ISSN: 1945-7553
CODEN: JTEVAB
Published Online: 22 January 2013
Page Count: 8

Failure Analysis of a Set of Flapper Valves Under ALT With Alternative Test Device

Martins, J. A.
State Univ. of Campinas, Materials Engineering Dept., UNICAMP, Cidade Universitária 13083-970-Campinas,

Ferreira, I.
State Univ. of Campinas, Materials Engineering Dept., UNICAMP, Cidade Universitária 13083-970-Campinas,

Leite, D.
Head of Quality Dept., Associated Spring do Brasil, A business of Barnes Group Inc, Campinas,

Romão, E. C.
Federal Univ. of Itajubá, Itabira, MG

(Received 16 November 2011; accepted 23 August 2012)

Abstract

In search of further understanding and continuous improvement of mechanical products which suffer dynamics loading, several methods of analysis have been applied, among them, computational simulations and laboratorial experiments. This paper aims to describe the failure mechanics of a regular flapper valve and valve reed used on Hermetic Compressors when tested under accelerated test conditions by a special device, created for testing purpose. The results obtained from the valve reed were plotted on a graph, which reveals the endurance under fatigue, versus the device speed/load change. These curves represent the obtained valve reed lifetime by Weibull ALT (accelerated life test) (statistical analysis). The values obtained were analysed using the normality and the probability approaches beyond t-student. The Weibull ALT graph (fatigue lifetime), microscopic analysis by SEM (scanning electron microscope) and EDS (energy dispersive spectroscopy) were performed on the failed valve reed surface as well as on the valve plate seat utilised throughout the tests.

Keywords:
product testing device, valve reed, fatigue, corrosion

Paper ID: JTE20120173
DOI: 10.1520/JTE20120173
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