Selection Of Minimum Autofrettage Pressure for Steel Made Hydraulic Cylinder & Deciding Corresponding Re-Autofrettage Parameters

Abstract

Thick cylinders are widely used in High pressure application like Hydraulic power cylinders The Autofrettage process is an important part of the material optimization process for thick walled cylinders. In Autofrettage Intentional Residual stress were created due to plastic deformation of internal cylinder wall, so that during pressure loading phase some of stresses can be reduced as Working stresses & Residual stresses were opposite in nature The right hydraulic cylinder pressure is crucial for Autofrettage. To optimize material and reduce costs, industrial hydraulic cylinder manufacturers need the right minimum pressure for Autofrettage.. In this article problem of deciding right Initial Autofrettage pressure was solved for actual Manufacturer in India. The process involves correctly analyzing the material and its properties, followed by deciding the pressure range based on an analytical method, Finite Element Analysis is then used to validate the same. Re-Aufofrettage process was also been conducted for second sample Hydraulic Cylinder.