Guangdong Factory Direct Rotary Drilling Roller Cone Leg

　　Cone Leg

　　A cone on which teeth are mounted (or milled), divided into single-cone and multi-cone types. The single cone consists of the main cone and the back cone. The cone leg is the main part of the roller cone bit. A bit is assembled and welded together from three cone legs. The upper part has a connecting thread for connection to the drilling tool, and the lower part is made into a journal with a certain inclination angle, which forms a bearing pair with the inner hole of the cone. The cone leg has water hole flow channels and can be equipped with an oil storage pressure compensation device. The journal bears the load and requires high wear resistance and hardness, while the interior of the matrix also needs sufficient strength and impact toughness. II. Cutting Structure The cutting structure includes the cone and the teeth. The cone is the component; the single-cone cone moves in pure rolling at the bottom of the well and is suitable for drilling hard formations. The multi-cone consists of three parts: the main cone, the secondary cone, and the back cone. This type of cone can not only roll but also slide when working at the bottom of the well, and is used for drilling softer formations. The teeth on the cone are divided into inserted teeth and steel teeth. Inserted teeth are made by drilling holes in the tooth rings on the outer conical surface of the cone and inserting cemented carbide teeth of different sizes and shapes; steel teeth are milled directly from the cone body. The rows of teeth on the three cones of the bit mesh with each other, effectively and without repetition crushing the rock at the bottom of the well and preventing bit balling. The shape, size, number, and length of the teeth depend on the hardness of the formation being drilled. The softer the formation, the larger and sharper the teeth and the fewer they are arranged. Conversely, the harder the formation, the smaller and shorter the teeth and the greater their number.