CN107724987B

CN107724987B - Packing seal assembly

Info

Publication number: CN107724987B
Application number: CN201710978381.4A
Authority: CN
Inventors: 崔忠宝; 崔忠骏; 王学时
Original assignee: Tianjin Baojun Technology Co ltd
Current assignee: Tianjin Baojun Technology Co ltd
Priority date: 2017-10-18
Filing date: 2017-10-18
Publication date: 2024-03-19
Anticipated expiration: 2037-10-18
Also published as: CN107724987A

Abstract

The invention provides a packing sealing assembly, which comprises a packing assembly, wherein the packing assembly comprises a plurality of bowl-shaped sealing bodies, a sealing groove is in a circular arc structure, and a joint of the sealing groove and the surface of the sealing body adopts a fillet transition; the upper part of each sealing body is provided with a conical opening, the lower part of each sealing body is provided with a cylindrical opening serving as a shaft hole, a boss is formed at the joint of the cylindrical opening and the conical opening, and a compression pad is arranged on the upper surface of the boss; a first sealing piece is arranged between every two sealing bodies. The compaction pad adopts a metal pad, and the upper surface and the lower surface of the compaction pad are both planes. The invention provides a well head device, which is characterized in that a well head device is provided with a plurality of sealing bodies, wherein the sealing bodies are combined to form a well head device, a second sealing piece with a U-shaped opening is used as a main seal for sealing a polished rod, the polished rod is not required to be tightly attached to the second seal during assembly, and a pressing pad is pressed down by a pressing plate and the like after the polished rod is assembled, so that the second sealing piece is extruded to form reliable sealing.

Description

Packing seal assembly

Technical Field

The invention belongs to the technical field of oilfield wellhead sealing devices, and particularly relates to a packing sealing assembly.

Background

In the production process of oil wells, the rubber packing is widely used as a sealing material in the on-site wellhead sealing material, and horizontal offset and angular offset are generated between the polished rod and the wellhead due to the reasons of reciprocating motion of the polished rod, sinking of a pumping unit foundation, inaccurate installation position of the pumping unit and the like, so that wellhead eccentric wear, short service life of packing, wellhead oil leakage and the like are caused. The wellhead sealing packing is frequently worn along with the prolongation of the exploitation time, the temperature and viscosity change of the oil pumping well exploitation liquid, the oil well equipment and the like, the inner diameter of the wellhead sealing packing is increased after the wellhead sealing packing is worn, the sealing phenomenon cannot be achieved, the leakage phenomenon is serious day by day, and the wellhead sealing device is almost detached and can be replaced every time the wellhead sealing packing is replaced, so that the production efficiency is greatly influenced.

Disclosure of Invention

The present invention is directed to overcoming the above-mentioned drawbacks of the prior art, and providing a packing assembly.

In order to achieve the above purpose, the technical scheme of the invention is realized as follows:

the packing sealing assembly comprises a packing assembly with a cone-shaped structure as a whole, wherein the packing assembly comprises a plurality of bowl-shaped sealing bodies which are stacked, the upper part of each sealing body is provided with a cone-shaped opening, the lower part of each sealing body is provided with a cylindrical opening serving as a shaft hole, a boss is formed at the joint of the cylindrical opening and the cone-shaped opening, and a compression pad is arranged on the upper surface of the boss; a first sealing element is arranged between every two sealing bodies; and a mounting groove is formed in the inner wall of the cylindrical opening of each sealing body, and a second sealing piece is fixed in the mounting groove.

Further, the pressing pad is a metal pad, and the upper surface and the lower surface of the pressing pad are both planes.

Further, the cylindrical openings in each of the seal bodies are uniform in size.

Further, the first sealing piece adopts a sealing ring, and sealing grooves for installing the sealing ring are formed in the lower surface of the sealing body above and the upper surface of the sealing body below.

Further, the sealing groove is in a circular arc structure, and a fillet transition is adopted at the joint of the sealing groove and the surface of the sealing body.

Further, the second sealing member is of a U-shaped structure as a whole, and O-shaped rings are arranged on the outer edges of the groove walls on the two sides of the second sealing member towards the center side of the second sealing member.

Further, the O-ring is flush mounted on the second seal.

Further, the O-ring protrudes 0.25-0.5mm above the plane of the seal.

Further, the length value of the groove wall of the second sealing piece, which is positioned above, is 3-5mm larger than that of the groove wall of the second sealing piece, which is positioned below.

Compared with the prior art, the invention has the following advantages:

the invention has compact structure and good sealing effect. The packing is formed by several sealing body combination, is equipped with the first sealing member that is used for keeping sealed between individual sealing body, still is equipped with the second sealing member that is used for sealing up wellhead assembly polished rod on each sealing body, and whole sealing reliability is high, and the second sealing member has the compensation function, can make its cell wall move down through compressing tightly after wearing and tearing, still realizes splendid leakproofness, sealing member long service life has effectively guaranteed the operating efficiency.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and do not constitute an undue limitation on the invention. In the drawings:

FIG. 1 is a schematic diagram of the structure of the present invention;

FIG. 2 is a schematic view of a seal body according to the present invention;

fig. 3 is a schematic view of the structure of the second seal member in the present invention.

Reference numerals illustrate:

1-a sealing body; 2-a conical mouth; 3-a cylindrical port; 4-a boss; 5-a compression pad; 6-a first seal; 7-a mounting groove; 8-a second seal; 9-sealing the groove; 10-fillets; an 11-O-shaped ring; 12-upper groove wall; 13-lower groove wall.

Detailed Description

It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.

In the description of the invention, it should be understood that the terms "center," "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships that are based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the invention and simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be configured and operate in a particular orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", etc. may explicitly or implicitly include one or more such feature. In the description of the invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the creation of the present invention can be understood by those of ordinary skill in the art in a specific case.

The invention will be described in detail below with reference to the drawings in connection with embodiments.

1-3, a packing seal assembly comprises a packing assembly with a cone-shaped structure as a whole, wherein the packing assembly comprises a plurality of bowl-shaped seal bodies 1 which are stacked, the upper part of each seal body is provided with a cone-shaped opening 2, the lower part of each seal body is provided with a cylindrical opening 3 serving as a shaft hole, a boss 4 is formed at the joint of the cylindrical opening 3 and the cone-shaped opening 2, the cylindrical openings of each seal body are part of the shaft hole, and the shaft holes matched with a wellhead polished rod are formed together; a pressing pad 5 is arranged on the upper surface of the boss 4; a first sealing piece 6 is arranged between every two sealing bodies; a mounting groove 7 is formed in the inner wall of the cylindrical opening of each sealing body, and a second sealing member 8 is fixed in the mounting groove 7, and the second sealing member is preferably a U-shaped rubber sealing member.

It should be noted that, each sealing body is from top to bottom stacked together in proper order, constitutes packing structure jointly, and the shape of each sealing body is the same, and the inside cylindrical mouth size of sealing body is also the same.

In order to enable better packing compaction by means of a platen or the like of the wellhead seal, in an alternative embodiment, the packing 5 is a metal pad with planar upper and lower surfaces. When structural members such as a pressure plate of the wellhead sealing device are pressed on the pressing pad, the pressing pad uniformly distributes acting force of the pressure plate on the sealing body, so that the sealing bodies are uniformly loaded at all positions in the circumferential direction, and the sealing performance among all the sealing bodies is greatly improved.

Simultaneously, the second sealing element is uniformly pressed, the U-shaped opening of the second sealing element is narrowed, and the outer edges of the two groove walls can always prop against the polish rod of the wellhead device, so that reliable sealing is formed. The second sealing piece with the U-shaped opening is adopted as the main seal of the sealing polish rod, so that the difficulty of wellhead installation is reduced, the polish rod does not need to be tightly attached to the second seal during assembly, after the polish rod is assembled, the pressing pad is pressed down through the pressing plate and the like, the second sealing piece is extruded, and the outer edges of the upper groove wall and the lower groove wall of the second sealing piece can form reliable sealing with the polish rod.

The cylindrical openings 3 in the sealing bodies 1 are identical in size, and the cylindrical openings 3 in the sealing bodies are identical in size and are fully matched with the outer diameter of a polish rod to form reliable sealing.

The first sealing member 6 is a sealing ring, and a sealing groove 9 for installing the sealing ring is provided on the lower surface of the upper sealing body and the upper surface of the lower sealing body. Typically, the seal groove 9 has a circular arc structure, and a rounded corner 10 is adopted at the junction between the seal groove 9 and the surface of the seal body.

Because the circular arc-shaped sealing groove is adopted, compared with the traditional rectangular sealing groove, the sealing ring can be more ensured to be tightly pressed between the upper sealing body and the lower sealing body, and the design calculation of the compression amount of the sealing ring and the control of the compression amount can be facilitated when engineering design is carried out. And the joint of the sealing groove and the surface of the sealing body adopts the transition of a circular angle, so that the sealing ring can be prevented from being damaged by sharp corner damage.

It should be noted that the depth of the sealing groove is required to be less than 1/2 of the diameter of the sealing ring so as to ensure that the sealing ring deforms after being extruded between the upper sealing body and the lower sealing body to form a reliable seal, however, in order to ensure that the sealing ring can be firmly fixed, the depth of the sealing groove is generally greater than 1/3 of the diameter of the sealing ring, that is, the depth of the sealing groove is 1/3-1/2 of the diameter of the sealing ring.

The second sealing member 8 has a U-shaped structure as a whole, and O-rings 11 are mounted on the outer edges of both side walls of the second sealing member facing the center side of the second sealing member. Typically, an O-ring 11 is mounted flush on the second seal.

The O-ring 11 protrudes 0.25-0.5mm above the seal plane. Even the optical rod is worn on the sealing element, the O-shaped ring is damaged, the O-shaped ring is replaced, the cost is very low, and the sealing effect is very good.

The length of the groove wall of the second sealing element above is 3-5mm larger than that of the groove wall below. The upper groove wall of the upper second seal (designated as upper groove wall 12 in fig. 3) has a length value of 3-5mm greater toward the center of the circle than the lower groove wall (designated as lower groove wall 13 in fig. 3). The cell wall of upside receives the extrusion and moves down, and its sealed face can hug closely the polished rod, guarantees the leakproofness, even because long-time use, or loading and unloading adjustment take place certain wearing and tearing on the cell wall of U type recess department, through compressing tightly boss 4, second sealing member U type opening reduces, and the cell wall of top moves down, can also guarantee sealed face and water pipe closely laminating, can not produce any influence to the leakproofness. The sealing element has long service life, even can realize repeated use, and is energy-saving and environment-friendly.

The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A packing seal assembly, characterized in that: the packing assembly comprises a plurality of bowl-shaped sealing bodies which are stacked, wherein the upper part of each sealing body is provided with a conical opening, the lower part of each sealing body is provided with a cylindrical opening serving as a shaft hole, a boss is formed at the joint of the cylindrical opening and the conical opening, and a compression pad is arranged on the upper surface of the boss; a first sealing element is arranged between every two sealing bodies; a mounting groove is formed in the inner wall of the cylindrical opening of each sealing body, and a second sealing element is fixed in the mounting groove; the compaction pad is a metal pad, and the upper surface and the lower surface of the compaction pad are both planes; the cylindrical openings inside the sealing bodies are uniform in size;

the first sealing piece adopts a sealing ring, and sealing grooves for installing the sealing ring are arranged on the lower surface of the upper sealing body and the upper surface of the lower sealing body;

the sealing groove is in a circular arc structure, and a fillet transition is adopted at the joint of the sealing groove and the surface of the sealing body;

the second sealing piece is of a U-shaped structure as a whole, and O-shaped rings are arranged on the outer edges of the groove walls on two sides of the U-shaped structure towards one side of the center;

the O-shaped ring is embedded on the second sealing piece;

the length value of the groove wall of the second sealing piece, which is positioned above, is 3-5mm larger than that of the groove wall of the second sealing piece, which is positioned below.

2. A packing seal assembly according to claim 1, wherein: the O-shaped ring protrudes 0.25-0.5mm above the plane of the sealing element.