failure rate curve

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Failure rate curveclick for a larger image
Fig. 40 Failure rate curve. Graph showing a typical curve.

failure rate curve

or

‘bath tub curve’

or

Weibull analysis

a curve which reflects the RELIABILITY of a component of a product or machine, measured in terms of the proportion of a sample of that component which fails at different phases of its operational life. Fig. 40 shows a typical failure rate curve for a sample of the component which is divided into three phases:
  1. the ‘infant’ or burn-in period of the component is characterized by an initial high rate of failure. The early failure rate then decreases rapidly as surviving components prove themselves to be reliable;
  2. the adult or normal useful life period of the component is typified by a low and relatively constant rate of component failure;
  3. the ageing or wear-out period of the component is characterized by a rise in the failure rate as the component reaches the end of its designed life.

Each of these phases will reflect the adequacy of the design of the component, the quality of the materials used to make it, and the consistency with which it is manufactured.

In designing finished products, firms may seek to reduce the extent of early failure of components by laboratory testing of new product designs, and by using feedback from consumer panels and test marketing to perfect the design of the product. In determining GUARANTEE or WARRANTY periods for products, firms need to be aware of when the components of the product are likely to reach the end of their normal useful life and begin to experience rising failure rates. Failure rate profiles for components of factory machines can likewise be employed to plan the firm's MAINTENANCE and machine replacement programmes. See QUALITY CONTROL.

Collins Dictionary of Business, 3rd ed. © 2002, 2005 C Pass, B Lowes, A Pendleton, L Chadwick, D O’Reilly and M Afferson
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References in periodicals archive ?
Solder joint integrity was monitored in-situ to accurately identify duration to failure for Weibull analysis. The results clearly show this new generation of WLCSP structures can offer dramatically improved fatigue life without a significant sacrifice in drop reliability.
Weibull analysis is a well-known method typically used for fracture statistics for brittle materials.
Weibull analysis is a function usually has been used for calculating the probability for fracture in brittle materials.
Platz, "Evaluation of uncertainty in experimental active buckling control of a slender beam-column with disturbance forces using Weibull analysis," Mechanical Systems and Signal Processing, vol.
[16.] Dodson, B., The Weibull Analysis Handbook, Second Edition, ASQ Quality Press, Milwaukee, Wisconsin, 2006.
The latter were subjected to Weibull analysis (20) to determine the characteristic strength (i.e., the strength at a 63.21% failure probability, which represents a more objective measure of strength than its average value), and the reliability of the tested material, based on the Weibull modulus to quantify the distribution of the strengths of the different samples.
His topics include crack basics, stress corrosion, slow crack growth with residual stress, stress-time approximation, Weibull analysis, determining inert strength, moist environments, crack propagation, and putting it all together again.
Candela, "A new algorithm for mixed Weibull analysis of partial discharge amplitude distributions," IEEE Transactions on Dielectrics and Electrical Insulation, vol.
Robert Abernethy in his famous textbook on Weibull analysis: The New Weibull Handbook.