Follow-up type automatic compensation polished rod sealing device

Abstract

The invention provides a follow-up type automatic compensation polished rod sealing device and belongs to the technical field of oil field machinery. The follow-up type automatic compensation polished rod sealing device comprises a sealing cover, a sealing shell, a pressure adjusting spring, a translation pressing plate, an upper follow-up platform, a follow-up packing box, a lower follow-up platform and a sealing foundation support; the follow-up packing box is in close contact with a polished rod, parallel movement in any direction in the horizontal plane is conducted by means of the upper follow-up platform and the lower follow-up platform, and the problem of eccentric wear is effectively solved; the follow-up packing box is provided with compensation packing and centralization packing, close contact with the polished rod can be achieved under continuous pressure, the sealing effect is improved, and packing wear can be compensated continuously; an annular cavity formed by a sealing cover retaining ring and the sealing shell is filled with lubricating oil and can provide continuous lubrication and oil seal for the upper follow-up platform, the lower follow-up platform, the polished rod and even the packing, radial and axial friction is reduced, meanwhile multiple purposes of saving energy, sealing, prolonging the service life and the like are achieved, and the follow-up type automatic compensation polished rod sealing device can be widely applied to wellhead sealers of oil field pumping units with rods.

Description

technical field [0001] The invention relates to a follow-up type automatic compensation polished rod sealing device, which belongs to the technical field of oilfield machinery. Background technique [0002] The function of the sealing device of the polished rod of the traditional pumping unit is to implement a "lock" seal on the polished rod by pressing the wear-resistant packing to prevent the pressurized oil, gas and water in the oil well from coming out of the wellhead with the reciprocating movement of the polished rod. The problems of this kind of seal are mainly manifested in the following aspects: (1) Serious environmental pollution: "locking" seal will inevitably lead to wear of the packing ring, and the oil-associated gas leaked from the wear gap will pollute the atmosphere; wear to a certain extent After that, crude oil and high-salinity surface water will leak to the ground, causing serious pollution of the surface environment. (2) The labor intensity of the work...

AI Technical Summary

Problems solved by technology

The problems of this kind of seal are mainly manifested in the following aspects: (1) Serious environmental pollution: "locking" seal will inevitably lead to wear of the packing ring, and the oil-associated gas leaked from the wear gap will pollute the atmosphere; wear to a certain extent After that, crude oil and high-salinity surface water will leak to the ground, causing serious pollution of the surface environment

(2) The labor intensity of the workers is high: In order to prevent the packing box from leaking, oil production workers must inspect the well site every day and tighten the packing gland; the service life of the packing is not long, and production must be stopped every 2 weeks to replace new packing; This daily operation is a huge burden for the workers, especially in the northern oilfields in winter, where field operations are carried out in a harsh environment of more than 20 degrees below zero, the degree of difficulty can be imagined

(3) Potential safety hazard: the gas overflowing from the packing box is natural gas, which poses a serious threat to the safety of surrounding workers

(4) Increased energy consumption: the polished rod is always in the state of being tightly held by the packing, which increases the movement resistance and thus increases the energy consumption of the pumping unit

(5) Waste of resources: After the packing is worn out, there is a gap between the packing and the polished rod, and the pressurized oil, gas, and water in the oil well continue to emerge and overflow from the gap, wasting precious resources

(6) Damage to the polished rod: the polished rod is always in a frictional state held tightly by the packing. Friction loss makes the polished rod change from thick to thin, and fatigue stress causes cracks inside the polished rod. The double effect greatly shortens the service life of the polished rod

(7) It is easy to cause partial friction of the sucker rod: since the polished rod is always in a state of rigid compression, when it moves away from the central axis of the oil well, it will drive the sucker rod below to move away from the central axis of the oil well, resulting in partial friction of the sucker rod , so as to increase the power consumption of the pumping unit, and it is easy to cause a broken rod accident, so that the oil well is forced to stop production

In order to solve the problem of eccentric wear of the polished rod, some people install a horizontally movable packing box on the polished rod sealing device to hold the polished rod tightly. The disadvantage is that manual translation is required, and the packing box cannot be deflected along with the offset of the polished rod. The state of the packing box holding the polished rod increases the friction force and the energy consumption of the pumping unit increases accordingly

In order to solve the problem of straightening the offset of the polished rod, someone proposed to use the universal ball to adjust the offset of the polished rod, but the universal ball can only adjust the inclination of the polished rod, but cannot adjust the translation of the polished rod, and the translation of the polished rod is common in practical applications. The problem

In order to solve the problem of eccentric wear of the polished rod, someone designed a follow-up device for the polished rod, but at the same time, the sealing problem of the follow-up device occurred, because rainwater, sewage or sand and dust are easily infiltrated at the same time, which will not only make the polished rod and the sealing device of the polished rod The wear will increase, and it will cause corrosion to the polished rod and the polished rod sealing device, seriously affecting its service life

Images