Automatic centering and deviation-adjusting sealing device for wellhead of oil well

Abstract

The invention relates to an automatic centering and deviation-adjusting sealing device for an oil well mouth, which belongs to oil well mouth equipment and is formed by sequentially connecting an internal thread connector, a centering and deviation-adjusting device and a blowout prevention box, and the centering and deviation-adjusting device is formed by sequentially connecting a universal connector, a main packing cylinder and an auxiliary packing cylinder from bottom to top. The universal connector is in threaded connection with a lower opening of the main packing cylinder, an upper opening of the main packing cylinder is in threaded connection with a lower opening of the auxiliary packing cylinder, and an upper opening of the auxiliary packing cylinder is in threaded connection with a lower opening of the blowout prevention box. Horizontal sealing holes are formed in the main packing cylinder and the packing cylinder, sealing blocks and sliding blocks are sequentially inserted into the sealing holes from inside to outside, and the thrust rotating disc is clamped outside the sliding blocks and matched with the sliding blocks in a rotating mode. According to the device, the automatic centering and deviation adjusting function can be achieved, automatic translation centering of 14 mm and automatic deviation adjusting of 2 degrees can be achieved, sealing blocks in the main packing cylinder and the auxiliary packing cylinder forcibly center a polish rod in the packing cylinders, the problem of eccentric wear of packing and a packing box is solved, meanwhile deviation adjusting and center fixing are combined, and the deviation adjusting angle is increased.

Description

technical field [0001] The invention belongs to oil well wellhead equipment, in particular to an oil well wellhead automatic centering offset adjustment sealing device. Background technique [0002] The problem of eccentric wear in the pumping unit is becoming more and more prominent. As the wellhead sealing device of the rod pumping unit, the packing box is the weakest link of the whole machine, and its sealing performance is greatly affected by the eccentric wear. Since it is impossible to achieve absolute accurate alignment in the installation of the pumping unit, the misalignment of the wellhead and the polished rod will cause serious partial wear of the polished rod, which will shorten the service life of the packing box and increase the power consumption. At the same time, according to statistics, 80% of rod pumping wells have an axis offset of 3-10mm, which leads to serious partial wear of the polished rod packing, which reduces the service life of the packing, and ev...

AI Technical Summary

Problems solved by technology

Since the installation of the pumping unit cannot achieve absolute precise alignment, the misalignment between the wellhead and the polished rod will cause serious partial wear of the polished rod, resulting in shortened service life of the packing box and increased power consumption

At the same time, according to statistics, 80% of pumping wells with rods have axis deviation of 3-10mm, which leads to serious eccentric wear of the polished rod packing, thereby reducing the service life of the packing, and even causing the friction between the packing box and the polished rod to cause the polished rod to shave , more seriously, after the seal wears out, the pressure in the oil well will carry the oil and gas in the well to emerge from the sealing box to pollute the wellhead or the well site

At the same time, the existing sealing device needs to stop the well to replace the packing, resulting in a long shutdown time

[0003] The publication with the patent No. 2021200755327 solves the above-mentioned problems to a certain extent, but it is "composed of coaxial cylindrical blowout preventers, sealing cylinders, sealing devices and deflection adjustment joints sequentially connected from top to bottom", because Its structure is equipped with a sealing device, which leads to troublesome installation and high cost. At the same time, the polished rod cannot be fixed in the center, and the problem of partial wear of the packing box cannot be overcome. Moreover, its deflection adjustment effect is limited, and it can only be adjusted by 0.5 degrees.

In addition, it is powerless to wells with high water content and heavy oil wells, and its packing cannot be sealed to prevent oil leakage.

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