New friction welding process for pipeline girth welds - parameter optimization

A promising new welding method for fully automatic welding of pipelines has been developed. The proposed welding procedure, called friction with an 'explosive' forge force (FRIEX), is a new variant of the well-known friction welding process. In the first part of the present paper, the working principles of the FRIEX welding process are described. Subsequently, a brief overview is given of small-scale experiments that have been conducted in order to demonstrate the practical feasibility of this welding process. The optimization of the shape of the welding ring is discussed. Finite element models have been developed which are able to predict the process behaviour under varying process parameters. Results of numerical simulations showed good agreement with experimental observations.