What Is the Movement Status of the Insert Three Cone Bit?

In oil drilling, the inserted three cone bit is one of the main rock-breaking tools and can adapt to various geological formations. The motion and force of the roller cone bit at the bottom of the well is quite complex. The movement of the three cone bit at the bottom of the well determines the movement of the teeth on the drill bit, which directly determines the crushing effect of the teeth on the rock formations. Therefore, before understanding the working principle of the drill bit for breaking rocks, it is necessary to understand the movement of the drill bit at the bottom of the well.

What is the motion state of the inserted three cone bit?

Self-rotation of the drill bit: When the tricone roller bit rotates, when viewed along the direction from the bottom plane of the bit to the tip of the bit, the tri-cone rotates counterclockwise around its own axis, which is called self-rotation. The rotation of the tri-cone is the result of the reaction of the rock against the teeth. The factors affecting the speed of the tri-cone's self-rotation include the speed of the bit's rotation, the structure of the bit, the surface structure of the teeth, the drilling parameters, and the properties of the rock formations. In general, the speed of the tri-cone's self-rotation is faster than the speed of the bit's rotation. The ratio of the speed of the tri-cone's self-rotation to the speed of the bit's rotation is called the gear ratio, which is generally between 1-1.5.

Revolution of the drill bit: The rotation of the tri-cone around the axis of the drill bit in a clockwise direction is called the revolution of the drill bit. The speed of the drill bit's revolution is the rotation speed of the turntable or downhole drilling equipment. When the drill bit revolves, the tri-cone rotates around the axis of the drill bit, and the linear speed of each row of teeth on the tri-cone rotating around the axis of the drill bit is different, with the outer teeth having a larger linear speed.

How is the inserted three cone bit used?

• Use a new type of high-temperature-resistant and wear-resistant lubricating grease that can withstand temperatures of up to 250℃.

• Use metal sealing. The metal seal consists of a pair of designed and processed metal sealing rings as the bearing axially dynamic seal, and two high-elastic rubber energy-supplying rings are respectively located in the sealing areas of the tooth palm and the tri-cone as static seals. The optimized sealing compression ensures that the sealing surfaces of the two metal sealing rings always maintain good contact.

• The inserted drill bit uses high-toughness hard alloy teeth, optimized design of the number of tooth rows, number of teeth, height of exposed teeth, and special shapes of the teeth, fully displaying the high wear resistance and excellent cutting ability of the inserted drill bit. The steel-tooth drill bit has a new type of wear-resistant material welded to the tooth surface, which not only maintains a high mechanical drilling speed of the steel tooth tricone drill bits, but also improves the cutting tooth life of the drill bit.

• Steel ball locking is used for the tri-cone drill bit to adapt to high speeds.

• Use a fully rubber storage bag that can limit the pressure difference and prevent drilling fluid from entering the lubrication system to provide good lubrication for the bearing system.

• A floating bearing structure is used, and the floating member is made of new materials with high elasticity, high temperature resistance, high wear resistance, and its surface has been treated with solid lubricant. While reducing the relative linear velocity of the bearing pair, it can also reduce the temperature rise of the friction surface, and improve the bearing life and performance under high drilling pressure or high rotation speed drilling conditions.

We need to pay attention to maintaining and operating the inserted three cone bit correctly to reduce the damage rate of the three cone bit and improve work efficiency. The quality, speed, and cost of drilling are all affected by the choice and use of the drill bit, so selecting the right drill bit and using it correctly is a very important matter.