Application of the hydraulic cutter in the treatment of bit burning in core drilling

Abstract:

The formation in ZK1102 core drilling hole in the peripheral pre-survey area of Zhongba， Ningqiang county was fracture-developed， and the drilling leakage was serious. Due to insufficient pumping time， the drilling fluid had not reached the bottom of the hole when drilling began， resulting in a serious bit burning accident. The optimum accident treatment scheme was selected through scientific analysis and assessment based on the equipment characteristics of the portable full hydraulic drill and the formation conditions， at the prerequisite to guarantee the prospecting results， and the safety， economy and reliability of accident treatment. The BTW drill pipe was used to connect the hydraulic cutter for cutting the accident section in the drilling string， and then the NTW tool to connect the grinding mill to mill out the remaining drill bit； in such a way， the drilling accident was solved efficiently， economically and safely. With reference to field applications of the hydraulic cutter， the causes for cutting failure are analyzed and summarized under different operation sequences and cutting parameters， which has accumulated rich field experiences for on-site operators and laid a solid technical foundation for smooth handling of bit burning accidents. In this paper， the use of the hydraulic cutter to deal with core drilling bit burning accidents has been actively explored， which provides reference for other areas to use the hydraulic cutter to deal with similar complex drilling accidents.

Key words:hydraulic cutter;portable full hydraulic drill;bit burning;accident treatment;grinding