Subsea Drilling Riser Wear: A Case History

Abstract

ABSTRACT Wear in subsea drilling risers and BOP equipment while drilling can be an expensive problem. If the wear causes loss of riser integrity the risk to personnel and equipment is potentially significant due to the well control situation that could result. This paper presents information on a serious riser/BOP wear occurrence that resulted in serious well control problems and an expensive equipment repair. The case study presented here occurred in only 295 ft of water in a relatively short period of drilling time. The approximate cost of the resulting problems was in excess of US$3.5 million. This paper will also present a simple model that can be used to estimate the wear in a riser and flex joint. The calculations in this paper will provide a means to determine the relative effects of such parameters as riser angle and tooljoint hardbanding abrasiveness. With this knowledge it is possible to develop an informed riser wear management program.