SciELO - Scientific Electronic Library Online

 
vol.11 issue3Analysis of a complex composite through digital electron microscopy and image analysisComparative evaluation of film thickness and compressive strength of glass ionomer luting cements, conventional versus resin modified glass ionomer author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Matéria (Rio de Janeiro)

On-line version ISSN 1517-7076

Abstract

THOMAZI, Cinthia Thaís de Carvalho Luz  and  LEVY NETO, Flaminio. Analysis of the deformations in steel pipes repaired with carbon/epoxy composites. Matéria (Rio J.) [online]. 2006, vol.11, n.3, pp.278-286. ISSN 1517-7076.  http://dx.doi.org/10.1590/S1517-70762006000300017.

The main objective of this work is to present the values of the circumferential normal deformations obtained from numerical simulations of metallic pipes (AISI Steel 1020, length L = 400 mm, external diameter D = 400 mm and thickness t = 2 mm) in the following conditions: (i) perfect; (ii) machined on 25% of its length along its central region to a thinckness reduction of 50%, in order to simulate a defect; and (iii) repaired with a carbon/epoxy composite (balanced woven fabrics of fibers, AS4 - Hexcel), subjected to different internal pressures, from 2 to 10 MPa, using the non linear finite element program COMPSHELL. And, in addition, to verify if the applied composite repairing are able to restore the original stiffness of the pipes, previous to the machining operation. It was observed that there is a minimum thickness, which is required for the carbon/epoxy repairing to restore the local stiffness lost on the machining operation. The radial displacements and the circumferential strain were used as references to evaluate how effective the repair was. The minimum thickness of the repairing depends on the ratio of the elasticity moduli of the repaired and the original material of the tube. As far as this work is concerned, the required repair thickness is 3.05 mm.

Keywords : composite repairings; metallic pipes.

        · abstract in Portuguese     · text in Portuguese     · Portuguese ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License