High-temperature resistant floating sealing device for cone bit

Abstract

The invention relates to a sealing device for a cone bit for petroleum, natural gas, mine and geological drilling, and belongs to the technical field of mechanical devices. The high-temperature resistant floating sealing device consists of a movable sealing ring, a stationary sealing ring, a welding corrugated pipe, a movable ring seat and a sand prevention seal; and the movable sealing ring, the stationary sealing ring, the welding corrugated pipe and the movable ring seat are mounted in a sealed cavity formed by an inner bore and a bit leg of a cone; the movable sealing ring is fixed on the cone through the welding corrugated pipe and the movable ring seat and can rotate along with the cone, and the movable sealing ring and the stationary sealing ring are tightly attached to form a movable seal for blocking the drilling fluid at the outer side of the welding corrugated pipe and the lubricant at the inner side of the welding corrugated pipe. The sand prevention seal comprises a rubber block and a steel wire block. According to the floating sealing device, the welding corrugated pipe is adopted to replace a rubber elastic element, so the movable seal is enabled to stably operate at high temperature; the welding corrugated pipe adopts a stepped slice structure and can prevent sediment from depositing in the outer side of the corrugated pipe; and the movable ring seat and the stationary sealing ring are prevented from falling off.

Description

technical field [0001] The invention relates to a roller cone bit sealing device used in petroleum, natural gas, mine and geological drilling, and belongs to the technical field of mechanical devices. Background technique [0002] The working condition of the bearing seal of the roller cone bit is relatively bad. With the further increase of the drilling depth of the formation, the high temperature downhole becomes the key factor restricting the rubber elasticity. The rubber components in the commonly used rubber seal or metal seal are sensitive to temperature. The nonlinear characteristics of rubber will cause the specific pressure of the metal seal end face to be extremely unstable. Chinese patent CN 101086197A proposes a single metal seal, the structure is mainly composed of a moving ring, a gasket ring fixed on the cone, a rubber seal and a rubber support ring, the rubber seal can provide axial force, and can also prevent mud from entering The sealing cavity needs to be...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the shortcomings of the existing dynamic sealing technology for roller cone bits, aiming at the characteristics of relatively large changes in rubber properties under high temperature conditions in ultra-deep wells, and to improve the existing dynamic sealing structure to provide a high temperature resistant roller cone Drill floating seal

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