{"id":17006,"date":"2016-11-21T06:24:27","date_gmt":"2016-11-21T06:24:27","guid":{"rendered":"http:\/\/www.safetyangel.com\/recdev\/?page_id=17006"},"modified":"2016-11-21T06:34:52","modified_gmt":"2016-11-21T06:34:52","slug":"blocksim-example-6-modeling-failure-modes-fault-trees","status":"publish","type":"page","link":"http:\/\/www.safetyangel.com\/recdev\/blocksim-example-6-modeling-failure-modes-fault-trees\/","title":{"rendered":"BlockSim Example 6 – Modeling Failure Modes (Fault Trees)"},"content":{"rendered":"
\r\n

BlockSim Example 6 - Modeling Failure Modes (Fault Trees)<\/h2><\/div><\/div><\/div><\/div><\/div>
<\/div><\/div>
<\/div>
\n

Examples provided here are purely for illustrating software features and functionality.<\/span><\/h3>\n<\/div><\/div><\/div><\/div><\/div><\/div><\/div>
<\/div>
\n

BlockSim Example 6 – Modeling Failure Modes (Fault Trees)<\/span><\/h3>\n

Download Example File for Version 10 (*.rsgz10)<\/a> or Version 9 (*.rsr9)<\/a><\/b><\/p>\n

In Example 4, we used a reliability block diagram (RBD) approach to analyze a component and its associated failure modes. In this example, we will use the same component and conditions described in example 4, but use a fault tree diagram instead of an RBD to perform the analysis.<\/p>\n

Example<\/span><\/h3>\n

The component can fail due to six independent primary failure modes: A, B, C, D, E and F. The component fails if mode A, B or C occurs. If mode D, E or F occurs alone, the component does not fail; however, the component will fail if any two (or more) of these modes occur (i.e., D and E; D and F; E and F). Furthermore, modes A, B and C can be broken down further into the events (sub-modes) that can cause them. Once a mode occurs, its sub-mode also occurs and does not go away.<\/p>\n

The following RBD illustrates the relationship between the primary modes.<\/p>\n<\/div>

\"\"\/<\/div><\/div>
\n

Figure 1: RBD of Component<\/p>\n<\/div><\/div>

The following diagram shows the corresponding fault tree of the component. The voting gate, represented by 2\/3<\/b>, replaces the node in the RBD.\u00a0The vote number in the voting gate is set to 2<\/b>, which indicates that at least 2 of the 3 basic events must occur for the component to fail.<\/div>
\"\"\/<\/div><\/div>
\n

Figure 2: Fault Tree Diagram of Component<\/p>\n<\/div>

\n

Mode A<\/h3>\n

There are five independent<\/b> (i.e., if one mode occurs, the rest are not more likely to occur) sub-modes associated with mode A: events S1, S2, T1, T2 and Y. There are three possible ways for mode A to manifest itself:<\/p>\n