Web Services Oriented Architecture (WSOA) supports development of high quality applications based on a control–flow between services. The introduction of a loop to deal with a dataset inside an orchestration is a typical evolution use case inside a WSOA, but there is no tool sup- port to perform such refactoring operation. In this paper we propose a new method to refactor an orchestration deal- ing with a variable v so that it iterates over a dataset v⋆ automatically. This algorithm is then validated on a run- ning software used as a validation platform by the French research project called FAROS.