End face sealing structure for rotary compensator and rotary compensator

Abstract

The present invention relates to an end face sealing structure for a rotary compensator and a rotary compensator using the same. The end face sealing structure for the rotary compensator comprises an annular inner boss (10) arranged on the inner surface of an outer sleeve (6), a sealing filler (8) arranged between a sealing clamping flange (5) and the annular inner boss (10), a sealing pressure ring (7) arranged between the sealing clamping flange (5) and the sealing filler (8), the cross section of the sealing pressure ring (7) is concave, and the end of the sealing clamping flange (5) adjacent to the sealing filler (8) extends into the concave notch of the sealing pressure ring (7); an annular groove is formed on the side adjacent to the annular inner boss (10) and the sealing filler (8), and a sealing anti-pressure ring (9) is installed in the annular groove. The present invention can effectively delay the ablation amount of the sealing material at high temperature, reduce the loss of the sealing material in the assembly gap of the rotary compensator in the working state, and significantly improve the sealing effect.

Description

Technical Field

[0001] The invention relates to an end face sealing structure for a rotary compensator and the rotary compensator. Background Art

[0002] At present, rotary compensators are more and more widely used in thermal pipelines. Rotary compensators have many advantages such as high safety performance, convenient design, large compensation volume, high pipeline operation economy, and diversified installation methods and types. They have always been the first choice of design institutes and the preferred product of thermal power plants and other users. The main technical core of rotary compensators lies in sealing technology. Although people have been improving the sealing performance of rotary compensators, there is still a possibility of leakage during the operation of rotary compensators. The reasons are as follows:

[0003] 1. Ablation under high temperature and oxygen conditions.

[0004] The rotary compensator works under high temperature for a long time. The sealing material (graphite, etc.) will be ablated in high temperature and oxygen state, and its volume will be reduced due to contact with oxygen, thus causing leakage. Therefore, controlling the contact amount between the sealing packing and oxygen is one of the most important means to ensure long-term sealing.

[0005] 2. The packing is worn during operation.

[0006] The inner tube and outer tube of the rotary compensator cannot be absolutely smooth (i.e., the friction coefficient = 0). Therefore, the relative rotation of the inner tube and outer tube when the rotary compensator is working will cause wear of the packing. As a result, part of the sealing packing will appear in a state of fragments and powder, which is easy to leak from the assembly gap, resulting in a reduction in the volume of the packing in the sealing cavity and a decrease in the sealing compression force, thus causing leakage.

[0007] 3. Wear caused by oxidation of the sealing cavity surface.

[0008] After long-term use, the rotary compensator will be affected by adverse factors of the medium in the pipeline (such as chloride ions, humidity, and temperature), which will cause corrosion on the contact surface between the sealing cavity and the sealing material, forming unevenness. When the rotary compensator is in working condition, it is easy to cause wear of the packing, resulting in part of the sealing packing being in a state of fragments and powder, which is easy to lose from the assembly gap, resulting in a reduction in the volume of the packing in the sealing cavity and a decrease in the sealing compression force, thus causing leakage.

[0009] 4. Loss due to chemical reaction between sealing filler and medium (high temperature steam, high temperature hot water, etc.).

[0010] Because the medium will produce a chemical reaction with the sealing filler under high temperature (for example: C+H2O(high temperature)=CO+H2), the solid volume of the sealing filler will decrease, the sealing performance will decrease, and leakage will easily occur.

[0011] 5. The medium scours the sealing packing under high pressure.

[0012] Under working conditions, the medium in the rotary compensator with high temperature and high pressure can easily enter the sealing cavity from the assembly gap, exerting a strong impact on the sealing packing. After long-term use, the sealing packing will be damaged under the erosion of the medium with high temperature and high pressure, thus causing the sealing performance to deteriorate.

[0013] Therefore, further improving the sealing performance of the rotary compensator is a goal that technicians in this field strive for. Summary of the invention

[0014] In order to effectively delay the ablation of sealing material at high temperature and reduce the loss of sealing material in the assembly gap of the rotary compensator when the rotary compensator is in operation, the present invention proposes an end face sealing structure for a rotary compensator and a rotary compensator with better sealing performance.

[0015] The end face sealing structure for the rotary compensator of the present invention comprises an annular inner boss arranged on the inner surface of the outer sleeve, a sealing packing arranged between the sealing clamping flange and the annular inner boss, a sealing pressure ring arranged between the sealing clamping flange and the sealing packing, the sealing pressure ring has a concave cross section, and the end of the sealing clamping flange adjacent to the sealing packing extends into the concave notch of the sealing pressure ring. An annular groove is formed on the inner wall of the side adjacent to the annular inner boss and the sealing packing, and a sealing anti-pressure ring is installed in the aforementioned annular groove.

[0016] The rotary compensator described in the present invention adopts the aforementioned end face sealing structure, including an inner tube, an outer tube, a reducer, and a sealing compression flange. One end of the inner tube extends into the outer tube, and the sealing compression flange is mounted on the inner tube, and one end thereof extends into the outer tube. An annular inner boss is provided on the inner surface of the outer tube, and an annular outer boss is provided on the outer surface of the inner tube. A sealing filler is provided between the annular inner boss and the end of the sealing compression flange extending into the outer tube, and a sliding part or an end face seal is provided in the cavity formed between the annular outer boss and the annular inner boss. A sealing pressure ring is provided between the sealing compression flange and the sealing filler, and the cross-section of the sealing pressure ring is concave-shaped, and the end of the sealing compression flange adjacent to the sealing filler extends into the concave-shaped notch of the sealing pressure. An annular groove is provided on the inner wall of the side adjacent to the annular inner boss and the sealing filler, and a sealing anti-pressure ring is installed in the aforementioned annular groove.

[0017] In order to solve the potential safety hazard caused by welding the outer sleeve and the reducer, the outer sleeve and the reducer are integrally formed into an integrated structure.

[0018] In order to prevent the sealing packing from forming gaps due to normal wear during long-term use, thereby affecting the sealing performance of the entire rotary compensator, a sealing packing filling device is provided on the outer sleeve.

[0019] In order to prevent the product from dislocating in the opposite direction during the engineering installation process and to prevent the sliding parts or end face seals set between the inner and outer annular bosses from shifting, a limit block is set in the reducer.

[0020] The sliding member is a ball or a sliding ring.

[0021] Since the present invention provides a sealing pressure ring between the sealing compression flange and the sealing filler, the assembly gap between the flange and the outer sleeve and the inner tube is filled and reduced, thereby isolating or reducing the contact between the sealing filler and oxygen, thereby effectively delaying the ablation of the sealing filler graphite at high temperature, and also effectively reducing the loss of sealing material from the assembly gap when the rotary compensator is in working condition.

[0022] At the same time, the present invention further isolates or reduces the contact between air and the sealing filler by opening an annular groove on the inner wall of the annular inner boss adjacent to the sealing filler, installing a sealing pressure-resistant ring in the annular groove, and making the sealing pressure-resistant ring fit with the inner tube and fill the assembly gap between the inner tube and the outer tube, thereby effectively delaying the ablation of the sealing filler at high temperature, reducing the loss of sealing material from the assembly gap when the rotary compensator is in working condition, and reducing the scouring of the sealing filler by the medium driven by the pressure in the tube, thereby further ensuring the sealing performance of the rotary compensator.

[0023] Since the present invention adopts the above double sealing structure, no matter what installation method the rotary compensator adopts (the inner tube faces upward or downward), the sealing pressure ring and the sealing anti-pressure ring can firmly lock the sealing filler, preventing the outer layer of sealing filler oxidized by contact with air from being lost from the original assembly gap due to gravity, thereby effectively preventing the volume of the sealing cavity filler from decreasing, ensuring that the sealing performance of the product does not decrease, and avoiding the occurrence of leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of Example 1 of the present invention.

[0025] Figure 2 for Figure 1 A partial enlarged view of .

[0026] Figure 3 This is a schematic diagram of the structure of Example 2 of the present invention.

[0027] Figure 1-Figure 3 Among them, 1 is an inner tube, 2 is a stud, 3 is a nut, 4 is a gasket, 5 is a sealing clamping flange, 6 is an outer sleeve, 7 is a sealing pressure ring, 8 is a sealing filler, 9 is a sealing pressure ring, 10 is an annular inner boss, 11 is a sliding part, 12 is an annular outer boss, 13 is a limit block, 14 is a reducer, and 15 is a filling device. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, so that the above-mentioned and other objects, features and advantages of the present invention will be clearer. The accompanying drawings are not deliberately drawn to scale, and the focus is on illustrating the main purpose of the embodiments.

[0029] Example 1

[0030] like Figure 1 , Figure 2 As shown, the rotary compensator of this embodiment comprises an inner tube 1, an outer tube 6, a reducer 14, and a sealing and pressing flange 3. One end of the inner tube 1 extends into the outer tube 4. The sealing and pressing flange 3 is sleeved on the inner tube 1, and one end of the inner tube 1 extends into the outer tube 6. The two are connected by screws 2, nuts 3, and gaskets 4. An annular inner boss 10 is provided on the inner surface of the outer tube 6, and an annular outer boss 12 is provided on the outer surface of the inner tube 1. A sealing packing 8 is provided between the annular inner boss 10 and the end of the sealing and pressing flange 5 extending into the outer tube 6. A sliding member 11 is provided in the cavity formed between the annular outer boss and the annular inner boss. A sealing pressure ring 7 is provided between the sealing and pressing flange 5 and the sealing packing 8. The cross section of the sealing pressure ring 7 is concave, and the end of the sealing pressure flange 5 adjacent to the sealing packing 8 extends into the concave notch of the sealing pressure ring 7. An annular groove is provided on the inner wall of the annular inner boss (10) adjacent to the sealing packing 8, and a sealing anti-pressure ring 9 is installed in the aforementioned annular groove.

[0031] In order to prevent the product from dislocating in the reverse direction during the engineering installation process and to prevent the sliding member 11 arranged between the inner and outer annular bosses from shifting, a limiting block 13 is arranged in the reducer 14 .

[0032] In this embodiment, the sliding member 11 is a sliding ring.

[0033] Example 2

[0034] like Figure 3 As shown, the basic structure of this embodiment is the same as that of embodiment 1, except that:

[0035] In order to maintain good sealing performance, 4-30 injection ports are evenly distributed along the same circumference at positions corresponding to the sealing filler 8 on the outer sleeve 6. The radial through hole built into each injection port is connected to the transverse hole on the waist. A screw plug with a hole is provided at the outer end of the radial through hole. The screw plug installed in the transverse hole crosses the radial through hole to form a sealing filler filling device 15 of the valve structure. During the use of the rotary compensator, if the sealing performance decreases and leakage occurs, the screw plug installed at the outer end of the injection port can be removed online, and then the screw plug in the transverse hole can be rotated to make the hole on the screw plug communicate with the radial through hole, and the sealing filler can be supplemented by a pressure gun facing the injection port. After the supplementation is completed, first tighten the screw plug in the transverse hole, then pull out the pressure gun, and then reinstall the screw plug at the outer end of the inlet. In this way, the sealing performance of the rotary compensator can be restored in time by supplementing the sealing filler online.

[0036] In this embodiment, an end face seal is provided in the cavity formed between the annular outer boss and the annular inner boss to replace the sliding member 11. The end face seal is made of a flexible material such as graphite, which can further ensure the sealing performance of the rotary compensator.

Claims

1. An end face sealing structure for a rotary compensator, comprising an annular inner boss (10) arranged on the inner surface of an outer sleeve (6), a sealing filler (8) arranged between a sealing clamping flange (5) and the annular inner boss (10), characterized in that A sealing pressure ring (7) is arranged between the sealing pressure flange (5) and the sealing packing (8), and the cross section of the sealing pressure ring (7) is concave-shaped, and the end of the sealing pressure flange (5) adjacent to the sealing packing (8) extends into the concave-shaped groove of the sealing pressure ring (7); an annular inner boss (10) is provided with an annular groove on one side adjacent to the sealing packing (8), and a sealing anti-pressure ring (9) is installed in the aforementioned annular groove.

2. A rotary compensator, comprising an inner tube (1), an outer tube (6), a reducer (14), and a sealing compression flange (5), wherein one end of the inner tube (1) extends into the outer tube (6), the sealing compression flange (5) is sleeved on the inner tube (1), and one end thereof extends into the outer tube (6), an annular inner boss (10) is provided on the inner surface of the outer tube (6), an annular outer boss (12) is provided on the outer surface of the inner tube (1), a sealing filler (8) is provided between the annular inner boss (10) and the end of the sealing compression flange (5) extending into the outer tube (6), a sliding member (11) or an end face seal is provided in the cavity formed between the annular outer boss (12) and the annular inner boss, characterized in that: A sealing pressure ring (7) is arranged between the sealing pressure flange and the sealing packing, and the cross section of the sealing pressure ring (7) is concave-shaped, and the end of the sealing pressure flange (5) adjacent to the sealing packing (8) extends into the concave-shaped groove of the sealing pressure ring (7); an annular groove is formed on the inner wall of the annular inner boss (10) adjacent to the sealing packing (8), and a sealing anti-pressure ring (9) is installed in the aforementioned annular groove.

3. The rotary compensator according to claim 2, characterized in that The outer sleeve (6) and the reducer (14) are an integrated structure formed in one piece.

4. The rotary compensator according to claim 2, characterized in that The outer sleeve (6) is provided with a sealing filler filling device (15).

5. The rotary compensator according to claim 2, characterized in that A limiting block is arranged inside the reducer (14).

6. The rotary compensator according to claim 2, characterized in that The sliding member (11) is a ball bearing or a sliding ring.

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