CN116905980A - Axial, transverse and torsional force damper - Google Patents

Abstract

The present invention is a downhole tool for inhibiting vibratory forces, lateral forces, compressive forces and tensile forces exerted on a sensor device within a drill pipe. The tool mainly comprises an upper sliding shaft, a lower sliding shaft, a compression shell, a torsion sleeve, an O-shaped sealing ring, a first spring assembly, a second spring assembly, a spring upper buckle, a spring lower buckle, a pressure compensator, a dust ring, an intermediate baffle plate, a pin and a stop ring. The sliding shaft can slide up and down in a closed space formed by the compression shell and the torsion shell; the first spring assembly is restrained by the washer providing axial damping between the compression housing and the sliding shaft; the second spring assembly is restrained at the lower part of the compression shell by the upper spring buckle and the lower spring buckle, and axial damping is provided between the compression shell and the sliding shaft; the middle partition plate is used for connecting the compression shell and the torsion shell; the pin in the torsion housing provides torsional damping while providing axial sliding; the stop ring is used for restraining the torsion housing. The dust ring contains lubricating oil and is used for preventing dust from entering and affecting the service life of the whole tool; the pressure compensator greatly improves the sealing life and reduces the internal and external pressure differences, thereby allowing free sliding of the shaft.

Description

Axial, transverse and torsional force damper

Technical Field

The invention relates to an axial, transverse and torsional damper, belonging to the technical field of drilling tools for petroleum and natural gas exploitation.

Technical Field

In the oil and gas industry, particularly in the processes of directional drilling, measurement While Drilling (MWD), logging While Drilling (LWD), and Logging While Tripping (LWT), there is a need to protect downhole equipment from high impact downhole environments. In particular, since downhole measurement equipment installed in a drill string is mostly sensitive, it is desirable to protect the equipment from severe torsional, axial and lateral vibrations and shocks during up and down movements and rotations of the drill string in the well. Generally, such devices are designed to take these stress loads into account; but as with all other devices, the withstand capability of these devices is limited. For example, in special cases such as MMD and horizontal drilling, such techniques typically require or utilize a drill string stirring device to achieve the desired rate of penetration (ROP). Thus, as impact and vibration loads increase, the measurement device may be more susceptible to damage.

Furthermore, in the special case of horizontal drilling, severe torsional stresses may be imposed on the drill string due to friction of the long stationary drill pipe against the lower surface of the well. That is, during deviated section drilling, the drill string may "roll up" as it begins to rotate, and the friction of the drill string against the well must be overcome before the drill string rotates. In these cases, torsional vibrations are often massive when these frictional forces are overcome, which can place severe stresses on sensors located within the drill string. Thus, severe forces exerted on various devices often result in unexpected failure of the device. As drilling techniques and methods develop, the equipment may be subjected to greater stresses.

Various techniques have been developed in the past to address these problems, and although some of the techniques in the past have been partially effective in addressing some of the problems described above, there remains a need for techniques that effectively provide a unified solution to suppress axial vibration, lateral and torsional forces while also maintaining through hole pressure within the drill string.

Disclosure of Invention

It is an object of the present invention to provide a downhole vibration damper for addressing axial and torsional vibrations generated during drilling as the depth of an oil well increases.

In order to achieve the above purpose, the technical scheme adopted by the invention for solving the problem is as follows: a downhole tool is disclosed for inhibiting axial, lateral and torsional forces exerted on a sensor device within a drill pipe. The tool mainly comprises an upper sliding shaft, a lower sliding shaft, a compression shell, a torsion sleeve, an O-shaped sealing ring, a first spring assembly, a second spring assembly, a spring upper buckle, a spring lower buckle, a pressure compensator, a dust ring, an intermediate baffle plate, a pin and a stop ring.

The sliding shaft can slide up and down in a closed space formed by the compression shell and the torsion shell;

the torsion housing is used for providing torsion damping on the equipment, the torsion housing comprises an outer torsion housing and an inner torsion cylinder which can mutually axially move, the inner surface of the torsion sleeve comprises pin grooves for accommodating pins, the purpose of which is to connect the inner surface of the torsion sleeve and the outer surface of the lower sliding shaft by the pins so that the sliding shaft can move up and down in the compression housing and the torsion housing, and the pins in the torsion housing provide torsion damping at the same time as axial sliding;

the first spring assembly is restrained by a washer providing axial damping between the compression housing and the sliding shaft; the second spring assembly is restrained at the lower part of the compression shell by the upper spring buckle and the lower spring buckle, and axial damping is provided between the compression shell and the sliding shaft; wherein the spring assembly comprises one or more spring members, each spring member comprising an elastic ring which is elastically deformable to a compressed position; further comprising a first annular disk having a top surface and a central aperture and a second annular disk having a bottom surface and a central aperture, and an inner wall extending around the inner circumference of the first or second annular disk and an outer wall extending around the outer circumference of the first or second annular disk;

the top surface of the first annular disk faces the bottom surface of the second annular disk to align the holes of each annular disk and form a channel between the annular disks for movement of a spring member movable between: a balance position and a compression position;

the middle partition plate is used for connecting the compression shell and the torsion shell and forming a sealing structure of the whole damper;

the pressure compensator is used for balancing the pressure difference between the sealing piece and the external fluid when the external fluid enters the O-shaped ring to be pressurized through the through hole, so that the service life of the seal is greatly prolonged and the pressure applied by the sealed shaft is reduced;

the dust ring can effectively prevent the influence of slurry and other particles on the whole damper in the working process, and prolongs the service life of the whole part.

The invention has the advantages with the prior invention that:

the spring component replaces the traditional single spring, has the advantages of longer service life and larger damping, and can flexibly adjust the number of the spring components according to the actual condition of the site to adapt to the environment or the requirement of axial damping.

2 replacing the conventional pin assembly with a torsion sleeve, the inner and outer ring structure provides greater torsional damping with greater life and reliability

The full chamber is sealed and contains hydraulic fluid, providing good lubrication while also providing better damping against external pressure.

Drawings

FIG. 1 is a schematic view of the structure of the present invention

In the figure, 1-lower sliding shaft, 2-torsion housing, 3-compression housing, 4-upper sliding shaft, 5-upper intermediate space, 6,7,19-O-ring seal, 8-dust ring, 9-washer, 10-first set of annular spring outer ring, 11-first set of annular spring inner ring, 12-support ring, 13-snap-down, 14-second set of annular spring outer ring, 15-second set of annular spring inner ring, 16-snap-up, 17-intermediate spacer, 18-pressure compensator, 20-belleville spring, 21 torsion sleeve, 22-pin, 23-lower intermediate spacer, 24-snap ring, 25-pin slot, 26-elastic ring, 27-center hole, 28-groove, 29-through hole

FIG. 2 is a schematic view of a spring assembly

FIG. 3 is a schematic view of a spring member

FIG. 4 is a schematic view of a torsion sleeve

FIG. 5 is a schematic view of an upper sliding shaft

FIG. 6 is a schematic view of a lower sliding shaft

FIG. 7 is a schematic diagram of a pressure compensator

Detailed description of the preferred embodiments

The invention will be further described with reference to the accompanying drawings

As shown in fig. 1, the axial, transverse and torsional force damper is composed of a lower sliding shaft 1, a torsion housing 2, a compression housing 3, an upper sliding shaft 4, upper middle intervals 5,O, sealing rings 6,7 and 19, a dust ring 8, a gasket 9, a first group of annular spring outer rings 10, a first group of annular spring inner rings 11, a supporting ring 12, a spring lower buckle 13, a second group of annular spring outer rings 14, a second group of annular spring inner rings 15, a spring upper buckle 16, a middle partition 17, a pressure compensator 18, a disc spring 20, a torsion sleeve 21, pins 22, a lower middle partition 23 and a stop ring 24. The upper part of the tool is connected with the sensor, and the lower part of the tool is connected with the platform joint; the compression shell 3 and the torsion shell 2 form a closed space, and the upper sliding shaft 4 and the lower sliding shaft 1 slide up and down; a first spring assembly of a first set of annular spring outer rings 10 and a first set of annular spring inner rings 11, a second spring assembly of a second set of annular spring outer rings 14 and a second set of annular spring inner rings 15, all providing axial damping; the pin 22 in the torsion housing 2 engages in a groove on the sliding shaft, mainly providing torsion damping; wherein the lower sliding shaft 1, the upper sliding shaft 4, the compression housing 3, the intermediate partition 17 and the stop ring 24 are generally cylindrical, each having an internal through hole so that hydraulic oil can flow between the assembled structures.

First, a process of providing axial damping to the spring structure will be described. As shown in fig. 1, the first spring assembly is located in the chamber between the compression housing 3 and the upper sliding shaft 4 with its wellhead end abutting against the shoulder of the compression housing 3 and its bottom hole end abutting against the shoulder of the upper sliding shaft 4. A schematic of the structure of the spring assembly is shown in fig. 2, and a schematic of the structure of the spring member is shown in fig. 3. Wherein the spring assembly comprises one or more spring members, each spring member comprising an elastic ring 26 elastically deformable to a compressed position, a first annular disc having a top surface and a central aperture 27 and a second annular disc having a bottom surface and a central aperture, and an inner wall extending around the inner circumference of the first or second annular disc and an outer wall extending around the outer circumference of the first or second annular disc; wherein the top surface of the first annular disc faces the bottom surface of the second annular disc to align the apertures of each annular disc and form a channel between the annular discs for movement of a spring member movable between: an equilibrium position and a compressed position.

When an axial force is applied to the lower sliding shaft, the lower sliding shaft and the upper sliding shaft move telescopically within the compression housing. When a compressive force is received in the uphole direction to move the sliding shaft toward the uphole, this compresses the chamber as the shoulder surface on the upper sliding shaft moves, thereby compressing the first spring assembly to move it to the compressed position, providing axial damping. When the pressure is released, the first spring assembly springs back to its equilibrium position, biasing the entire damper toward its equilibrium position.

Once all of the spring members in the first spring assembly are fully in compression, the second stage of damping will be provided by the belleville spring 20 assembly at the end of the spring assembly. Each belleville spring assembly is comprised of a plurality of belleville spring members (commonly referred to as belleville washers). Belleville springs 20 are shaped like washers and have a conical or cup-shaped configuration. When an axial force is applied to the axial belleville springs, the springs will move from the conical or cup shape in the rest position to a substantially flat disc in the fully compressed position to provide damping. When the axial force is released, the belleville springs 20 spring to their equilibrium position.

At the same time, when the spring members of the first spring assembly are fully compressed, the sliding shaft will move sufficiently to allow the catch mechanism on the second spring assembly: i.e. the sprung snap and the sprung snap can engage with the compression housing and the lower sliding axle. Thus, further application of compressive force will cause the second spring assembly to engage the compression housing and lower slide shaft. Once engaged, the second spring will compress to provide additional axial damping as desired. When the pressure is released, the second spring assembly springs back to their equilibrium position and the catch structure is disengaged.

Next, the torsion sleeve 21 will be described. As shown in fig. 4, the torsion sleeve includes pin grooves on its inner surface for connecting the torsion sleeve inner surface and the lower sliding shaft outer surface with pins 22. The pin slots in the torsion sleeve 21 are similar to the pin slots contained within a typical pin housing sleeve. In other words, the pin slot is spaced about the inner surface of the torsion sleeve and is parallel to the axial direction of the torsion sleeve. The pin slot is slightly longer than the pin to allow axial movement of the lower sliding axle 1 relative to the torsion sleeve 21 and the pin 22. While the width of the pin slot is adjusted to closely receive the pin to prevent relative rotation thereof.

As described above, the lower sliding shaft 1 has a groove in which the pin 22 is contained. The recess may be sized to mate with the pin or may be slightly longer. The engagement of the pin in the pin slot and groove limits the rotational movement of the torsion barrel relative to the lower sliding axle while still allowing axial movement a distance. In addition, there is hydraulic oil retained around the pins in the pin slots, which can provide hydraulic damping during pin movement.

At the same time, one or more belleville springs 20 (also referred to as belleville washers) are located at the ports of the torsion sleeve so that axial displacement of the torsion sleeve 21 will act on these belleville springs 20. Thus, the torsional force exerted on the lower sliding axle will be damped by the axial movement of the torsion sleeve relative to the belleville springs.

The torque applied to the lower sliding axle will cause the torque sleeve to move axially through the axle engaged with the pin slot, but not rotate. A small amount of rotational movement (up to 5 degrees in a clockwise or counter-clockwise direction relative to the lower sliding axle) may still occur during this process. The rotational and axial movements are initially damped by the hydraulic oil around the pins, which provides more damping as the movement proceeds. Finally, further axial damping is provided by the belleville springs.

A pressure compensator is shown in fig. 7. The pressure compensator is positioned near the O-ring on the upper sliding shaft and is provided with a plurality of through holes in structure to balance the internal pressure and the external pressure. As described above, the unitary structure includes a plurality of apertures that allow external fluid access. The external fluid pressurizes the O-ring, and the fluid portion in the O-ring is then squeezed into the bore of the pressure compensator, balancing the internal and external pressures, greatly reducing the external fluid pressure. The pressure compensator greatly increases the seal life and reduces the force applied by the seal to the shaft, allowing it to move more freely.

Claims (8)

1. An axial, transverse and torsional damper comprises a lower sliding shaft (1), a torsion housing (2), a compression housing (3), an upper sliding shaft (4), an upper middle interval (5), O-shaped sealing rings (6) (7) (19), a dust ring (8), a gasket (9), a first group of annular spring outer rings (10), a first group of annular spring inner rings (11), a supporting ring (12), a spring lower buckle (13), a second group of annular spring outer rings (14), a second group of annular spring inner rings (15), a spring upper buckle (16), a middle baffle (17), a pressure compensator (18), a disc spring (20), a torsion sleeve (21), a pin (22), a lower middle baffle (23) and a stop ring (24). The upper part of the tool is connected with the sensor, and the lower part of the tool is connected with the platform joint; the compression shell (3) and the torsion shell (2) form a closed space, and the upper sliding shaft (4) and the lower sliding shaft (1) slide up and down; a first spring assembly consisting of a first set of annular spring outer rings (10) and a first set of annular spring inner rings (11) and a second spring assembly consisting of a second set of annular spring outer rings (14) and a second set of annular spring inner rings (15) provide axial resistance; the pin (22) in the torsion housing (2) engages in a groove on the sliding shaft, mainly providing torsional damping.

2. An axial, transverse and torsional force damper according to claim 1, characterized in that the first and second sets of spring assemblies provide axial damping of the shaft when it is subjected to tensile or compressive forces in the compression housing (3) and in the upper sliding shaft (4).

3. An axial, transverse and torsional damper according to claim 2, characterized in that the first and second sets of spring assemblies consist of a first set of annular spring outer rings (10), a first set of annular spring inner rings (11) and a second set of annular spring outer rings (14), a second set of annular spring inner rings (15) and respective elastic members.

4. An axial, transverse and torsional damper as defined in claim 1, characterized in that the torsion housing (2) comprises an outer torsion housing and an inner torsion housing having mating splines and grooves, the inner torsion housing being capable of helical and axial movement relative to the outer torsion housing when the inner torsion housing is subjected to torsional forces relative to the outer torsion housing.

5. An axial, transverse and torsional force damper as defined in claim 4, characterized in that said inner torsional shell (2) includes at least one longitudinal slot effective to receive said at least one pin (22).

6. An axial, transverse and torsional damper according to claim 1, characterized in that it comprises a first sealing between the torsion housing (2) and the lower sliding shaft (1) and a second sealing between the compression housing (3) and the upper sliding shaft.

7. An axial, transverse and torsional force damper according to claim 6, characterized in that it comprises a pressure compensator (18) for balancing the pressure outside the tool with the first and second sealing arrangements.

8. An axial, transverse and torsional damper according to claim 1, characterized in that it comprises a dust ring (8) connected to the sealing structure.