Research And Application Of Casing Protection Tools

In the drilling operations of deep well and extended reach well, because of long drilling time and complicated drilling pipe movement, rub and worn-out problems of casing and drill string become more and more predominate. The original analysis of the casing wear phenomenon in the drilling progress and general casing wear protective measures was carried out. According to different principles causing casing wear, the mechanism of casing wear and decreasing torque was studied, then the mathematical model of casing wear and decreasing torque was established.FM series casing protection tools are drill stem type tools. The operating principle, architecture feature, normal ordinance mode of tools were described in the artical. Friction pairs of hard metal TC friction pairs, drilling fluid exposed lubrication were used in the tools for low coefficient of friction, well abrasion resistance, long service life and low risk under the hole.Software was developed. The software has functions of output, memory store, and amicable interface. It's operation is convenient, and can be easily mastered by engineers and technicians.The laboratory experiment and onsite application indicate that: the tool has obvious protection effect and is long life, safe and reliable, low integrated cost. The tool should resolve the casing wear problem in the well drilling process and has a very extensive application foreground.