Hydraulic anchor

Abstract

The invention relates to a hydraulic anchor. Anchor teeth are arranged on anchor claws, an oil pipe internal thread is arranged on the upper part of an anchor body, an oil pipe external thread is arranged at the lower part of the anchor body, and the oil pipe internal thread at the upper part of the anchor body is matched with the oil pipe external thread at the lower part of the anchor body. Anchor holes are formed in the anchor body, the anchor holes are reducing holes, the outer end diameters are less than the inner end diameters, and two diameter sections form a table shoulder. Two cylindrical sections which are matched with the anchor holes are arranged on the anchor claws, right sealing rings are arranged on the large-diameter sections of the two cylindrical sections, the anchor claws are arranged in the anchor holes, baffle sleeves are arranged in the anchor body to enable the anchor claws to be not separated away from the anchor holes. Left sealing rings are arranged on the small diameter sections of the two cylindrical sections on the anchor claw, injection holes are formed in the anchor claws, the injection holes communicate with the space formed by the anchor holes and the anchor claws, and one-way injection valves are arranged at the outer ends of the injection holes. A spring is not required to be arranged, the various problems caused by the spring are eliminated,the anchor claws can be reliably reset, and the clamping pipe column failure that the anchor claws cannot be recovered is avoided.

Description

technical field [0001] The invention is a device used in an oil pumping well in an oil field, and is an anchoring device for an anchoring pipe string, in particular a hydraulic anchor. Background technique [0002] When pumping oil in an oil well, the fluid column load is alternately transferred on the tubing and the sucker rod with the change of the up and down stroke of the pumping unit, which makes the tubing elongate and shorten, resulting in low pump efficiency, reduced production, tubing bending and shortened service life, and the fluid column load Alternately acting on the oil pipe can also easily cause the oil pipe to trip and fall into the well. In order to avoid the above problems, a hydraulic anchor was used on site to fix the oil pipe and prevent the oil pipe from expanding and contracting. During the construction of some oil-water wells, in order to prevent damage to downhole tools such as packers caused by pipe string movement, hydraulic anchors should also be...

AI Technical Summary

Problems solved by technology

Since the inner diameter of the anchor body of the hydraulic anchor is greater than Φ60mm, the outer diameter is less than Φ114mm, and its side wall thickness is only 27mm, the anchor claw and spring should be designed and installed in the anchor hole with a diameter of Φ50mm on the side wall of the 27mm anchor body, so The size of the spring is small and the elastic force is limited. It is difficult to overcome the friction between the sealing ring on the fluke and the anchor hole. When the lifting string needs to be retracted, the fluke cannot be retracted, causing the string to be stuck and engineering accidents to occur.

Since the spring is soaked in the well fluid, the spring is easily corroded and damaged, the function of the spring decreases or disappears, and the anchor fluke cannot be retracted.

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