过盈量减小,过盈连接部位局部存在微缝隙,石墨环受高压介质挤压不均匀脱出,石墨环脱出不均匀导致石墨端面变形,产生泄漏。

Static ring is the main component of the face seal, the hot pressing of graphite ring is the core of the static ring production, the yield is directly related to the quality reliability.Based on the production process, the mechanism of hot pressing process was deeply analyzed, and the mathematical model of static ring hot pressing was established, and a series of parameter, such as the mosaic stress, the amount of interference were defined.On this basis, a complete set of hot pressing process was formed.The simulation analysis and experimental verification of the static ring were carried out based on the seal failure of a certain type of tests.Results show that in the process of hot dipping high temperature effect of face seal, the interference between graphite ring and static ring seat decreases due to the change of linear expansion coefficient of graphite material, then there are some gaps in the interference junction, graphite ring by high-pressure uneven extrusion, which leads to deformation of the graphite ring face and results in leakage.

引言
1 机理分析及数学模型
2 热压工艺
3 故障分析
4 结论

图1 镶嵌式静环示意图<br/>Fig.1 Mosaic static ring schematic diagram

图1 镶嵌式静环示意图
Fig.1 Mosaic static ring schematic diagram

图2 过盈镶嵌示意图<br/>Fig.2 Interference mosaic diagram

图2 过盈镶嵌示意图
Fig.2 Interference mosaic diagram

图3 静环座的应力计算模型<br/>Fig.3 Stress calculation model of static ring seat

图3 静环座的应力计算模型
Fig.3 Stress calculation model of static ring seat

图4 静环座应力图(内压)<br/>Fig.4 Stress diagram of static ring seat(internal pressure)

图4 静环座应力图(内压)
Fig.4 Stress diagram of static ring seat(internal pressure)

图5 石墨环应力图(外压)<br/>Fig.5 Graphite ring stress diagram(external pressure)

图5 石墨环应力图(外压)
Fig.5 Graphite ring stress diagram(external pressure)

表1 静环热压加工工艺<br/>Tab.1 Hot-pressing processing technology for static ring

表1 静环热压加工工艺
Tab.1 Hot-pressing processing technology for static ring

表2 热环境作用下石墨环与静环座过盈量变化量<br/>Tab.2 Variation of interference between graphite rings and stationary rings under thermal environment

表2 热环境作用下石墨环与静环座过盈量变化量
Tab.2 Variation of interference between graphite rings and stationary rings under thermal environment

图6 石墨环受力示意图<br/>Fig.6 Graphite ring force diagram

图6 石墨环受力示意图
Fig.6 Graphite ring force diagram

图7 不同石墨材料静环受热分析<br/>Fig.7 Heating analysis of static ring of different graphite materials

图7 不同石墨材料静环受热分析
Fig.7 Heating analysis of static ring of different graphite materials

图8 石墨B静环变形分析<br/>Fig.8 Deformation analysis of graphite B static ring

图8 石墨B静环变形分析
Fig.8 Deformation analysis of graphite B static ring

图9 静环高温试验部分测量数据<br/>Fig.9 Measurement data of high temperature test part of static ring

图9 静环高温试验部分测量数据
Fig.9 Measurement data of high temperature test part of static ring

图10 密封面平面度变形规律<br/>Fig.10 Deformation law of flatness of sealing surface

图10 密封面平面度变形规律
Fig.10 Deformation law of flatness of sealing surface

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备注

引言

1 机理分析及数学模型

2 热压工艺

3 故障分析

4 结论

期刊信息