Page 282 - Failure Analysis Case Studies II
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Failure Analysis Case Studies II
D.R.H. Jones (Editor)
0 2001 Elsevier Science Ltd. A11 rights reserved 267
Failure analysis of rubber fuel pipes in aero-engines
Guoru Fu
Beijing Aeronuuticul Technoiogy Research Center, Box 9203- 16, Beging 100076, China
Received 19 May 1998; accepted 14 September 1998
Abstract
This paper describes a series of examinations and the fracture analysis of burst rubber fuel hosepipes on
aero-engines. The bursting of the hosepipes was caused by fatigue failure and major reasons are improper
design of hosepipe structure, low fatigue bearing capacity and severe deformation in mounting. 8 1999
Published by Elsevier Science Ltd. All rights reserved.
Keywork Aircraft failures; Engine failure; Fatigue; Hosepipes
1. Introduction
The bursting of rubber fuel hosepipes on aero-engines seriously compromises flight safety.
Though much research has done, the problem has not been solved. At least 10 incidents were
recorded in 1994-1995 alone. The bursting happened in two types of hosepipes which we designate
as A and B respectively for convenience. This article describes the characteristics of bursting
hosepipes, analyzes the failure and proposes prevention measures.
2. Visual inspection of hosepipes
The characteristics of bursting hosepipes are as follows:
(1) There were, to some extent bending deformations in both ends of the hosepipes, with more
deformation taking place near the end of the elbow pipe (see Fig. 1).
(2) For most hosepipes only one opening existed in the exterior of the rubber at the bending
position near the end of the metal elbow adapter, but two openings were observed in one A
type hosepipe.
(3) The distance from the bursting position to the end of the adapter housing was 0-15 mm.
(4) The bursting shape of the outer rubber was irregular and there with axial, circumferential and
branched cracking.
Reprinted from Engineering Failure Analysis 6 (3), 173-180 (1999)