Cartridge mechanical seals

Abstract

The present invention discloses a container-type mechanical seal, comprising: a shaft sleeve, a sealing box is arranged outside the shaft sleeve, a connecting seat and a gland are arranged outside the medium end of the sealing box and the atmosphere end of the sealing box respectively, the gland is fixed to the atmosphere end of the sealing box, a dynamic ring assembly including a dynamic ring and a static ring assembly including a static ring are arranged between the sealing box and the shaft sleeve, the dynamic ring assembly is connected to the shaft sleeve and rotates synchronously with the shaft sleeve, the static ring assembly is installed on the inner wall of the sealing box, a compensation mechanism is also arranged between the static ring assembly and the sealing box, under the action of the compensation mechanism, the dynamic ring and the static ring are always in contact and sealed, a spherical joint connection structure is adopted between the medium end of the sealing box and the connecting seat, the spherical joint connection structure makes the medium end of the sealing box and the connecting seat not separate, and the connecting seat can be universally rotated, and a limiting mechanism is also arranged between the medium end of the sealing box and the connecting seat. The advantages of the present invention are: it is not only suitable for sealing under ordinary working conditions, but also suitable for sealing under high and ultra-high temperatures.

Description

Technical Field

[0001] The invention relates to the technical field of shaft mechanical sealing devices, and in particular to a containerized mechanical sealing component. Background Art

[0002] Mechanical seals are usually used as seals between rotating shafts and equipment. They are devices that consist of at least one pair of end faces that are almost perpendicular to the axis of the rotating shaft, which maintain contact and slide relative to each other under the action of fluid pressure, elastic force or magnetic force of the compensation mechanism, and cooperation with auxiliary seals to achieve leakage prevention.

[0003] The structure of a traditional container-type mechanical seal usually includes: a shaft sleeve, a sealing box is arranged outside the shaft sleeve, and the two ends of the sealing box are respectively a sealing box medium end and a sealing box atmosphere end. As the name implies, the sealing box medium end is the end of the sealing box close to the medium in the equipment cylinder, and the sealing box atmosphere end is the end of the sealing box away from the equipment cylinder and located in the atmosphere. The outer sides of the sealing box medium end and the sealing box atmosphere end are respectively fixedly connected with a connecting seat and a pressure cover, and a dynamic ring assembly including a dynamic ring and a static ring assembly including a static ring are arranged between the sealing box and the shaft sleeve. The dynamic ring assembly is connected to the shaft sleeve and rotates synchronously with the shaft sleeve, and a sealing mechanism is arranged between the dynamic ring assembly and the outer wall of the shaft sleeve. The static ring assembly is installed on the inner wall of the sealing box, and a sealing mechanism is arranged between the static ring assembly and the inner wall of the sealing box. A compensation mechanism is also arranged between the static ring assembly and the sealing box, and under the action of the compensation mechanism, the dynamic ring and the static ring are always in contact and sealed.

[0004] During long-term use, it is found that the traditional structure of the containerized mechanical seal can usually only be used for sealing in relatively low temperature conditions and occasions where the leakage requirement is not high. Once the temperature inside the equipment cylinder is high, the equipment cylinder will undergo a large deformation under high temperature conditions. The deformation of the equipment cylinder will inevitably cause the connection seat and the sealing box to deviate and deform, thereby changing the relative position of the dynamic ring and the static ring, resulting in the failure of the seal between the dynamic ring and the static ring. This makes the traditional structure of the containerized mechanical seal unable to meet the sealing requirements under high temperature conditions. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a container-type mechanical seal, whose static ring and dynamic ring can maintain a stable and reliable sealing state at high temperatures, so that the mechanical seal can be suitable for sealing under high temperature conditions and can maintain an excellent sealing effect under high temperature working conditions.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is: a container-type mechanical seal, comprising: a shaft sleeve, a sealing box is arranged outside the shaft sleeve, the two ends of the sealing box are respectively a medium end of the sealing box and an atmospheric end of the sealing box, a connecting seat and a gland are arranged on the outer sides of the medium end of the sealing box and the atmospheric end of the sealing box, the gland is fixed to the atmospheric end of the sealing box, a dynamic ring assembly including a dynamic ring and a static ring assembly including a static ring are arranged between the sealing box and the shaft sleeve, the dynamic ring assembly is connected to the shaft sleeve and rotates synchronously with the shaft sleeve, a first sealing mechanism is arranged between the dynamic ring assembly and the outer wall of the shaft sleeve, and the static ring assembly is installed On the inner wall of the sealing box, a second sealing mechanism is arranged between the static ring assembly and the inner wall of the sealing box, and a compensation mechanism is also arranged between the static ring assembly and the sealing box. Under the action of the compensation mechanism, the dynamic ring and the static ring are always in contact and sealed. The sealing support of the medium end of the sealing box is on the connecting seat, and a spherical joint connection structure is adopted between the medium end of the sealing box and the connecting seat. The spherical joint connection structure makes the medium end of the sealing box and the connecting seat inseparable, and the connecting seat can make a universal rotation relative to the medium end of the sealing box. A limiting mechanism for limiting the rotation of the sealing box following the shaft sleeve is also arranged between the medium end of the sealing box and the connecting seat.

[0007] Furthermore, in the aforementioned container-type mechanical seal, the spherical joint connection structure between the sealing box medium end and the connecting seat includes: the outer side wall of the sealing box medium end is a spherical surface, a connecting groove is provided on the connecting seat located on one side of the sealing box medium end, the inner side wall of the connecting groove is a spherical surface that matches the outer side wall of the sealing box medium end, the spherical surface of the sealing box medium end is wrapped and blocked by the connecting groove, and a rotation gap is left between the bottom of the connecting groove and the end of the sealing box medium end for the connecting seat to make a universal rotation relative to the sealing box medium end.

[0008] Furthermore, in the aforementioned container-type mechanical seal, the structure of the limiting mechanism includes: at least one limiting groove is opened on the inner wall of the connecting groove, and a limiting pin is arranged in each limiting groove, and the limiting pin is arranged on the medium end of the sealing box, and a gap is left between the limiting pin and the limiting groove for the connecting seat to make a universal rotation relative to the medium end of the sealing box.

[0009] Furthermore, in the aforementioned container-type mechanical seal, the connecting groove comprises a first connecting groove and a second connecting groove which are connected to each other, the inner side walls of the first connecting groove and the second connecting groove are spherical surfaces which match the outer wall of the medium end of the sealing box respectively, the first connecting groove is opened on the connecting seat, the second connecting groove is arranged on the inner wall of the locking ring, the locking ring is fixed on the connecting seat outside the first connecting groove, the medium end of the sealing box can be directly extended into the first connecting groove, and the locking ring blocks the medium end of the sealing box in the first connecting groove and the second connecting groove; the limiting groove is opened on the inner wall of the locking ring.

[0010] Furthermore, in the aforementioned container-type mechanical seal, the dynamic ring assembly also includes a dynamic ring seat, the dynamic ring seat is fixedly mounted on the shaft sleeve, the dynamic ring is installed on the dynamic ring seat, and the dynamic ring and the dynamic ring seat are sealed; the first sealing mechanism includes a first sealing ring, and the first sealing ring is arranged between the dynamic ring seat and the outer wall of the shaft sleeve.

[0011] Furthermore, in the aforementioned container-type mechanical seal, the stationary ring assembly also includes a push ring, the compensation mechanism includes a compression spring, the two ends of the compression spring are respectively pressed on the push ring and the spring seat, the stationary ring is installed on the push ring, the push ring is clamped in the guide groove on the inner wall of the sealing box, and under the guidance of the guide groove, the push ring can only move axially along the sealing box, the spring seat is fixed on the inner wall of the sealing box, and under the action of the compression spring, the stationary ring is always in contact and sealed with the dynamic ring; the second sealing mechanism includes a second sealing ring, and the second sealing ring is sealed between the outer wall of the stationary ring and the inner wall of the sealing box.

[0012] Furthermore, in the aforementioned container-type mechanical seal, a sealing packing is arranged between the shaft sleeve and the connecting seat, and the two ends of the sealing packing are respectively clamped between the retaining ring and the packing bushing, the retaining ring is arranged on the connecting seat, the packing bushing is arranged on the packing seat, the packing seat is sleeved outside the shaft sleeve and the seal is clamped on the inner wall of the sealing box; a lip seal ring is arranged between the packing seat and the shaft sleeve, and the lip seal ring is clamped between the packing seat and the packing bushing.

[0013] Furthermore, in the aforementioned container-type mechanical seal, a thermal insulation gap is arranged between the dynamic ring seat and the packing seat, installation gaps are reserved between the dynamic ring seat and the inner wall of the sealing box, and between the sealing positions of the dynamic ring and the static ring and the inner wall of the sealing box, the thermal insulation gap and the installation gap are connected to form a thermal insulation sealing chamber; an air inlet connected to a high-pressure gas source is arranged on the sealing box, and the air inlet is connected to the thermal insulation sealing chamber.

[0014] Furthermore, in the aforementioned container-type mechanical seal, a sliding bearing is arranged between the atmospheric end of the sealing box and the shaft sleeve, the inner ring of the sliding bearing is fixed to the outer wall of the shaft sleeve, the outer ring of the sliding bearing is fixed to the inner wall of the sealing box, and a sliding gap is left between the pressure cover and the inner ring of the sliding bearing for axial displacement of the shaft sleeve relative to the sealing box.

[0015] Furthermore, in the aforementioned container-type mechanical seal, a fixing mechanism for fixing the sleeve to the rotating shaft is provided at the end of the sleeve outside the gland, and the structure of the fixing mechanism includes: a fastening ring with a notch, the notch makes the fastening ring not closed in the circumference, the fastening ring includes a fastening ring body, a fastening cone is connected to the fastening ring body, the outer wall diameter of the fastening cone gradually decreases from away from the sleeve to close to the sleeve, a connecting ring is provided at the end of the sleeve, and a conical pipe section with a diameter gradually decreasing from the outside to the inside is provided at the end of the sleeve; the fastening cone extends into the conical pipe section, and the fastening ring body and the connecting ring are tightened and fixed by fastening bolts.

[0016] Furthermore, in the aforementioned container-type mechanical seal, a cooling chamber is provided in the body of the sealing box, a cooling medium inlet and a cooling medium outlet are provided on the cooling chamber, and the cooling chamber is located outside the sealing position of the dynamic ring and the static ring.

[0017] Furthermore, in the aforementioned container-type mechanical seal, a plurality of sealing grooves are arranged at intervals in the axial direction on the inner wall of the sleeve, and a third sealing ring is arranged in each sealing groove.

[0018] The advantages of the present invention are: it can not only better meet the sealing requirements under ordinary working conditions, but also be suitable for sealing under conditions where the temperature in the equipment cylinder reaches high temperature or even ultra-high temperature, such as sealing under conditions where the temperature of the equipment cylinder reaches 650°C. When the seal described in the present invention is used under such ultra-high temperature conditions, the dynamic ring and the static ring always maintain a stable and reliable sealing state. Therefore, the seal described in the present invention has a wider range of applications, the sealing effect is effectively improved, and the service life of the seal is greatly extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of the container-type mechanical seal described in the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0021] like Figure 1As shown, the container-type mechanical seal comprises: a sleeve 1, a sealing box 2 is arranged outside the sleeve 1, and the two ends of the sealing box 2 are respectively a sealing box medium end 21 and a sealing box atmosphere end 22. A connecting seat 3 and a gland 4 are arranged on the outside of the sealing box medium end 21 and the outside of the sealing box atmosphere end 22. The sleeve 1 is used to be installed outside the rotating shaft 100, and the sleeve 1 rotates synchronously with the rotating shaft 100. In this embodiment, a plurality of sealing grooves are arranged at intervals in the axial direction of the inner wall of the sleeve 1, and a third sealing ring 15 is arranged in each sealing groove. The third sealing ring 15 is used for sealing between the sleeve 1 and the rotating shaft 100, and the sealing grooves are usually arranged at the positions of the two ends of the inner wall of the sleeve 1. The connecting seat 3 is used for fixed connection with the equipment cylinder, and the connecting seat 3 can usually adopt a flange. The connecting seat 3 and the gland 4 are both sleeved outside the sleeve 1, and the gland 4 is fixed to the sealing box atmosphere end 22, and the gland 4 and the sleeve 1 are sealed by a sealing ring.

[0022] A dynamic ring assembly including a dynamic ring 5 and a static ring assembly including a static ring 6 are arranged between the sealing box 2 and the sleeve 1. The dynamic ring assembly is connected to the sleeve 1 and rotates synchronously with the sleeve 1. A first sealing mechanism is arranged between the dynamic ring assembly and the outer wall of the sleeve 1. The static ring assembly is mounted on the inner wall of the sealing box 2, and a second sealing mechanism is arranged between the static ring assembly and the inner wall of the sealing box 1. A compensation mechanism is also arranged between the static ring assembly and the sealing box 2, and under the action of the compensation mechanism, the dynamic ring 5 and the static ring 6 are always in contact and sealed.

[0023] In this embodiment, the dynamic ring assembly further includes a dynamic ring seat 51, which is fixedly sleeved on the shaft sleeve 1, and the dynamic ring 5 is installed on the dynamic ring seat 51, and a sealing ring is provided between the outer wall of the dynamic ring 5 and the dynamic ring seat 51. The first sealing mechanism includes a first sealing ring 52, and the first sealing ring 52 is sealed between the dynamic ring seat 51 and the outer wall of the shaft sleeve 1.

[0024] In this embodiment, the stationary ring assembly also includes a push ring 62, and the compensation mechanism includes a compression spring 61. The two ends of the compression spring 61 are respectively pressed on the push ring 62 and the spring seat 63. The stationary ring 6 is installed on the push ring 62. The push ring 62 is clamped in the guide groove 24 on the inner wall of the sealing box 2. Under the guidance of the guide groove 24, the push ring 62 can only move axially along the sealing box 2. The spring seat 63 is fixed on the inner wall of the sealing box 2. Under the action of the compression spring 61, the stationary ring 6 is always in contact and sealed with the dynamic ring 5. The second sealing mechanism includes a second sealing ring 64, which is arranged between the outer wall of the stationary ring 6 and the inner wall of the sealing box 2.

[0025] In this embodiment, a sealing packing 8 is provided between the shaft sleeve 1 and the connecting seat 3, and the two ends of the sealing packing 8 are respectively clamped between the retaining ring 32 and the packing bushing 81, the retaining ring 32 is provided on the connecting seat 3, the packing bushing 81 is clamped on the packing seat 82, the packing seat 82 is sleeved outside the shaft sleeve 1 and is sealed and clamped on the inner wall of the sealing box 2. A lip seal ring 83 is provided between the packing seat 82 and the shaft sleeve 2, and the lip seal ring 83 is clamped between the packing seat 82 and the packing bushing 81. The sealing packing 8 and the lip seal ring 83 not only play a sealing role, but also play a good heat insulation role, so as to effectively protect the dynamic ring 5 and the static ring 6, so that the seal between the two remains stable and reliable.

[0026] In this embodiment, a heat-insulating gap 26 is provided between the moving ring seat 51 and the packing seat 82, and installation gaps are left between the outer wall of the moving ring seat 51 and the inner wall of the sealing box 2, and between the sealing position of the moving ring 5 and the static ring 6 and the inner wall of the sealing box 2. The heat-insulating gap 26 is connected with the installation gap to form a heat-insulating sealed chamber 20. The sealing box 2 is provided with an air inlet 22 connected to a high-pressure gas source, and the air inlet 22 is connected with the heat-insulating sealed chamber 20. The setting of the heat-insulating sealed chamber 20 can prevent the heat in the equipment cylinder from being directly transferred to the moving ring 5 and the static ring 6 through the connecting seat 3 and the packing seat 82, thereby destroying the seal between the two. In addition, high-pressure gas such as nitrogen can also be passed into the heat-insulating sealed chamber 20 from the air inlet 22, so that the heat-insulating sealed chamber 20 maintains a positive pressure, so as to prevent the medium in the equipment cylinder from flowing out through the sealing packing 8 and the lip seal ring 83 when the sealing of the sealing packing 8 and the lip seal ring 83 fails, thereby effectively improving the sealing effect.

[0027] In this embodiment, an annular cooling chamber 23 is provided in the body of the sealing box 2, and a cooling medium inlet 231 and a cooling medium outlet 232 are provided on the cooling chamber 23, and the cooling chamber 23 is located outside the sealing position of the static ring 6 and the dynamic ring 5. During operation, a cooling medium, such as cooling water, can be introduced through the cooling medium inlet 231, so as to cool down the entire mechanical seal, especially effectively cool the dynamic ring 5 and the static ring 6, reduce the working temperature of the dynamic ring 5 and the static ring 6, so as to improve the sealing effect and prolong the effective sealing time.

[0028] The sealing box medium end 21 is sealingly supported on the connecting seat 3, and specifically, a fourth sealing ring 212 is provided between the sealing box medium end 21 and the connecting seat 3. A spherical joint connection structure is adopted between the sealing box medium end 21 and the connecting seat 3, and the spherical joint connection structure makes the sealing box medium end 21 and the connecting seat 3 inseparable, and the connecting seat 3 can make a universal rotation relative to the sealing box medium end 21. The purpose of the universal rotation of the connecting seat 3 on the sealing box medium end 21 is that when the equipment cylinder expands due to heat, the deformation of the connecting seat 3 is released and will not affect the sealing box 2. A limiting mechanism for limiting the sealing box medium end 21 to rotate with the shaft sleeve 1 is also provided between the sealing box medium end 21 and the connecting seat 3, and the limiting mechanism leaves room for the connecting seat 3 to make a universal rotation relative to the sealing box medium end 21.

[0029] Specifically, the spherical joint connection structure between the sealing box medium end 21 and the connecting seat 3 includes: the outer side wall 211 of the sealing box medium end 21 is a spherical surface, and a connecting groove 31 is provided on the connecting seat 3 located on one side of the sealing box 2. The inner side wall of the connecting groove 31 is a spherical surface that matches the outer side wall 211 of the sealing box medium end 21. The sealing box medium end 21 is wrapped and blocked by the connecting groove 31, and a rotation gap 30 is reserved between the groove bottom of the connecting groove 31 and the end of the sealing box medium end 21 for the connecting seat 3 to perform universal rotation relative to the sealing box medium end 21.

[0030] The connection groove 31 includes a first connection groove 311 and a second connection groove 312 which are connected. The inner side walls of the first connection groove 311 and the second connection groove 312 are spherical surfaces that match the outer wall of the sealing box medium end 21. The first connection groove 311 is opened on the connection seat 3, and the second connection groove 312 is arranged on the inner wall of the locking ring 7. The locking ring 7 is fixed on the connection seat 3 outside the first connection groove 311. The sealing box medium end 21 can directly extend into the first connection groove 311, and the locking ring 7 blocks the sealing box medium end 21 in the first connection groove 311 and the second connection groove 312. The purpose of adopting the connection groove 31 of the split structure is to greatly facilitate the installation between the sealing box medium end 21 and the connection seat 3. The locking ring 7 effectively ensures that the sealing box medium end 21 and the connection groove 31 are not separated.

[0031] The structure of the limiting mechanism includes: at least one limiting groove 71 is formed on the inner wall of the locking ring 7, and a limiting pin 72 is arranged in each limiting groove 71. The limiting pin 72 is arranged on the medium end 21 of the sealing box, and a gap is left between the limiting pin 72 and the limiting groove 71 for the connection seat 3 to perform universal rotation relative to the medium end 21 of the sealing box. The cooperation between the limiting pin 72 and the limiting groove 71 can limit the rotation of the sealing box 2 around the shaft sleeve 1.

[0032] The connecting groove 31 may also adopt an integral structure. In order to install the sealing box medium end 21 into the connecting groove 31, the sealing box medium end 21 may be cooled first to reduce the volume of the sealing box medium end 21 before installing it into the connecting groove 31. The limiting mechanism under this structure may directly open a limiting groove on the inner side wall of the connecting groove 31, and a limiting pin may be provided on the sealing box medium end 21.

[0033] In this embodiment, a sliding bearing 9 is arranged between the atmospheric end 22 of the sealing box and the sleeve 1, the inner ring 91 of the sliding bearing 9 is fixed to the outer wall of the sleeve 1, the outer ring 92 of the sliding bearing 9 is fixed to the inner wall of the sealing box 2, and a sliding gap 90 is left between the gland 4 and the inner ring 91 of the sliding bearing 9, leaving room for the axial displacement of the sleeve 1 relative to the sealing box 2. The sliding bearing 9 is arranged between the sealing box 2 and the sleeve 1, the purpose of which is that when the rotating shaft 100 is axially deformed after being heated, the sleeve 1 on the rotating shaft 100 can be axially displaced relative to the sealing box 2, so that the sleeve 1 releases the deformation in the axial direction.

[0034] The end of the sleeve 1 outside the gland 4 is provided with a fixing mechanism for fixing the sleeve 1 on the rotating shaft, and the structure of the fixing mechanism includes: a fastening ring 11 with a notch 110, and the notch makes the fastening ring 11 not closed in the circumferential direction, that is, similar to a clamp structure. The fastening ring 11 includes a fastening ring body 111, and a fastening cone 112 is provided on the fastening ring body 111. The outer wall diameter of the fastening cone 112 gradually decreases from away from the sleeve 1 to close to the sleeve 1. The end of the sleeve 1 is provided with a connecting ring 12, and the end of the sleeve 1 is provided with a conical pipe section 13 with a diameter gradually reduced from the outside to the inside; the fastening cone 112 extends into the conical pipe section 13, and the fastening ring body 111 and the connecting ring 12 are tightened and fixed by a fastening bolt 14. The fastening ring body 111 and the connecting ring 12 are locked and fixed, so that the fastening cone 112 can continuously move into the tapered pipe section 13, so that the fastening ring 11 is tightly fixed on the rotating shaft 100, and the sleeve 1 and the fastening cone 112 are expanded and fixed. The structure is simple, the connection is reliable, and the installation is convenient.

[0035] The advantages of the present invention are: 1. The sealing box 2 is supported on the connecting seat 3, and a spherical joint connection structure is adopted between the sealing box medium end 21 and the connecting seat 3. The spherical joint connection structure ensures that the sealing box medium end 21 and the connecting seat 3 are not separated, and the connecting seat 3 can make a universal rotation relative to the sealing box medium end 21. This allows the deformation of the connecting seat 3 to be released when the equipment cylinder expands due to heat without affecting the sealing box 2, thereby ensuring that the static ring 6 and the dynamic ring 5 installed on the inner wall of the sealing box 2 always maintain a good sealing state, that is, during this process, the static ring 6 and the dynamic ring 5 always maintain a stable, reliable and effective sealing state. Second, since a sliding bearing 9 is arranged between the sleeve 1 and the sealing box 2, when the rotating shaft 100 is heated and axially deformed, the sleeve 1 and the inner ring 91 of the sliding bearing 9 are axially displaced relative to the sealing box 2 in the direction away from the equipment cylinder, so that the rotating shaft 100 releases the axial deformation after being heated. In this process, the dynamic ring 5 and the dynamic ring seat 51 on the sleeve 1 will move axially synchronously with the sleeve 1 and compress the compression spring 61. Since the sealing box 2 is limited by the spherical joint connection structure and the limit pin, the sealing box 2 does not rotate or axially displace, so the seal between the dynamic ring 5 and the static ring 6 always maintains a reliable and effective state in this process. Third, a sliding bearing 9 is arranged between the sleeve 1 and the sealing box 2, so that the rotating shaft 100, the sleeve 1 and the components connected to the sleeve 1 are supported on the connecting seat 3 through the sliding bearing 9 and the sealing box 2, which greatly simplifies the support structure of the entire rotating shaft 100, thereby effectively reducing the equipment installation cost. 4. Based on advantages 1 and 2, the seal can not only better meet the sealing requirements under normal working conditions, but also be suitable for sealing under conditions where the temperature inside the equipment cylinder reaches high or even ultra-high temperatures, such as sealing under conditions where the temperature of the equipment cylinder reaches 650°C. When the seal described in the present invention is used under such ultra-high temperature conditions, an effective sealing state is always maintained between the dynamic ring and the static ring. Therefore, the seal described in the present invention has a wider range of applications, the sealing effect is effectively improved, and the service life of the seal is greatly extended.

Claims

1. Cartridge mechanical seals, including: The shaft sleeve is provided with a sealing box outside the shaft sleeve, and the two ends of the sealing box are respectively a sealing box medium end and a sealing box atmospheric end, and a connecting seat and a pressure cover are respectively provided on the outer sides of the sealing box medium end and the sealing box atmospheric end, and the pressure cover is fixed to the sealing box atmospheric end, and a dynamic ring assembly including a dynamic ring and a static ring assembly including a static ring are provided between the sealing box and the shaft sleeve, and the dynamic ring assembly is connected to the shaft sleeve and rotates synchronously with the shaft sleeve, and a first sealing mechanism is provided between the dynamic ring assembly and the outer wall of the shaft sleeve, and the static ring assembly is installed on the inner wall of the sealing box, and a second sealing mechanism is provided between the static ring assembly and the inner wall of the sealing box, and a compensation mechanism is also provided between the static ring assembly and the sealing box, and under the action of the compensation mechanism, the dynamic ring and the static ring are always in contact and sealed, and it is characterized in that: the sealing support of the medium end of the sealing box is on the connecting seat, and a spherical joint connection structure is adopted between the medium end of the sealing box and the connecting seat, and the spherical joint connection structure makes the medium end of the sealing box and the connecting seat not separated, and the connecting seat can make a universal rotation relative to the medium end of the sealing box, and a useful A limiting mechanism for limiting the rotation of the sealing box following the shaft sleeve; a spherical joint connection structure between the sealing box medium end and the connecting seat includes: the outer side wall of the sealing box medium end is a spherical surface, and a connecting groove is provided on the connecting seat located on one side of the sealing box medium end, and the inner side wall of the connecting groove is a spherical surface that matches the outer side wall of the sealing box medium end, and the spherical surface of the sealing box medium end is wrapped and blocked by the connecting groove, and a rotation gap is left between the groove bottom of the connecting groove and the end of the sealing box medium end for the connecting seat to make a universal rotation relative to the sealing box medium end; the connecting groove includes a first connecting groove and a second connecting groove that are connected, and the inner side walls of the first connecting groove and the second connecting groove are respectively spherical surfaces that match the outer wall of the sealing box medium end, the first connecting groove is opened on the connecting seat, and the second connecting groove is arranged on the inner wall of the locking ring, and the locking ring is fixed on the connecting seat outside the first connecting groove, and the sealing box medium end can be directly inserted into the first connecting groove, and the locking ring blocks the sealing box medium end in the first connecting groove and the second connecting groove.

2. The cartridge mechanical seal according to claim 1, characterized in that: The structure of the limiting mechanism includes: at least one limiting groove is opened on the inner wall of the connecting groove, and a limiting pin is arranged in each limiting groove. The limiting pin is arranged on the medium end of the sealing box, and a gap is left between the limiting pin and the limiting groove for the connecting seat to perform universal rotation relative to the medium end of the sealing box.

3. The cartridge mechanical seal according to claim 2, characterized in that: The limiting groove is arranged on the inner wall of the locking ring.

4. The cartridge mechanical seal according to claim 1, 2 or 3, characterized in that: The dynamic ring assembly also includes a dynamic ring seat, which is fixedly sleeved on the shaft sleeve, and the dynamic ring is installed on the dynamic ring seat, and the dynamic ring and the dynamic ring seat are sealed; the first sealing mechanism includes a first sealing ring, and the first sealing ring is arranged between the dynamic ring seat and the outer wall of the shaft sleeve.

5. The cartridge mechanical seal according to claim 4, characterized in that: The stationary ring assembly also includes a push ring, and the compensation mechanism includes a compression spring. The two ends of the compression spring are respectively pressed on the push ring and the spring seat. The stationary ring is installed on the push ring, and the push ring is clamped in the guide groove on the inner wall of the sealing box. Under the guidance of the guide groove, the push ring can only move axially along the sealing box. The spring seat is fixed on the inner wall of the sealing box. Under the action of the compression spring, the stationary ring is always in contact and sealed with the dynamic ring; the second sealing mechanism includes a second sealing ring, and the second sealing ring is sealed between the outer wall of the stationary ring and the inner wall of the sealing box.

6. The cartridge mechanical seal according to claim 5, characterized in that: A sealing packing is arranged between the shaft sleeve and the connecting seat, and the two ends of the sealing packing are respectively clamped between the retaining ring and the packing bushing, the retaining ring is arranged on the connecting seat, the packing bushing is arranged on the packing seat, the packing seat is sleeved outside the shaft sleeve and the seal is clamped on the inner wall of the sealing box; a lip seal ring is arranged between the packing seat and the shaft sleeve, and the lip seal ring is clamped between the packing seat and the packing bushing.

7. The cartridge mechanical seal according to claim 6, characterized in that: An insulating gap is arranged between the moving ring seat and the packing seat, and installation gaps are reserved between the moving ring seat and the inner wall of the sealing box, and between the sealing positions of the moving ring and the static ring and the inner wall of the sealing box. The insulating gap and the installation gap are connected to form an insulating sealed chamber; an air inlet connected to a high-pressure gas source is arranged on the sealing box, and the air inlet is connected to the insulating sealed chamber.

8. The cartridge mechanical seal according to claim 1, 2 or 3, characterized in that: A sliding bearing is arranged between the atmospheric end of the sealing box and the sleeve, the inner ring of the sliding bearing is fixed to the outer wall of the sleeve, the outer ring of the sliding bearing is fixed to the inner wall of the sealing box, and a sliding gap is reserved between the pressure cover and the inner ring of the sliding bearing for axial displacement of the sleeve relative to the sealing box.

9. The cartridge mechanical seal according to claim 1, 2 or 3, characterized in that: A fixing mechanism for fixing the sleeve on the rotating shaft is arranged at the end of the sleeve outside the gland, and the structure of the fixing mechanism includes: a fastening ring with a notch, the notch makes the fastening ring not closed in the circumference, the fastening ring includes a fastening ring body, a fastening cone is connected to the fastening ring body, the outer wall diameter of the fastening cone gradually decreases from away from the sleeve to close to the sleeve, a connecting ring is arranged at the end of the sleeve, and a conical pipe section with a diameter gradually decreasing from the outside to the inside is arranged at the end of the sleeve; the fastening cone extends into the conical pipe section, and the fastening ring body and the connecting ring are tightened and fixed by fastening bolts.

10. The cartridge mechanical seal according to claim 1, 2 or 3, characterized in that: A cooling chamber is arranged in the body of the sealing box, and a cooling medium inlet and a cooling medium outlet are arranged on the cooling chamber. The cooling chamber is located outside the sealing position of the dynamic ring and the static ring.

11. The cartridge mechanical seal according to claim 1, 2 or 3, characterized in that: A plurality of sealing grooves are arranged at intervals in the axial direction of the inner wall of the shaft sleeve, and a third sealing ring is arranged in each sealing groove.

Images