Reliability HotWire

Issue 100, June 2009

Tool Tips

* When should I use a Phase Diagram in BlockSim?
In BlockSim 7, a phase diagram can be used to represent and analyze a system whose reliability configuration and/or other properties change over time. In other words, at different times during a mission the system may undergo changes in its reliability configuration (RBD), the available repair resources or the failure, maintenance and/or throughput properties of its individual components. Examples of this include:

  • Systems whose components exhibit different failure distributions depending on changes in the stress experienced by the system.
  • Systems or processes requiring different equipment to function in different stages of the operational cycle, such as start-up, normal production, shut-down, scheduled maintenance, etc.
  • Systems whose RBD configuration changes at different times, such as the RBD of the engine configuration on a four-engine aircraft during taxi, take-off, cruising and landing.
  • Systems with different types of machinery operating during day and night shifts and with different amounts of throughput during each shift.

To analyze such systems, each distinct operating condition during the mission can be represented by a "phase" block whose properties are inherited from an RBD corresponding to that phase's reliability configuration, along with any associated resources of the system during that time. A phase diagram is then a series of such phases connected in a sequence signifying the chronological order.

For more information about using phase diagrams in BlockSim 7, refer to the "Reliability Phase Diagram Analysis" article in the Reliability Edge, Volume 8, Issue 1. You can also refer to Chapter 11: Phase Diagram Sheets in the BlockSim 7 User’s Guide or to the "Reliability Phase Diagrams (RPDs)" chapter in the System Analysis Reference: Reliability, Availability and Optimization guide.

* Can I get a demonstration of the FMEA templates available in the FMEA Accelerator for use within Xfmea/RCM++?
Using FMEA templates prepared by experienced analysts who are knowledgeable about the components and the failure mode analysis process can be a powerful way to speed up and improve the quality of your FMEA or RCM analyses. By providing general descriptions of the typical functions, failures, effects and root causes along with potential mitigation strategies, FMEA templates can serve as the starting point for your own specific analyses and act as a guide to assist in identifying, assessing and addressing critical failure modes.

ReliaSoft's FMEA Accelerator® allows you to access an outstanding collection of FMEA templates for a wide variety of components for use in Xfmea or RCM++. If you would like more information about the types of components that are available and the level of detail in the template analysis, you can:

  • Review the MRG Physical Asset FMEA Template Collection PDF file, which lists the components available for purchase and provides the number of functions, failures, effects and causes defined for each component.
  • Download a free demonstration database that also shows what components are available and provides a partial analysis of three components: Gearbox_Oil Lubricated, Pump_Centrifugal_Mag Drive_Close Coupled and Pump_Centrifugal_Motor Drive.

Please note that the sample data in the demonstration database are intended to give you an idea of how the FMEA templates are structured and the type of information that is available. Each partial analysis consists of only 1 function, 1 or 2 potential functional failures and their related effects, causes and potential maintenance strategies. When you purchase a template, you will have access to the entire data set. For example, the partial Pump_Centrifugal_Motor Drive template that is distributed with the demonstration database contains 1 function, 1 potential functional failure, 1 possible failure effect and 5 possible causes of failure but the full template contains 4 functions, 22 potential functional failures, 22 possible failure effects and 70 possible failure causes.

Copyright © 2009 ReliaSoft Corporation, ALL RIGHTS RESERVED