航改燃气轮机燃烧室故障模式、影响及危害性分析

Failure Mode,Effects and Criticality Analysis of Aero-derivative Gas Turbine Combustor

为提高航改燃机燃烧室可靠性及使用安全性,在设计阶段对某型中等功率航改燃气轮机燃烧室进行故障模式、影响及危害性分析(FMECA)。根据燃烧室结构组成,建立硬件层次及可靠性逻辑框图。针对燃烧室机匣、火焰筒、燃油总管、燃油喷嘴、导流罩等零部件进行故障模式分析,指出可能发生故障的原因及其影响,并有针对性地提出改进措施。根据各零部件发生故障的概率及严重程度建立危害性矩阵,找出系统的薄弱环节,得到FMECA表。结果表明:火焰筒壁面掉块及燃油总管焊缝开裂是影响燃烧室性能及使用安全性的主要因素,应采取相应措施降低其发生概率及严重程度,同时指出对于发生概率及严重程度较低的故障可以适当降低其设计成本。运用FMECA表客观地找出系统薄弱环节,为后续燃烧室维护及测试提供参考。

In order to improve aero-derivative gas turbine combustor reliability and safety,Failure Mode,Effects and Criticality Analysis(FMECA)of a medium power aero-derivative gas turbine combustor were carried out in design stage.According to the combustor structure,hardware hierarchical block diagram and reliability logic block diagram were established.Failure modes were analyzed for combustor casing,flame tube,fuel manifold,fuel nozzle and cowl.The causes and effects of possible faults were pointed out,and targeted improvement measures was put forward.Criticality matrix was established based on failure probability and severity of each component.The weak links of the system were found out and FMECA analysis table was listed.The results show that the loss on the wall of the flame tube and the weld cracking of the fuel manifold are the main factors affecting the performance and service safety of the combustor.Corresponding measures should be taken to reduce the occurrence probability and severity.At the same time,it is pointed out that the design cost can be appropriately reduced for the faults with low occurrence probability and severity.FMECA analysis table can be used to objectively find out the weak of the system and provide reference for subsequent combustor maintenance and test.