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Software Used Note: This is the second part of a three-part series about standards based reliability prediction and ReliaSoft's newly introduced Lambda Predict software package. Introduced standards based reliability prediction and discussed when it is appropriate to use and when it should be avoided. This part discusses the different major reliability prediction standards. Part III will give an example of how standards based reliability prediction and Lambda Predict can be used to complete a Reliability Block Diagram (RBD) when data is not available.

Jul 12, 2010 Reliability calculation with RDF 2000: RELIABILITY DATA HANDBOOK Reliability Analysis.

Reliability prediction plays a major role in many reliability programs across government and industry. Standards based reliability prediction relies on defining failure rates for the components of a system based on predefined standards, depending on the types of components, the use environment, the way the components are connected and the reliability prediction standard. These component failure rates are then used to obtain an overall system failure rate. Over the past few decades, several standards have been introduced by various governments and industry organizations to assist in conducting this type of analysis.

The standards define models for different component types based on test data. The models assume a constant failure rate ( i.e. No wearout or early failures problem), which generally describes the useful life of a component where failures are considered random events. The following is an overview of the common standards that are available in as different modules. Note that Lambda Predict provides redundancy calculation in addition to each of these standards. MIL-217 Standard The MIL-217 standard is a reliability prediction program based on the internationally recognized method of calculating electronic equipment reliability given in MIL-HDBK-217 (published by the US Department of Defense).

This standard uses a series of models for various categories of electronic, electrical and electro-mechanical components to predict failure rates that are affected by environmental conditions, quality levels, stress conditions and various other parameters. These models are fully detailed within MIL-HDBK-217. This standard supports two methods of reliability prediction as described in MIL-HDBK-217F: Parts Count and Part Stress Analysis. Parts Count Method Parts Count generally requires information such as part quantities, quality levels and the application environment. Because it requires less information than Part Stress Analysis, it is most applicable early in the design phase and proposal formulation. Morceau De Concours Pdf Writer. Parts Count prediction defines the overall equipment failure rate as: where: n = Number of part categories Ni = Quantity of ith part = Failure rate of ith part = Quality Factor of ith part If the equipment consists of parts operating in more than one environment, then this equation is applied to each portion of the equipment that is operating in a distinct environment.