Reciprocating high-speed compressor packing seal structure and installation method

Abstract

The application discloses a reciprocating high-speed compressor packing seal structure and a mounting method. The seal structure comprises a throttling unit, a main seal unit and a preposition unit arranged in sequence along the direction from a cylinder to a crankshaft. The throttling unit comprises a low-pressure pressure-reducing ring and a high-pressure pressure-reducing ring arranged in sequence along the direction from the cylinder to the crankshaft. The main seal unit comprises a plurality of groups of seal boxes arranged along the direction from the cylinder to the crankshaft. Each group of seal boxes comprises a radial seal ring one, a tangential seal ring, a low-pressure flow resistance ring and a high-pressure flow resistance ring arranged in sequence along the direction from the cylinder to the crankshaft. The preposition unit comprises a radial seal ring two, a radial seal ring three, a support ring one, an axial spring, a support ring two, a radial seal ring four and a radial seal ring five arranged in sequence along the direction from the cylinder to the crankshaft. The packing seal structure has a long service life, and can ensure the safety of equipment and people when a seal part leaks.

Description

Technical Field

[0001] This invention relates to the field of compressors, and more specifically to a packing seal structure and installation method for a reciprocating high-speed compressor. Background Technology

[0002] The packing ring in a reciprocating compressor is a component that prevents high-pressure gas from leaking outwards along the piston rod. It is one of the most important parts of the compressor, and an improperly designed packing ring is one of the main external leakage pathways. Typically, the packing ring consists of a radial sealing ring, a tangential sealing ring, and a throttling ring, arranged sequentially from the high-pressure side to the low-pressure side.

[0003] Tangential sealing rings are the main components that prevent gas from leaking axially along the piston rod, such as... Figure 1 As shown, it consists of three arc-shaped plates. A bracelet-shaped small spring ring is installed in the circumferential groove of the outer ring, clamping the three arc-shaped plates together to grip the piston rod and create a seal. To ensure the arc-shaped plates can still grip the piston rod after the inner ring wears, a radial contraction gap of 1.5-2.5 mm needs to be left between the arc-shaped plates. It is precisely because of the existence of these three contraction gaps that gas is provided with pathways for radial and axial leakage, therefore a radial sealing ring is required.

[0004] The radial sealing ring, located on the high-pressure gas side, consists of three sector-shaped pieces and is secured by bracelet-shaped springs within the circumferential groove of the outer ring. This seals the three seams of the tangential sealing ring axially. A contraction gap is left between the three sector-shaped pieces to allow them to contract and grip the shaft after wear of the inner rings. To stagger the three contraction gaps of the tangential and radial sealing rings, locating pins are fixed to the arc-shaped pieces of the tangential sealing ring, and corresponding locating holes are machined into the sector-shaped pieces of the radial sealing ring.

[0005] The throttling ring primarily functions to throttle the gas flow. When leaking gas passes through the gap between the throttling ring and the piston rod, it reduces pressure, lightens the load on the sealing ring, and improves the overall efficiency of the packing seal ring system. Simultaneously, when the pressure inside the cylinder increases, the throttling ring will bear the pressure synchronized with the cylinder. Therefore, the quality of the throttling ring directly affects the service life of the entire packing seal system.

[0006] Because the inner ring of the packing seal ring is tightly fitted to the piston rod, friction occurs between them when the piston rod moves at high speed, generating a large amount of frictional heat and causing a localized temperature increase. This provides the conditions for corrosion of the packing seal ring. The packing seal ring closer to the compressor cylinder has the highest temperature, while the part farther away from the compressor cylinder has the lowest temperature. Inspection revealed that the inner ring of the packing seal ring is more severely corroded than the outer ring, with the degree of corrosion gradually decreasing from the inside out. Tangential seal ring damage mainly occurs in the following two ways:

[0007] 1) due to the too large gap between the pressure-reducing rings, the pressure entering the packing seal box is too high, the pressure difference between the two sides of the pressure-reducing ring is very small when compressed, the pressure entering the last-stage packing seal box is relatively high, the pressure in the cylinder is close to the inlet pressure, and the pressure in the packing seal box still maintains the pressure during compression, the pressure difference is as high as 2.3-6 MPa, the pressure in the packing seal box is reversed, and a huge burst effect is generated on the radial cut of the sealing ring, causing rupture.

[0008] 2) in the later stage of operation of the pressure-reducing ring, due to the wear of the inner diameter, the radial opening is closed, a gap is generated between the inner diameter and the piston rod, the pressure entering the packing seal box gradually increases, at the same time, the strength of the sealing ring is reduced due to wear, the burst effect caused by the reverse pressure relief gradually increases, and thus the last-stage sealing ring is broken along the stress concentration position. Once the last-stage sealing ring is broken, similar situations will occur on the next-stage sealing ring.

[0009] When the packing seal of the unit fails, the compressed medium will leak from the failure point and is not discharged from the system in time, so that the medium enters the crankcase to contaminate the lubricating oil, causing the lubricating oil to become black and deteriorate and be accompanied by medium outflow. More seriously, due to the long-term operation of the compressor in harsh conditions, the running parts such as the connecting rod big shoe, small shoe and main shaft shoe are abnormally worn, and thus the crankshaft and crosshead are worn, which not only damages the equipment but also pollutes the surrounding environment.

[0010] The applicant finds that the prior art at least has the following technical problems:

[0011] 1. The packing seal structure of the reciprocating compressor in the prior art is unreasonable, the piston rod moves at a high speed for a long time, which easily causes corrosion of the packing seal ring, when the packing seal of the unit fails, the compressed medium will leak from the failure point and is not discharged from the system in time, so that the medium enters the crankcase to contaminate the lubricating oil, causing the lubricating oil to become black and deteriorate and be accompanied by medium outflow.

[0012] 2. The packing seal structure of the reciprocating compressor in the prior art is unreasonable, when the packing seal fails, the lubricating oil is contaminated, and the compressor is operated in harsh conditions for a long time, which will cause abnormal wear of the running parts such as the connecting rod big shoe, small shoe and main shaft shoe, and thus the crankshaft and crosshead are worn, which not only damages the equipment but also pollutes the surrounding environment.

[0013] 3. The packing seal structure of the reciprocating compressor in the prior art is unreasonable, the service life is below 4000 h, the service life is short, the use cost is high, and the working efficiency is affected. SUMMARY

[0014] The application aims to provide a packing seal structure and installation method of a reciprocating high-speed compressor, so as to solve the technical problem that the packing seal structure of the reciprocating compressor in the prior art is unreasonable, the piston rod moves at high speed for a long time, the packing seal ring is easily corroded, when the packing seal of the unit fails, the compressed medium leaks from the failure point and is not discharged from the system in time, so that the medium enters the crankcase to contaminate the lubricating oil, and the lubricating oil is blackened and deteriorated with the medium leaking out.

[0015] To achieve the above-mentioned purpose, the application provides the following technical solutions.

[0016] The application provides a packing seal structure of a reciprocating high-speed compressor, which is provided with a throttling unit, a main sealing unit and a preposition unit in sequence along the direction from the cylinder to the crankshaft.

[0017] The throttling unit comprises a throttling box body and a low-pressure pressure-reducing ring and a high-pressure pressure-reducing ring arranged in sequence in the throttling box body along the direction from the cylinder to the crankshaft.

[0018] The main sealing unit comprises a plurality of sealing boxes arranged along the direction from the cylinder to the crankshaft; each sealing box comprises a sealing box body and a radial sealing ring, a tangential sealing ring I, a low-pressure flow resistance ring and a high-pressure flow resistance ring arranged in sequence in the sealing box body along the direction from the cylinder to the crankshaft.

[0019] The preposition unit comprises a mounting box body and a tangential sealing ring II, a tangential sealing ring III, a support ring I, an axial spring, a support ring II, a tangential sealing ring IV and a tangential sealing ring V arranged in sequence in the mounting box body along the direction from the cylinder to the crankshaft; and the tangential sealing ring II and the tangential sealing ring III and the tangential sealing ring IV and the tangential sealing ring V form bidirectional sealing structures, and the tangential sealing ring II and the tangential sealing ring III and the tangential sealing ring IV and the tangential sealing ring V are arranged in a staggered manner.

[0020] Optionally or preferably, when the tangential sealing ring II, the tangential sealing ring III, the tangential sealing ring IV and the tangential sealing ring V are all three-petal structures, the staggered angles between the tangential sealing ring II and the tangential sealing ring III and between the tangential sealing ring IV and the tangential sealing ring V are both 60°.

[0021] When the tangential sealing ring II, the tangential sealing ring III, the tangential sealing ring IV and the tangential sealing ring V are all four-petal structures, the staggered angles between the tangential sealing ring II and the tangential sealing ring III and between the tangential sealing ring IV and the tangential sealing ring V are both 45°.

[0022] Optionally or preferably, the low-pressure pressure-reducing ring is provided with a pressure relief groove near the surface of the cylinder, and the pressure relief groove is arranged along the radial direction of the low-pressure pressure-reducing ring.

[0023] Optionally or preferably, the low-pressure pressure relief ring and the high-pressure pressure relief ring are both made of PEEK material.

[0024] Optionally or preferably, the sealing box is provided with an installation ring groove for the radial sealing ring, the tangential sealing ring one, the low-pressure flow resistance ring and the high-pressure flow resistance ring. After the radial sealing ring and the tangential sealing ring one are installed in the sealing box, the outer wall of the radial sealing ring and the tangential sealing ring one and the inner wall of the installation ring groove of the sealing box have a gap of 0-50 μm.

[0025] Optionally or preferably, the low-pressure pressure relief ring and the high-pressure pressure relief ring are both made of PEEK material.

[0026] The application provides a mounting method of the above-mentioned reciprocating high-speed compressor packing seal structure, which comprises the following steps:

[0027] S1, grinding the sealing box of the main sealing unit

[0028] The outer surface of the sealing box of each group of sealing boxes of the main sealing unit is ground, so that the roughness of the sealing surface of each sealing box after grinding reaches the surface quality requirement of Ra0.80um, and the parallelism error of the two end surfaces of the sealing box of each group of sealing boxes is not more than 0.003mm.

[0029] S2, grinding the sealing ring in the main sealing unit and the pre-sealing unit

[0030] The inner hole of the radial sealing ring and the tangential sealing ring one in the main sealing unit are ground, and the inner hole of the tangential sealing ring two, the tangential sealing ring three, the tangential sealing ring four and the tangential sealing ring five in the pre-sealing unit are ground, so that the contact area of the radial sealing ring, the tangential sealing ring one, the tangential sealing ring two, the tangential sealing ring three, the tangential sealing ring four and the tangential sealing ring five with the piston rod is more than 70%.

[0031] S3, assembling the main sealing unit

[0032] The radial sealing ring, the tangential sealing ring one, the low-pressure resistance ring and the high-pressure resistance ring are sequentially installed into the sealing box body, and the axial static gaps of each sealing box body and the radial sealing ring, the tangential sealing ring one, the low-pressure resistance ring and the high-pressure resistance ring installed therein are controlled to be 0.30-0.45mm during assembly; meanwhile, the two planes of the radial sealing ring and the tangential sealing ring one are ground, and the parallelism errors of the two planes of the radial sealing ring and the two planes of the tangential sealing ring one are controlled to be not more than 0.003mm, and the surface roughness of the radial sealing ring and the tangential sealing ring one is controlled to be Ra1.60um-Ra3.20um, and no scratch is allowed; and during assembly, the radial sealing ring, the tangential sealing ring one, the low-pressure resistance ring and the high-pressure resistance ring are assembled in a way that the axial gaps gradually decrease by 0.01-0.02mm from the high-pressure side to the low-pressure side, and the assembly of one set of sealing boxes is completed; the above method is repeated to complete the assembly of multiple sets of sealing boxes.

[0033] S4, assembling the throttling unit and the preposition unit

[0034] The low-pressure pressure-reducing ring and the high-pressure pressure-reducing ring are installed into the throttling box body; the tangential sealing ring two, the tangential sealing ring three, the support ring one, the axial spring, the support ring two, the tangential sealing ring four and the tangential sealing ring five are installed into the mounting box body.

[0035] S5, assembling the packing seal structure by using the integral mounting method

[0036] The 0-shaped sealing ring between the sealing boxes in the main seal unit is replaced, the throttling unit, the main seal unit and the preposition unit are respectively installed on the compressor, and the piston rod is guided by using the guide head;

[0037] S6, the diameter of the gas pipe and the diameter of the gas exhaust pipe are increased, the nitrogen gas interface of the machine body is expanded to increase the nitrogen gas flow, and the leaked medium is discharged from the system in time; a nitrogen pressure reducing valve and a pressure gauge are additionally arranged on the nitrogen inlet pipeline to effectively control the nitrogen pressure and flow entering the packing chamber of the sealing structure.

[0038] Optionally or preferably, in the step S2, the inner holes of the radial sealing ring, the tangential sealing ring one, the tangential sealing ring two, the tangential sealing ring three, the tangential sealing ring four and the tangential sealing ring five are ground by using a process shaft coated with red lead powder.

[0039] Optionally or preferably, in the step S6, the diameter of the gas pipe, the diameter of the exhaust pipe and the nitrogen gas interface of the machine body are all increased by 0-15%.

[0040] Based on the above technical solutions, the embodiments of the present application can at least produce the following technical effects:

[0041] (1) The reciprocating high-speed compressor packing seal structure and installation method provided by the application, in order to reduce the impact load of high-pressure gas on the sealing ring and reduce the pressure difference borne by the sealing ring, a throttling unit is additionally arranged near the cylinder; the throttling unit comprises a low-pressure pressure relief ring and a high-pressure pressure relief ring, which are installed in the throttling box body close to the cylinder and mainly play the roles of throttling and pressure relief, so that the gas pressure borne by each subsequent sealing ring is reduced; the low-pressure pressure relief ring is provided with a pressure relief groove at the end surface close to the cylinder, thereby further improving the pressure relief effect.

[0042] (2) The reciprocating high-speed compressor packing seal structure and installation method provided by the application, in the main sealing unit, the sealing ring is subjected to the radial force from the sealing gas in addition to the action of the outer ring clamping spring, and the specific pressure of the sealing ring on the piston rod generated thereby is the main cause of the wear of the sealing ring, so reducing the sealing pressure and the outer diameter of the sealing ring can reduce the specific pressure, but the outer diameter is too small, which will reduce the strength of the sealing ring; considering these factors comprehensively, and through calculation of the thermal expansion gap of the sealing ring at 200 DEG C, in the design of the main sealing unit, the outer wall of each radial sealing ring and tangential sealing ring one and the inner wall of the installation ring groove of the sealing box body have a gap of 5-50 microns; the outer diameter of the radial sealing ring and the tangential sealing ring one is designed within the gap of 5-50 microns smaller than the inner diameter of the sealing box body installation ring groove, which guarantees the maximum outer diameter of the sealing ring (radial sealing ring, tangential sealing ring one), reduces the sealing pressure, and thus can consciously guide part of the gas to the surface of the piston rod in the process of compressor operation, reduces the specific pressure, and realizes that multiple sealing boxes jointly undertake the sealing task, which can effectively prevent the situation that only one group of packing sealing boxes undertakes the sealing task and the sealing ring of the group is worn out and fails earlier than other sealing rings; the application prolongs the service life of the overall sealing structure in the application by adding the throttling unit and guiding part of the gas to the surface of the piston rod and by multiple sealing boxes jointly undertaking the sealing task, thereby greatly prolonging the service life of the overall sealing structure in the application; the service life of the sealing structure in the application can reach more than 8000 hours, which is more than twice the service life of the sealing structure in the prior art.

[0043] (3) The reciprocating high-speed compressor packing seal structure and installation method provided by the application, the front part is borne by the bidirectional sealing ring group. When the sealing part leaks, the leaked gas can be exhausted or introduced into the compressor inlet for recycling. Since the sealing ring is subjected to the radial force from the nitrogen-filled gas in addition to the action of the axial spring, the pressure balance between the cylinder cavities of the compressor is maintained, the gas leakage is prevented, and the sealing effect is enhanced. The nitrogen inlet is connected with the gas leakage port to block the gas leakage and simultaneously carry away the leaked gas, the leaked gas is exhausted to the recycling system through the packing exhaust port, so as to ensure the safety of the equipment and the human body. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments or prior art description. Obviously, the drawings described below only illustrate some of the embodiments of the present application, and are not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0045] Figure 1 is a structural schematic diagram of embodiment 1 of the present application;

[0046] Figure 2 is a structural schematic diagram of a radial sealing ring in embodiment 1 of the present application;

[0047] Figure 3 is a structural schematic diagram of a tangential sealing ring in embodiment 1 of the present application;

[0048] Figure 4 is a structural schematic diagram of a low-pressure pressure-reducing ring in embodiment 1 of the present application;

[0049] Figure 5 is an installation direction schematic diagram of a throttling unit in embodiment 1 of the present application;

[0050] Figure 6 is an installation direction schematic diagram of a main sealing unit in embodiment 1 of the present application;

[0051] Figure 7 is an installation direction schematic diagram of a bidirectional sealing structure in a preposition unit in embodiment 1 of the present application;

[0052] Figure 8 is an assembly schematic diagram of a preposition unit in embodiment 1 of the present application.

[0053] In the figure: 1, throttling unit; 2, main sealing unit; 3, preposition unit; 4, throttling box body; 5, low-pressure pressure-reducing ring; 6, high-pressure pressure-reducing ring; 7, sealing box body; 8, radial sealing ring; 9, tangential sealing ring one; 10, low-pressure resistance ring; 11, high-pressure resistance ring; 12, installation box body; 13, tangential sealing ring two; 14, tangential sealing ring three; 15, support ring one; 16, axial spring; 17, support ring two; 18, tangential sealing ring four; 19, tangential sealing ring five; 20, pressure relief groove; 21, positioning hole. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of the present application more clear, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, and are not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0055] As Figures 1-8 shown:

[0056] Embodiment 1:

[0057] The application provides a reciprocating high-speed compressor packing seal structure, which is sequentially provided with a throttling unit 1, a main sealing unit 2 and a preposition unit 3 along the direction from a cylinder to a crankshaft.

[0058] The throttling unit 1 comprises a throttling box body 4 and a low-pressure pressure-reducing ring 5 and a high-pressure pressure-reducing ring 6 sequentially arranged in the throttling box body 4 along the direction from the cylinder to the crankshaft.

[0059] The main sealing unit 2 comprises a plurality of groups of sealing boxes 7 arranged along the direction from the cylinder to the crankshaft; each group of sealing boxes 7 comprises a sealing box body 7 and a radial sealing ring 8, a tangential sealing ring one 9, a low-pressure flow-resisting ring 10 and a high-pressure flow-resisting ring 11 sequentially arranged in the sealing box body 7 along the direction from the cylinder to the crankshaft.

[0060] The preposition unit 3 comprises a mounting box body 12 and a tangential sealing ring two 13, a tangential sealing ring three 14, a support ring one 15, an axial spring 16, a support ring two 17, a tangential sealing ring four 18 and a tangential sealing ring five 19 sequentially arranged in the mounting box body 12 along the direction from the cylinder to the crankshaft; and the tangential sealing ring two 13 and the tangential sealing ring three 14 and the tangential sealing ring four 18 and the tangential sealing ring five 19 form bidirectional sealing structures, and the tangential sealing ring two 13 and the tangential sealing ring three 14 and the tangential sealing ring four 18 and the tangential sealing ring five 19 are installed in a staggered mode.

[0061] The application provides a reciprocating high-speed compressor packing seal structure and a mounting method, in order to reduce the impact load of high-pressure gas on the sealing ring and reduce the pressure difference borne by the sealing ring, a throttling unit 1 is additionally arranged close to the cylinder; the throttling unit 1 comprises a low-pressure pressure-reducing ring 5 and a high-pressure pressure-reducing ring 6, which are mounted in a throttling box body 4 close to the cylinder and play a main throttling and pressure-reducing role, so that the gas pressure borne by the sealing rings in the following sealing units is reduced; the low-pressure pressure-reducing ring 5 is provided with a pressure-reducing groove 20 at the end surface close to the cylinder, so that the pressure-reducing effect is further improved.

[0062] The application provides a packing seal structure and installation method of a reciprocating high-speed compressor, wherein the main seal unit 2 is subjected to the radial force of the sealing gas in addition to the clamping spring of the outer ring, and the specific pressure of the sealing ring to the piston rod is the main cause of the wear of the sealing ring, so that the specific pressure is reduced by reducing the outer diameter of the sealing ring, but the strength of the sealing ring is reduced if the outer diameter is too small, and the factors are considered comprehensively, and the outer wall of the radial sealing ring 8 and the tangential sealing ring 1 9 in each sealing box 7 is provided with a gap of 5-50 mu m with the inner wall of the installation ring groove of the sealing box body 7 when the main seal unit 2 is designed; the outer diameter of the radial sealing ring 8 and the tangential sealing ring 1 9 is designed in the gap of 5-50 mu m smaller than the inner diameter of the sealing box body 7 installation ring groove, the maximum outer diameter of the sealing ring (the radial sealing ring 8 and the tangential sealing ring 1 9) is guaranteed, the sealing pressure is reduced, and a part of the gas can be consciously guided to the surface of the piston rod in the process of the operation of the compressor, the specific pressure is reduced, a plurality of sealing boxes 7 can jointly undertake the sealing task, the situation that the sealing ring of a group of packing sealing boxes 7 is worn and fails first can be prevented, the throttling unit 1 is additionally arranged, a part of the gas is guided to the surface of the piston rod, the sealing task is jointly undertaken by the plurality of sealing boxes 7, and the service life of the whole sealing structure in the application is greatly prolonged; the service life of the sealing structure in the application can reach more than 8000 h, and can be more than twice the service life of the sealing structure in the prior art.

[0063] The application provides a packing seal structure and installation method of a reciprocating high-speed compressor, wherein the main seal unit 2 is subjected to the radial force of the sealing gas in addition to the clamping spring of the outer ring, and the specific pressure of the sealing ring to the piston rod is the main cause of the wear of the sealing ring, so that the specific pressure is reduced by reducing the outer diameter of the sealing ring, but the strength of the sealing ring is reduced if the outer diameter is too small, and the factors are considered comprehensively, and the outer wall of the radial sealing ring 8 and the tangential sealing ring 1 9 in each sealing box 7 is provided with a gap of 5-50 mu m with the inner wall of the installation ring groove of the sealing box body 7 when the main seal unit 2 is designed; the outer diameter of the radial sealing ring 8 and the tangential sealing ring 1 9 is designed in the gap of 5-50 mu m smaller than the inner diameter of the sealing box body 7 installation ring groove, the maximum outer diameter of the sealing ring (the radial sealing ring 8 and the tangential sealing ring 1 9) is guaranteed, the sealing pressure is reduced, and a part of the gas can be consciously guided to the surface of the piston rod in the process of the operation of the compressor, the specific pressure is reduced, a plurality of sealing boxes 7 can jointly undertake the sealing task, the situation that the sealing ring of a group of packing sealing boxes 7 is worn and fails first can be prevented, the throttling unit 1 is additionally arranged, a part of the gas is guided to the surface of the piston rod, the sealing task is jointly undertaken by the plurality of sealing boxes 7, and the service life of the whole sealing structure in the application is greatly prolonged; the service life of the sealing structure in the application can reach more than 8000 h, and can be more than twice the service life of the sealing structure in the prior art.

[0064] As an optional embodiment, when the tangential sealing ring two 13, the tangential sealing ring three 14, the tangential sealing ring four 18 and the tangential sealing ring five 19 are all three-petal structures, the dislocation angles between the tangential sealing ring two 13 and the tangential sealing ring three 14 and between the tangential sealing ring four 18 and the tangential sealing ring five 19 are all 60°.

[0065] When the tangential sealing ring two 13, the tangential sealing ring three 14, the tangential sealing ring four 18 and the tangential sealing ring five 19 are all four-petal structures, the dislocation angle between the tangential sealing ring two 13 and the tangential sealing ring three 14 and the dislocation angle between the tangential sealing ring four 18 and the tangential sealing ring five 19 are both 45°.

[0066] As an optional embodiment, the positioning structure is provided between the tangential sealing ring two 13 and the tangential sealing ring three 14 and between the tangential sealing ring four 18 and the tangential sealing ring five 19, which is a positioning hole 21 arranged on the tangential sealing ring two 13 and a positioning pin arranged on the tangential sealing ring three 14 and matched with the positioning hole 21 on the tangential sealing ring two 13, and a positioning hole 21 arranged on the tangential sealing ring four 18 and a positioning pin arranged on the tangential sealing ring five 19 and matched with the positioning hole 21 on the tangential sealing ring four 18. The positioning structure is arranged to facilitate the dislocation installation between the tangential sealing ring two 13 and the tangential sealing ring three 14 and between the tangential sealing ring four 18 and the tangential sealing ring five 19. The structure of the positioning pin is not shown in the drawing, and the structure of the positioning pin in the prior art can be used and matched with the positioning hole 21, which can play a positioning role.

[0067] As an optional embodiment, the low-pressure relief ring 5 is provided with a pressure relief groove 20 close to the cylinder side surface, and the pressure relief groove 20 is arranged along the radial direction of the low-pressure relief ring 5.

[0068] As an optional embodiment, the labyrinth seal is used between the low-pressure relief ring 5 and the piston rod and between the high-pressure relief ring 6 and the piston rod.

[0069] As an optional embodiment, the installation ring groove of the radial sealing ring 8, the tangential sealing ring one 9, the low-pressure flow resistance ring 10 and the high-pressure flow resistance ring 11 is arranged in the sealing box body 7. After the radial sealing ring 8 and the tangential sealing ring one 9 are installed in the sealing box body 7, the outer wall of the radial sealing ring 8 and the tangential sealing ring one 9 and the inner wall of the installation ring groove of the sealing box body 7 have a gap of 5-50 μm.

[0070] As an optional embodiment, the low-pressure relief ring 5 and the high-pressure relief ring 6 are both made of PEEK material.

[0071] Embodiment 2:

[0072] The installation method of the packing seal structure of the reciprocating high-speed compressor in embodiment 1 provided by the application comprises the following steps:

[0073] S1, grinding the sealing box body 7 of the main sealing unit 2

[0074] The outer surface of the seal box body 7 of each group of seal boxes 7 of the main sealing unit 2 is ground, so that the roughness of the sealing surface of each seal box body 7 after grinding reaches the surface quality requirement of Ra0.80um, and the parallelism error of the two end faces of each seal box body 7 of each group of seal boxes 7 is not more than 0.003mm;

[0075] S2, grinding the seal rings in the main sealing unit 2 and the pre-sealing unit 3

[0076] The inner holes of the radial seal ring 8 and the tangential seal ring one 9 in the main sealing unit 2 are ground by using a process shaft coated with red lead powder, and the inner holes of the tangential seal ring two 13, the tangential seal ring three 14, the tangential seal ring four 18 and the tangential seal ring five 19 in the pre-sealing unit 3 are ground by using a process shaft coated with red lead powder, so that the contact area of the radial seal ring 8, the tangential seal ring one 9, the tangential seal ring two 13, the tangential seal ring three 14, the tangential seal ring four 18 and the tangential seal ring five 19 with the piston rod is more than 70%;

[0077] S3, assembling the main sealing unit 2

[0078] The radial seal ring 8, the tangential seal ring one 9, the low-pressure choke ring 10 and the high-pressure choke ring 11 are sequentially assembled into the seal box body 7, and the axial static clearance of each seal box body 7 and the radial seal ring 8, the tangential seal ring one 9, the low-pressure choke ring 10 and the high-pressure choke ring 11 assembled therein is controlled to be 0.30-0.45mm during the assembly process; at the same time, the two planes of the radial seal ring 8 and the tangential seal ring one 9 are ground, and the parallelism error of the two planes of the radial seal ring 8 and the tangential seal ring one 9 is controlled to be not more than 0.003mm, and the surface roughness of the radial seal ring 8 and the tangential seal ring one 9 is controlled to be Ra1.60um-Ra3.20um, and no scratches are allowed; and during the assembly process, the radial seal ring 8, the tangential seal ring one 9, the low-pressure choke ring 10 and the high-pressure choke ring 11 are assembled by gradually reducing the axial clearance from the high-pressure side to the low-pressure side by 0.01-0.02mm, and the assembly of one group of seal boxes 7 is completed; the above method is repeated to complete the assembly of multiple groups of seal boxes 7;

[0079] S4, assembling the throttling unit 1 and the pre-sealing unit 3

[0080] The low-pressure pressure-reducing ring 5 and the high-pressure pressure-reducing ring 6 are assembled into the throttling box body 4; the tangential seal ring two 13, the tangential seal ring three 14, the support ring one 15, the axial spring 16, the support ring two 17, the tangential seal ring four 18 and the tangential seal ring five 19 are assembled into the mounting box body 12;

[0081] S5, assembling the packing seal structure by using the whole mounting method

[0082] Replace the O-shaped sealing ring between the sealing box 7 in the main sealing unit 2, install the throttle unit 1, the main sealing unit 2 and the preposition unit 3 on the compressor respectively, and guide the piston rod by using the guide head;

[0083] S6, increase the diameter of the air pipe and the diameter of the exhaust pipe, and enlarge the nitrogen gas interface of the machine body to increase the nitrogen flow and timely discharge the leaked medium from the system; a nitrogen pressure reducing valve and a pressure gauge are additionally arranged on the nitrogen inlet pipeline to effectively control the nitrogen pressure and flow entering the packing chamber of the sealing structure; specifically, the diameter of the air pipe, the diameter of the exhaust pipe and the nitrogen gas interface of the machine body are all increased by 0-15%.

[0084] The sealing principle of the packing sealing structure in the application is:

[0085] ①First, the throttle unit 1 is additionally arranged near the cylinder side, the throttle unit 1 includes a low-pressure reducing ring 5 and a high-pressure reducing ring 6, and is installed in the throttle box body 4 close to the cylinder; the setting of the throttle unit 1 reduces the impact load of high-pressure gas on the subsequent sealing ring, and reduces the gas pressure borne by the sealing ring in the main sealing unit 2 and the preposition unit 3; the throttle unit 1 mainly plays a throttling and pressure reducing role,

[0086] ②Further, in the design of the sealing structure, the application calculates the thermal expansion gap of the sealing ring at 200 DEG C, and in the design of the main sealing unit 2, the outer wall of the radial sealing ring 8 and the tangential sealing ring one 9 has a gap of 5-50 mu m with the inner wall of the installation ring groove of the sealing box body 7; the outer diameter of the radial sealing ring 8 and the tangential sealing ring one 9 is designed in the gap of 5-50 mu m smaller than the inner diameter of the sealing box body 7 installation ring groove, which guarantees the maximum outer diameter of the sealing ring (radial sealing ring 8 and tangential sealing ring one 9), reduces the sealing pressure, so that part of the gas can be consciously guided to the surface of the piston rod in the process of the operation of the compressor, which can effectively prevent the situation that the sealing ring is worn out and fails first because only one group of packing sealing boxes 7 bear the sealing task; the sealing structure designed in the application is jointly borne by three groups of sealing rings, thereby prolonging the service life of the whole sealing structure.

[0087] When the sealed working cylinder end gas is compressed, the sealing principle of the main sealing unit 2 is that the packing seal ring (radial seal ring 8, tangential seal ring 1 9) is pressed to the low pressure side by the high pressure gas in the cylinder, and the gas enters the outside of the packing seal ring (radial seal ring 8, tangential seal ring 1 9) from the axial gap between the packing seal ring (radial seal ring 8, tangential seal ring 1 9) and the ring groove 7 and the notch gap of the radial seal ring 8, and three sealing surfaces are formed under the action of the gas pressure, which are respectively: the sealing surface formed by the notch of the radial seal ring 8 and the tangential seal ring 1 9, the sealing surface formed by the tangential seal ring 1 9 and the surface of the piston rod, and the sealing surface formed by the tangential seal ring 1 9 and the inner side of the ring groove; thus, the gas leakage is prevented, thereby achieving the sealing effect.

[0088] When the cylinder is inhaling, the gas flows back into the cylinder through the notch gap of the radial seal ring 8, and the gas pressure in the packing ring groove gradually decreases, so that in the next compression process, the front and back of the packing seal ring (radial seal ring 8, tangential seal ring 1 9) can establish a new pressure difference, so that the packing seal ring (radial seal ring 8, tangential seal ring 1 9) can form three sealing surfaces again, thereby achieving the sealing effect.

[0089] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A packing seal structure for a reciprocating high-speed compressor, characterized by ,along the direction of cylinder to crankshaft in turn provided with throttle unit (1), main sealing unit (2), front unit (3);Wherein, the throttle unit (1) includes throttle box (4) and low pressure relief ring (5), high pressure relief ring (6) are sequentially arranged in throttle box (4) along the direction of cylinder to crankshaft; The main sealing unit (2) includes a plurality of sealing boxes (7) arranged along the direction of cylinder to crankshaft;Each group of sealing box (7) includes sealing box (7) and radial sealing ring (8), tangential sealing ring one (9), low pressure resistance ring (10), high pressure resistance ring (11) are sequentially arranged in sealing box (7) along the direction of cylinder to crankshaft; The front unit (3) includes mounting box (12) and tangential sealing ring two (13), tangential sealing ring three (14), support ring one (15), axial spring (16), support ring two (17), tangential sealing ring four (18), tangential sealing ring five (19) are sequentially arranged in mounting box (12) along the direction of cylinder to crankshaft;And tangential sealing ring two (13) and tangential sealing ring three (14) and tangential sealing ring four (18) and tangential sealing ring five (19) form bidirectional sealing structure, tangential sealing ring two (13) and tangential sealing ring three (14) and tangential sealing ring four (18) and tangential sealing ring five (19) are all installed in staggered manner; The sealing box (7) is provided with the installation ring groove of radial sealing ring (8), tangential sealing ring one (9), low pressure resistance ring (10), high pressure resistance ring (11) in it: after installing radial sealing ring (8), tangential sealing ring one (9) into sealing box (7), the outer wall of radial sealing ring (8) and tangential sealing ring one (9) and the inner wall of the installation ring groove of sealing box (7) have 5-50um gap.

2. The packing seal structure of a reciprocating high-speed compressor according to claim 1, characterized in that When tangential sealing ring two (13), tangential sealing ring three (14), tangential sealing ring four (18), tangential sealing ring five (19) are all three petal structure, the staggered angle between tangential sealing ring two (13) and tangential sealing ring three (14) and tangential sealing ring four (18) and tangential sealing ring five (19) is 60°: When tangential sealing ring two (13), tangential sealing ring three (14), tangential sealing ring four (18), tangential sealing ring five (19) are all four petal structure, the staggered angle between tangential sealing ring two (13) and tangential sealing ring three (14) and tangential sealing ring four (18) and tangential sealing ring five (19) is 45°.

3. The packing seal structure of a reciprocating high-speed compressor according to claim 1, characterized in that The low pressure relief ring (5) is provided with pressure relief groove (20) on the surface close to the cylinder side The low pressure relief ring (5) and the piston rod, the high pressure relief ring (6) and the piston rod are all adopted labyrinth seal.

4. The packing seal structure of a reciprocating high-speed compressor according to claim 1, characterized in that The low pressure relief ring (5), high pressure relief ring (6) are all prepared by PEEK material.

5. The packing seal structure of a reciprocating high-speed compressor according to claim 1, characterized in that It includes the following steps:

6. A method of installing a packing seal for a high-speed reciprocating compressor as claimed in any one of claims 1 to 5, characterized in that S1, grinding the sealing box (7) of main sealing unit (2) ​ Grinding the outer surface of the seal box body (7) of each group of seal boxes (7) of the main sealing unit (2) to make the roughness of the sealing surface of each seal box body (7) after grinding reach the surface quality requirement of Ra0.80um, and ensure that the parallelism error of the two end faces of each group of seal box bodies (7) is not more than 0.003mm; S2, grinding the seal ring in the main sealing unit (2) and the front unit (3) Grinding the inner hole of the radial seal ring (8) and the tangential seal ring one (9) in the main sealing unit (2), and grinding the inner hole of the tangential seal ring two (13), the tangential seal ring three (14), the tangential seal ring four (18) and the tangential seal ring five (19) in the front unit (3), so that the contact area of the radial seal ring (8), the tangential seal ring one (9), the tangential seal ring two (13), the tangential seal ring three (14), the tangential seal ring four (18) and the tangential seal ring five (19) with the piston rod is more than 70%; S3, assembling the main sealing unit (2) The radial seal ring (8), the tangential seal ring one (9), the low pressure resistance ring (10) and the high pressure resistance ring (11) are sequentially assembled into the seal box body (7), and the axial static clearance of each seal box body (7) and the radial seal ring (8), the tangential seal ring one (9), the low pressure resistance ring (10) and the high pressure resistance ring (11) assembled therein is controlled to be 0.30-0.45mm; At the same time, the two planes of the radial seal ring (8) and the tangential seal ring one (9) are ground, and the parallelism error of the two planes of the radial seal ring (8) and the tangential seal ring one (9) is controlled to be not more than 0.003mm, and the surface roughness of the radial seal ring (8) and the tangential seal ring one (9) is controlled to be Ra1.60um-Ra3.20um, and there is no scratch; And in the process of assembling, the radial seal ring (8), the tangential seal ring one (9), the low pressure resistance ring (10) and the high pressure resistance ring (11) are assembled from high pressure side to low pressure side, the axial clearance is gradually reduced by 0.01-0.02mm, and the assembly of one group of seal boxes (7) is completed; Repeat the above method to complete the assembly of multiple groups of seal boxes (7); S4, assembling the throttling unit (1) and the front unit (3) The low pressure pressure reducing ring (5) and the high pressure pressure reducing ring (6) are assembled into the throttling box body (4); The tangential seal ring two (13), the tangential seal ring three (14), the support ring one (15), the axial spring (16), the support ring two (17), the tangential seal ring four (18) and the tangential seal ring five (19) are assembled into the mounting box body (12); S5, assembling the packing seal structure by integral mounting method Replace the O-shaped sealing ring between the sealing box (7) in the main sealing unit (2), install the throttle unit (1), the main sealing unit (2) and the pre-sealing unit (3) on the compressor respectively, and guide the piston rod with the guide head; S6, increase the diameter of the air pipe and the diameter of the exhaust pipe, and enlarge the nitrogen gas interface of the machine body to increase the nitrogen flow and discharge the leaked medium from the system in time; Add an ammonia pressure reducing valve and a pressure gauge on the nitrogen inlet pipeline to effectively control the nitrogen pressure and flow entering the sealing structure stuffing box.

7. The method of installing a packing seal for a reciprocating high- speed compressor of claim 6, wherein In the step S2, the inner holes of the radial sealing ring (8), the tangential sealing ring one (9), the tangential sealing ring two (13), the tangential sealing ring three (14), the tangential sealing ring four (18) and the tangential sealing ring five (19) are ground by a process shaft coated with red lead powder.

8. The method of installing a packing seal for a reciprocating high- speed compressor of claim 7, wherein In the step S6, the diameter of the air pipe, the diameter of the exhaust pipe and the nitrogen gas interface of the machine body are all increased by 0-15%.

Images