Working Principle of Guangzhou Rotary Drilling Roller Cone Bit

　　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 to connect with 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 a water hole flow channel, and an oil storage pressure compensation device can be installed. 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 teeth. The cone is composed of... The single-cone bit moves purely by rolling at the bottom of the well, suitable for drilling in hard formations. The multi-cone consists of three parts: the main cone, the secondary cone, and the back cone. This type of cone can produce sliding in addition to rolling when working at the bottom of the well, and is used for drilling in 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 hard alloy teeth of different sizes and shapes; steel teeth are directly milled from the cone body. The rows of teeth on the three cones of the bit mesh with each other, which can effectively and non-repetitively break the rock at the bottom of the well and prevent 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 more numerous they are.