학술논문

Potential Ignition Mechanism of Buna-N O-Rings in Liquid-Oxygen
Document Type
stp-paper
Source
Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres: Ninth Volume, Jan 2000, Vol. 2000, No. 1395, pp. 207-223.
Subject
Buna-N O-rings
liquid-oxygen
failure analysis
elastomer ignition
mechanical impact
ANALYSIS OF IGNITION AND COMBUSTION
Language
English
Abstract
Buna-N O-rings used in liquid-oxygen dewars have been implicated in fires when subjected to a shearing load. Such a loading occurs when the dewar flange receives a mechanical impact due to the dewar falling over. The ignition event has been replicated under controlled conditions but only when the O-ring has been previously distorted such as could occur during improper seating of the seal in the upper flange, or when forced extrusion of the seal occurs while exposed to liquid-oxygen. This paper applies an ignition model to the experimental system to extend the parameterization of oxygen pressure/temperature to the extent of O-ring damage, shear energy and oxygen flow. The model allows for heat loss and variable generation rates.