Combined bidirectional long-stroke push-and-pull hydraulic cylinder

Abstract

The invention discloses a combined bidirectional long-stroke push-and-pull hydraulic cylinder, which comprises an external cylinder and an internal cylinder. The external cylinder comprises an external cylinder barrel, an external cylinder lug, an external cylinder piston and an external cylinder piston rod, wherein the external cylinder piston is movably arranged in the external cylinder barrel; one end of the external cylinder piston rod is fixed on the external cylinder piston while the other end is fixedly connected with the external cylinder lug; and the external cylinder barrel is hermetically connected with the external cylinder piston rod. The internal cylinder comprises an internal cylinder barrel, an internal cylinder piston and an internal cylinder piston rod, wherein the internal cylinder barrel is arranged in the external cylinder piston rod; the bottom of the internal cylinder barrel is adjacent to the external cylinder lug; the internal cylinder piston is movably arranged in the internal cylinder barrel; one end of the internal piston rod is fixed on the internal cylinder piston, and the internal cylinder barrel is hermetically connected with the internal cylinder piston rod; and the external cylinder barrel is fixedly connected with the internal cylinder barrel. Because the axial size of the combined bidirectional long-stroke push-and-pull hydraulic cylinder is reduced by 40 percent, a structure of a drilling machine is compact and the combined bidirectional long-stroke push-and-pull hydraulic cylinder is particularly suitable to be applied to environments of tunnels and coal mine galleries, can make the pull-back force meet the requirements, shorten the length of a stand of the drilling machine and lighten the weight, and is flexible and convenient to move.

Description

technical field [0001] The invention relates to a hydraulic cylinder for a drilling rig, in particular to a combined two-way long-stroke push-pull hydraulic cylinder. Background technique [0002] The hydraulic cylinder is an important working element to propel the drill pipe when the drilling rig is working. The stroke of the hydraulic cylinder is determined by the length of the drill pipe. For ordinary double-acting single-stage cylinders, the stroke of the hydraulic cylinder determines the initial installation length of the hydraulic cylinder and Rack length and even host length. At present, the frame length of various drilling rigs is restricted by the length of the hydraulic cylinder. Especially in the occasions where the use space is limited, the hydraulic cylinder with long stroke and short initial length is urgently needed by various drilling rigs. Although the existing two-stage cylinder has a long stroke, due to the limitation of the structure of the two-stage cy...

AI Technical Summary

Problems solved by technology

Although the existing two-stage cylinder has a long stroke, due to the limitation of the structure of the two-stage cylinder, the retraction force is too small to meet the needs of the drilling rig to pull back the drill pipe, so the application of the two-stage cylinder on the drilling rig is limited

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