Failure Mode and Effects Analysis
A failure mode and effects analysis FMEA is a design-evaluation procedure used to identify potential failure modes and determine the effect of each on system performance. This procedure formally documents standard practice, generates a historical record, and serves as a basis for future improvements. The FMEA procedure is a sequence of logical steps, starting with the analysis of lower-level subsystems or components. Figure 2-1 illustrates a typical logic tree that results with a FMEA. The...
Control Valves
Control valves can be broken into two major classifications process and fluid power. Process valves control the flow of gases and liquids through a process system. Fluid-power valves control pneumatic or hydraulic systems. Process-control valves are available in a variety of sizes, configurations, and materials of construction. Generally, this type of valve is classified by its internal configuration. The device used to control flow through a valve varies with its intended function. The more...
FaultTree Analysis
Fault-tree analysis is a method of analyzing system reliability and safety. It provides an objective basis for analyzing system design, justifying system changes, performing trade-off studies, analyzing common failure modes, and demonstrating compliance with safety and environment requirements. It is different from a failure mode and effect analysis in that it is restricted to identifying system elements and events that lead to one particular undesired event. Figure 2-2 shows the steps involved...
Pumps 1
Design, installation, and operation are the dominant factors that affect a pump's mode of failure. This chapter identifies common modes of failure for centrifugal and posi- Centrifugal pumps are especially sensitive to variations in liquid condition i.e., viscosity, specific gravity, and temperature suction variations, such as pressure and availability of a continuous volume of fluid and variations in demand. Table 19-1 lists common failure modes for centrifugal pumps and their causes....
CauseandEffect Analysis
Cause-and-effect analysis is a graphical approach to failure analysis. This also is referred to as fishbone analysis, a name derived from the fish-shaped pattern used to plot the relationship between various factors that contribute to a specific event. Typically, fishbone analysis plots four major classifications of potential causes i.e., human, machine, material, and method but can include any combination of categories. Figure 2-4 illustrates a simple analysis. Like most of the failure...