Hydraulic chunk with function of compensatory clamping

Abstract

The invention discloses a hydraulic chunk with function of compensatory clamping, which comprises a piston, a hollow piston rod, a cylinder barrel, a connecting cover, a disc spring, a aligning roller bearing, a slip sleeve, a main shaft, a thrust bearing and a slip. The piston rod and the piston are sleeved in the cylinder barrel, the piston is fixed at the top end of the piston rod, the connection cover and the cylinder barrel are fixedly connected, one end of the disc spring is positioned on the shaft shoulder of the main shaft and the other end is positioned on the slip sleeve, the slip sleeve is arranged at the hollow part of the piston rod and is sleeved on the main shaft, a bearing positioning ring is arranged in the middle of the slip sleeve, the aligning roller bearing and the thrust bearing are respectively arranged at the two ends of the bearing positioning ring on the slip sleeve and positioned at the hollow part of the piston rod, and the slip is arranged in the slip sleeve. By the invention, the requirement of a high-torque drilling machine on great clamp force is met; a ring-shaped double-acting oil cylinder is used for auxiliary clamping so that a problem on deformation failure of a spring can be solved; and hydraulic pressure can be converted into clamping force by utilizing a cavity among the hydraulic cylinder barrel, the piston and the piston rod. The invention has the advantages of simple structure and long service life.

Description

technical field [0001] The invention relates to a hydraulic chuck for a drilling machine, in particular to a hydraulic chuck capable of compensating clamping. Background technique [0002] The hydraulic chuck is an important working part for clamping the drill pipe when the drilling rig is working, and transmitting torque to realize the rotary cutting and drilling of the drill bit. The reliability of clamping is the key to the normal operation of the drilling rig. At present, the hydraulic chucks of existing domestic drilling rigs include: spring force clamping, hydraulic pressure release (clamping is normal); hydraulic clamping, spring force release (releasing is normal); hydraulic clamping, loosening type. [0003] The spring-clamped hydraulic chuck will gradually decrease with the fatigue of the spring due to the elastic force of the spring, so that the clamping force cannot meet the requirements and fail. The existing hydraulic chucks for clamping compensation are gener...

AI Technical Summary

Problems solved by technology

[0003] The spring-clamped hydraulic chuck will gradually decrease with the fatigue of the spring due to the elastic force of the spring, causing the clamping force to fail to meet the requirements

The existing hydraulic chucks for clamping compensation are generally two external oil cylinders parallel to each other. Although the hydraulic compensation of clamping force can be realized, the symmetry of the installation of the oil cylinders, the synchronization of the hydraulic cylinders, and the identity of the extension length of the oil cylinders etc. will cause the oil cylinder to stretch out out of sync and cause partial load, which will cause bearing damage and make the chuck invalid.

[0004] The hydraulically clamped chuck uses hydraulic oil to cause the rubber sleeve to shrink radially to achieve clamping. When the torque is large or impacted, there will be relative rotation between the rubber sleeve and the slips, and the rubber sleeve is easy to wear. In addition, the slag Loading into slips and sleeve assembly can cause sleeve breakage and chuck failure

In addition, due to the safety setting requirements of the drilling rig, when using a hydraulically clamped chuck, it must be equipped with a spring clamped clamp, and the spring of the clamp also has the problems of fatigue and clamping force drop

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