Pipeline joint sealing structure

Abstract

The utility model relates to a pipeline joint sealing structure, belongs to the technical field of sealing, and solves the problem of failure of the sealing structure caused by micro deformation of a sealing gasket in a high-temperature and high-pressure environment in the prior art. The connecting structure comprises a first connecting piece, a second connecting piece and a sealing gasket, the first connecting piece, the second connecting piece and the sealing washer have the same central axis; the first connecting piece has an inner conical surface; the second connecting piece has an outer conical surface; included angles between the inner conical surface and the central axis and between the outer conical surface and the central axis are A; the sealing washer is provided with a first conical surface and a second conical surface; the included angle between the first conical surface and the central axis and the second conical surface is B; the first conical surface is contacted with the inner conical surface, and the second conical surface is contacted with the outer conical surface; before sealing, B is less than A; after sealing, B is equal to A. The reliability of the sealing structure at high temperature and high pressure can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to sealing technical field especially relates to a pipeline joint sealing structure. BACKGROUND

[0002] At present, the sealing structure of metal plane washer extrusion sealing is generally used in the sealing structure of high temperature and high pressure (temperature is higher than 200 DEG C, pressure is higher than 0.8MPa) pipeline joint. But in high temperature and high pressure environment, the pipeline joint is susceptible to temperature and pressure and appears micro deformation (axial deformation is less than 0.2mm), which leads to the gap at the sealing, thereby affecting the sealing performance of the pipeline joint, and causing the internal medium leakage of the pipeline. SUMMARY

[0003] In view of the above analysis, the utility model embodiment aims at providing a pipeline joint sealing structure to solve the problem of micro deformation of sealing washer in high temperature and high pressure environment in prior art, leading to the failure of sealing structure.

[0004] The utility model discloses a pipeline joint sealing structure, which is characterized by the following technical solutions:

[0005] A pipeline joint sealing structure, comprising a first connecting piece, a second connecting piece and a sealing washer, wherein the first connecting piece, the second connecting piece and the sealing washer have the same central axis;

[0006] The first connecting piece has an inner conical surface, the second connecting piece has an outer conical surface, and the included angle between the inner conical surface, the outer conical surface and the central axis is A;

[0007] The sealing washer has a first conical surface and a second conical surface, and the included angle between the first conical surface, the second conical surface and the central axis is B; the first conical surface is in contact with the inner conical surface, and the second conical surface is in contact with the outer conical surface;

[0008] Before sealing, B

[0009] Further, the first connecting piece has a first inner circular surface, the second connecting piece has a first outer circular surface, the sealing washer further has a first circular surface and a second circular surface, and the diameter of the first circular surface is greater than the diameter of the second circular surface.

[0010] Further, the diameter of the second circular surface is the same as the diameter of the first outer circular surface, and the second circular surface is in abutment with the first outer circular surface to form a first sealing structure after sealing.

[0011] Further, the diameter of the first circular surface is the same as the diameter of the first inner circular surface, and the first circular surface is in abutment with the first inner circular surface to form a second sealing structure after sealing.

[0012] Further, before sealing, the A and the B satisfy the condition:

[0013] 60°≤A≤80°, 50°≤B≤70°.

[0014] Further, before sealing, the A and the B satisfy the condition: 10°≤A-B≤30°.

[0015] Further, further comprising a pressing member; the pressing member is arranged outside the first connecting member and the second connecting member, and the pressing member is used for pressing the connecting position of the first connecting member and the second connecting member.

[0016] Further, the first connecting member further has a second inner circular surface; and the second connecting member further has a second outer circular surface.

[0017] Further, the diameter of the second inner circular surface is same as the diameter of the first outer circular surface; and the diameter of the second outer circular surface is same as the diameter of the first inner circular surface.

[0018] Further, when sealing, the second connecting member extends into the first connecting member; the first outer circular surface is attached to the second inner circular surface; and the second outer circular surface is attached to the first inner circular surface.

[0019] Compared with the prior art, the utility model can realize at least one of the following beneficial effects:

[0020] (1) compared with the metal flat gasket extrusion sealing and ball taper contact sealing commonly used in the high-pressure pipeline connection in the prior art, the utility model adopts the sealing gasket with the taper structure, when extrusion sealing, the taper surface of the taper structure bears the force in two directions of the axial force and the radial force, on the one hand, the same as the flat gasket, the axial extrusion force is used for sealing in the axial direction, on the other hand, the radial force is used for sealing the gasket and the connecting member in the radial direction, and the sealing effect is enhanced.

[0021] The sealing gasket with the taper surface in the prior art has the same structure with the taper groove, when sealing, the whole taper surface of the gasket can be tightly attached to the taper surface of the taper groove, generates less radial force, cannot make the gasket generate enough deformation in the radial direction, and then cannot generate enough sealing pressure, so that the small gap under high temperature and high pressure makes the sealing invalid.The taper of the taper surface of the sealing gasket in the utility model is less than the taper of the taper groove, when sealing, the two ends of the sealing gasket are first contacted with the taper groove, gradually generate deformation through the extrusion force, and fill the four surfaces of the taper groove, and the extrusion force is maximum at the two ends when deforming.

[0022] (2) Since the diameter of the first circular surface is the same as the diameter of the first outer circular surface, and the diameter of the second circular surface is the same as the diameter of the first inner circular surface, the two ends of the sealing washer are attached to the first outer circular surface and the first inner circular surface, the radial deformation is limited by the first outer circular surface and the first inner circular surface to generate a radial extrusion force, a first sealing structure is formed on the first outer circular surface, and a second sealing structure is formed on the first inner circular surface. Therefore, the utility model has a double sealing structure, even if a micro gap is generated on the end surface under high temperature and high pressure, it can still rely on extrusion deformation to seal, improve the reliability of the sealing, especially in some equipment connections with vibration and slight connector deformation, the risk of leakage can be effectively reduced.

[0023] (3) Considering that the included angle B between the first tapered surface and the second tapered surface in the sealing washer and the center axis is less than 50°, it is difficult to compress; when B is greater than 70°, the sealing washer is prone to plastic deformation after sealing, which affects the sealing effect, therefore, the utility model sets 50°≤B≤70°; because the deformation amount of the sealing washer is too small, it cannot form sufficient sealing pressure; the deformation amount of the sealing washer is too large, which forms plastic deformation and affects the sealing effect, and sets 10°≤A-B≤30°. The included angle between the inner tapered surface and the outer tapered surface and the center axis is 60°≤A≤80°.

[0024] (4) In the utility model, the pressing part is applied to the first connector and the second connector in the axial extrusion force, so that the first connector and the second connector are tightly connected, and the sealing effect is realized.

[0025] In the utility model, the above technical solutions can be combined with each other to realize more preferred combination schemes. Other features and advantages of the utility model will be described in the following content, and some advantages can become apparent from the description or can be understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained through the content specially pointed out in the text and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0026] The drawings are only used for the purpose of illustrating specific embodiments and are not considered as limiting the utility model, and the same reference signs represent the same parts throughout the drawings.

[0027] Figure 1 It is a structure schematic view of the sealing structure of the specific embodiment;

[0028] Figure 2 It is an enlarged structure schematic view of the sealing washer connection of the specific embodiment;

[0029] Figure 3 It is a structure schematic view of the first connector of the specific embodiment;

[0030] Figure 4A structure schematic view of the second connecting piece of the specific embodiment;

[0031] Figure 5 A structure schematic view of the sealing gasket of the specific embodiment;

[0032] Figure 6 A structure schematic view before sealing of the specific embodiment.

[0033] Reference signs:

[0034] 1 - first connecting piece, 101 - first inner circular surface, 102 - inner tapered surface, 103 - second inner circular surface, 2 - second connecting piece, 201 - first outer circular surface, 202 - outer tapered surface, 203 - second outer circular surface, 3 - sealing gasket, 301 - first circular surface, 302 - second circular surface, 303 - first tapered surface, 304 - second tapered surface, 4 - pressing piece. DETAILED DESCRIPTION

[0035] The preferred embodiments of the utility model will be described in detail below in combination with the drawings, wherein the drawings form a part of the utility model, and are used together with the embodiments of the utility model to explain the principles of the utility model, and are not used to limit the scope of the utility model.

[0036] One specific embodiment of the utility model, as shown in Figure 1 and Figure 2 Disclosed is a pipeline joint sealing structure, comprising a first connecting piece 1, a second connecting piece 2 and a sealing gasket 3.

[0037] The first connecting piece 1, the second connecting piece 2 and the sealing gasket 3 are coaxially arranged and have the same central axis.

[0038] As shown in Figure 3 The first connecting piece 1 has an inner tapered surface 102 and a first inner circular surface 101; the included angle between the inner tapered surface 102 and the central axis is A.

[0039] As shown in Figure 4 The second connecting piece 2 has an outer tapered surface 202 and a first outer circular surface 201; the taper of the outer tapered surface 202 is the same as that of the inner tapered surface 102, and the included angle between the outer tapered surface 202 and the central axis is A.

[0040] As shown in Figure 5 The sealing gasket 3 is sleeved on the first outer circular surface 201 of the second connecting piece 2; the sealing gasket 3 has a first tapered surface 303 and a second tapered surface 304; the included angle between the first tapered surface 303 and the central axis and the included angle between the second tapered surface 304 and the central axis are both B.

[0041] When sealed, the inner tapered surface 102 of the first connecting piece 1 and the first inner circular surface 101, the outer tapered surface 202 of the second connecting piece 2 and the first outer circular surface 201 form a containing cavity for containing the sealing gasket 3. At this time, the first tapered surface 303 is in contact with the inner tapered surface 102 of the first connecting piece 1, and the second tapered surface 304 is in contact with the outer tapered surface 202 of the second connecting piece 2.

[0042] Compared with the metal flat gasket commonly used in the prior art for extrusion sealing of high-pressure pipeline connections, the sealing gasket 3 of the present embodiment adopts a tapered structure. When extrusion sealed, the tapered surface of the tapered structure bears axial force and radial force in two directions. On the one hand, it is sealed in the axial direction by axial extrusion force, like a flat gasket. On the other hand, it is sealed in the radial direction by radial force, thereby enhancing the sealing effect.

[0043] The sealing gasket 3 also has a first circular surface 301 and a second circular surface 302. The diameter of the first circular surface 301 is smaller than the diameter of the second circular surface 302. Further, the diameter of the first circular surface 301 is the same as the diameter of the first outer circular surface 201, and the diameter of the second circular surface 302 is the same as the diameter of the first inner circular surface 201. The two ends of the sealing gasket 3 are in close contact with the first outer circular surface and the first inner circular surface.

[0044] Considering that when the included angle B between the first tapered surface 303 and the second tapered surface 304 of the sealing gasket 3 and the central axis is less than 50°, it is difficult to compress; and when B is greater than 70°, the sealing gasket is prone to plastic deformation after sealing, affecting the sealing effect, 50°≤B≤70° is set. In the present embodiment, the included angle B between the first tapered surface 303 and the second tapered surface 304 and the central axis is 70°.

[0045] In order to make the sealing gasket 3 produce axial deformation and larger radial deformation when being compressed and sealed to produce extrusion sealing, B≠A before sealing. However, since B>A, due to the pressure difference between the high pressure and the low pressure at the two ends of the joint, the low pressure end does not have enough support, and the pressure difference will cause a gap in the radial sealing surface, causing the sealing to fail. Therefore, it is not enough to rely on the elastic deformation of the gasket to generate enough sealing pressure in the radial direction, so B

[0046] Further, since the deformation amount of the sealing gasket 3 is too small, it cannot form enough sealing pressure; and the deformation amount of the sealing gasket 3 is too large, forming plastic deformation and affecting the sealing effect, 10°≤A-B≤30° is set. The included angle between the inner tapered surface 102 and the outer tapered surface 202 and the central axis is 60°≤A≤80°. In the present embodiment, the included angle between the inner tapered surface 102 and the outer tapered surface 202 and the central axis is set to 80°.

[0047] The prior art sealing gasket 3 has a conical surface structure identical to that of the conical groove, and the entire conical surface of the gasket can be tightly fitted with the conical surface of the conical groove during sealing. Since the included angle between the conical surface and the central axis is large, a small radial force is generated, the gasket cannot be deformed enough, and thus cannot generate sufficient sealing pressure, resulting in a small gap under high temperature and high pressure, which causes the sealing to fail. In the present embodiment, the included angle between the conical surface of the sealing gasket 3 and the central axis is different from the included angle between the conical groove and the central axis. During sealing, the two ends of the sealing gasket 3 first contact the conical groove, gradually deforming under the extrusion force, and gradually filling the four surfaces of the conical groove. The extrusion force is the largest at the two ends during deformation. Since the two ends of the sealing gasket 3 in the present embodiment are in contact with the first outer circular surface and the first inner circular surface, the radial deformation is limited by the first outer circular surface 201 and the first inner circular surface 101 to generate a large radial extrusion force, forming a first sealing structure on the first outer circular surface 201 and a second sealing structure on the first inner circular surface 101. Therefore, the present embodiment has a double sealing structure. Even if a small gap is generated at the end surface under high temperature and high pressure, it can still be sealed by extrusion deformation, improving the reliability of the sealing, and effectively reducing the risk of leakage, especially in some equipment connections with vibration and slight connector deformation.

[0048] The first connector 1 also has a second inner circular surface 103, and the second connector 2 also has a second outer circular surface 203. The diameter of the second inner circular surface 103 is the same as that of the first outer circular surface 201, and the diameter of the second outer circular surface 203 is the same as that of the first inner circular surface 101. During sealing, the second connector 2 extends into the first connector 1, at which time the first outer circular surface 201 is in contact with the second inner circular surface 103, and the second outer circular surface 203 is in contact with the first inner circular surface 101.

[0049] Further, a pressing member 4 is also included. The pressing member 4 is arranged outside the first connector 1 and the second connector 2, and is used to press the first connector 1 and the second connector 2 tightly by pressure, so that the sealing gasket 3 is tightly fitted.

[0050] As shown in Figure 6 the use, the sealing gasket 3 is sleeved on the first outer circular surface 201 of the second connector 2. Since the diameter of the first circular surface 301 of the sealing gasket 3 is the same as that of the first outer circular surface 201, the second circular surface 302 of the sealing gasket 3 is in contact with the first outer circular surface 201 of the second connector 2.

[0051] When the angle between the second conical surface 304 of the sealing gasket 3 and the central axis is less than the angle between the outer conical surface 202 of the second connector 2 and the central axis, the upper end of the second conical surface 304 contacts the upper end of the outer conical surface 202. The second connector 2 is then connected to the first connector 1, with the connecting end of the second connector 2 extending into the interior of the first connector 1. At this time, the lower end of the first conical surface 303 of the sealing gasket 3 contacts the lower end of the inner conical surface 102. The diameter of the second circular surface 302 of the sealing gasket 3 is equal to the diameter of the first inner circular surface 101 of the first connector 1, so the second circular surface 302 of the sealing gasket 3 fits snugly against the first inner circular surface 101 of the first connector 1.

[0052] A clamping member 4 is fitted onto the outside of the first connecting member 1 and the second connecting member 2. Exemplarily, in this embodiment, the clamping member 4 has an internal thread, and the first connecting member 1 has an external thread. The internal thread of the clamping member 4 can be screwed into the external thread of the first connecting member 1. Simultaneously, the second connecting member 2 has a flange on its exterior. One end of the flange is an outer conical surface 202, and the other end is a plane perpendicular to its axis. The outer conical surface 202 contacts the second conical surface 304 of the sealing washer 3, and the plane perpendicular to its axis is used to engage the clamping member 4.

[0053] The clamping member 4 engages with the end of the flange of the second connecting member 2 and simultaneously screws into the external thread of the first connecting member 1, thus pressing the connection between the first connecting member 1 and the second connecting member 2 tightly. At this time, the clamping member 4 applies axial compressive force to the first connecting member 1 and the second connecting member 2, making the first connecting member 1 and the second connecting member 2 tightly connected. The axial compressive force is transmitted to the end face of the sealing gasket 3 through the first connecting member 1 and the second connecting member 2, generating a compressive component force perpendicular to the conical surface of the sealing gasket 3, causing the sealing gasket 3 to deform in the thickness direction and fill the gap between the sealing gasket 3 and the first connecting member 1 and the second connecting member 2. Under the action of axial force, the sealing gasket 3 first deforms at the contact point, that is, at the upper and lower ends of the sealing gasket 3. Since the length of the sealing gasket 3 is the same as the length of the cavity, the first inner circular surface 101 and the first outer circular surface 201 prevent the sealing gasket 3 from deforming in the longitudinal direction, which is converted into the radial extrusion force of the sealing gasket 3 on the first inner circular surface 101 and the first outer circular surface 201. As a result, the two radial ends of the sealing gasket 3 abut against the first inner circular surface 101 and the first outer circular surface 201 respectively, forming a double extrusion seal on the first inner circular surface 101 and the first outer circular surface 201, thereby improving the reliability of the sealing structure.

[0054] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A pipe joint seal structure, characterized by, The utility model provides a sealing structure of a first connecting piece (1), a second connecting piece (2) and a sealing washer (3), which comprises the first connecting piece (1), the second connecting piece (2) and the sealing washer (3), wherein the first connecting piece (1), the second connecting piece (2) and the sealing washer (3) have the same central axis; The first connecting piece (1) has an inner taper surface (102), the second connecting piece (2) has an outer taper surface (202), and the inner taper surface (102) and the outer taper surface (202) have an angle A with the central axis; The sealing washer (3) has a first taper surface (303) and a second taper surface (304), the first taper surface (303) and the second taper surface (304) have an angle B with the central axis, the first taper surface (303) is in contact with the inner taper surface (102), and the second taper surface (304) is in contact with the outer taper surface (202); Before sealing, B < A; and after sealing, B = A.

2. The pipe joint seal structure of claim 1, wherein, The first connecting piece (1) has a first inner circular surface (101), the second connecting piece (2) has a first outer circular surface (201), the sealing washer (3) further has a first circular surface (301) and a second circular surface (302), and the diameter of the first circular surface (301) is greater than the diameter of the second circular surface (302).

3. The pipe joint seal structure of claim 2, wherein, The diameter of the second circular surface (302) is the same as the diameter of the first outer circular surface (201), and the second circular surface (302) is in abutment with the first outer circular surface (201) to form a first sealing structure after sealing.

4. The pipe joint seal structure of claim 2, wherein, The diameter of the first circular surface (301) is the same as the diameter of the first inner circular surface (101), and the first circular surface (301) is in abutment with the first inner circular surface (101) to form a second sealing structure after sealing.

5. The pipe joint seal structure of claim 1, wherein, Before sealing, the A and the B satisfy the condition: 60° ≤ A ≤ 80°, and 50° ≤ B ≤ 70°.

6. The pipe joint seal structure of claim 5, wherein, Before sealing, the A and the B satisfy the condition: 10° ≤ A - B ≤ 30°.

7. The pipe joint seal structure of claim 1, wherein, The utility model further comprises a pressing piece (4), the pressing piece (4) is arranged outside the first connecting piece (1) and the second connecting piece (2), and the pressing piece (4) is used for pressing the connecting position of the first connecting piece (1) and the second connecting piece (2).

8. The pipe joint seal structure of claim 2, wherein, The first connecting piece (1) further has a second inner circular surface (103), and the second connecting piece (2) further has a second outer circular surface (203).

9. The pipe joint seal structure of claim 8, wherein, The diameter of the second inner circular surface (103) is the same as the diameter of the first outer circular surface (201), and the diameter of the second outer circular surface (203) is the same as the diameter of the first inner circular surface (101).

10. The pipe joint seal structure of claim 9, wherein, During sealing, the second connecting piece (2) extends into the first connecting piece (1), the first outer circular surface (201) is in abutment with the second inner circular surface (103), and the second outer circular surface (203) is in abutment with the first inner circular surface (101).

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