Analysis Fracture Failure Analysis of Drill Pipe’s Tool Joint

Abstract:

One drill pipe’ tool joint fractured rarely after just servicing ten days in drilling process of one natural gas well. Failure reason of tool-joint pin was researched through visual inspection, mechanical properties testing and working condition analysis. Results show that fracture failure reason is mainly due to the dramatic friction between the tool joint and the accumulated debris during the drill-string’s rotating process. Accumulated debris blocked mud’s circulation channel and leaded to poor circulation. The dramatic friction between the tool joint and accumulated debris leaded tool joint’s local temperature to risen significantly, and reduced its carrying capacity. In the end, tool joint fractured under the effect of tensile and torsional loads.

• Periodical: Applied Mechanics and Materials (Volumes 713-715)
• Pages: 65-68
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.713-715.65
• Online since: January 2015
• Authors: Fang Po Li*
• Keywords: Downhole Accident, Failure Analysis, Friction Cracking, Tool Joint

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