CN113324037A

CN113324037A - Combined mechanical sealing device for kneading reactor

Info

Publication number: CN113324037A
Application number: CN202110781417.6A
Authority: CN
Inventors: 杨胜华; 刘凯; 刘绍川; 杨岳
Original assignee: Jiangsu Sunkaier Industrial Technology Co ltd
Current assignee: Jiangsu Sunkaier Industrial Technology Co ltd
Priority date: 2021-07-11
Filing date: 2021-07-11
Publication date: 2021-08-31

Abstract

The invention discloses a combined mechanical sealing device for a kneading reactor, which comprises a sealing shaft sleeve (2), a sealing gland component (16), a sealing static ring seat (14), a mechanical sealing seat (10), a sealing bearing seat (7), a sealing bearing gland (5), a static ring (20), a sealing dynamic ring (24) and a deep groove ball bearing (6), wherein the sealing shaft sleeve is arranged on a shaft, and the sealing gland component is characterized in that: the outer wall of one end of the sealing shaft sleeve (2) corresponding to the sealing gland component (16) is provided with a reverse thread (36), and a cavity formed by the sealing gland component (16) and the sealing shaft sleeve (2) where the reverse thread (36) is located is internally provided with a sealing reverse pushing sleeve (19) matched with the reverse thread (36). The sealing device prevents materials from entering the sealing device through the arrangement of the reverse threads, and the sealing reverse pushing sleeve matched with the reverse threads can further improve the sealing performance; and the sealing device is able to accommodate axial movement due to thermal expansion.

Description

Combined mechanical sealing device for kneading reactor

Technical Field

The invention relates to the technical field of kneading reactors, in particular to a combined mechanical sealing device for a kneading reactor.

Background

Mechanical seal is widely used for mechanical stirring sealing device, nevertheless because by seal structure restriction, to some operating modes, for example operating modes such as high temperature, height, polymerization, along with the rising of temperature, the axle can take place expend with heat and contract with cold because of the rising of temperature, leads to sealed face inefficacy, reveals for the material gets into in the mechanical seal.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provide a combined mechanical sealing device for a kneading reactor.

The invention aims to solve the problems by the following technical scheme:

the utility model provides a combination formula mechanical seal device for kneading reactor, is including setting up at epaxial sealed axle sleeve, gland subassembly, sealed stationary ring seat, mechanical seal seat, sealed bearing frame, sealed bearing gland and stationary ring, sealed rotating ring and deep groove ball bearing, its characterized in that: the outer wall of one end of the sealing shaft sleeve corresponding to the sealing gland component is provided with a reverse thread, and a sealing reverse pushing sleeve matched with the reverse thread is arranged in a cavity formed by the sealing gland component where the reverse thread is located and the sealing shaft sleeve.

The inner side of the sealing gland assembly and the outer wall of the sealing shaft sleeve form a packing cavity and a material leakage cavity, and the cavity where the sealing reverse thrust sleeve is located and the material leakage cavity are respectively located on two axial sides of the packing cavity; and a leakage discharge hole which can be opened is formed in the sealing gland component where the leakage cavity is located.

The cavity body where the packing cavity and the sealing reverse pushing sleeve are located is separated by a sealing gland component and a sealing shaft sleeve in a direct contact mode, a sealing packing compression ring is arranged in the axial direction of the polytetrafluoroethylene fiber woven packing and the polytetrafluoroethylene fiber woven packing, the opening of the packing cavity is sealed by a packing spring seat with a cylindrical spiral compression spring II, one end of the cylindrical spiral compression spring II arranged in the axial direction is embedded into the packing spring seat, and the other end of the cylindrical spiral compression spring II abuts against the sealing packing compression ring.

A rotary GREEN ring is arranged in the cavity of the sealing packing compression ring, the inner wall of the rotary GREEN ring is in contact with the outer wall of the sealing shaft sleeve, and an O-shaped rubber sealing ring seven for sealing is arranged between the outer wall of the sealing packing compression ring and the corresponding inner wall of the sealing gland assembly.

The sealing device is characterized in that a sealing spring seat fixed on the outer wall of the sealing shaft sleeve is arranged in a cavity formed between the mechanical sealing seat and the outer wall of the sealing shaft sleeve, two axial sides of the sealing spring seat are respectively provided with one end of a sealing movable ring and the other end of the sealing movable ring in a positioning mode, and the static rings are respectively and correspondingly arranged in the cavity formed by the sealing static ring seat and the sealing shaft sleeve and the cavity formed by the sealing bearing seat and the sealing shaft sleeve.

The outer side of the sealing spring seat is provided with a movable ring nest which is embedded in an axially concave-convex mode, the sealing spring seat and the movable ring nest are fixed on the outer wall of the sealing shaft sleeve through an inner hexagonal cylinder end fastening screw, a first cylindrical helical compression spring is arranged in a cavity of the sealing spring seat facing the sealing bearing seat, one end of the first cylindrical helical compression spring is embedded at the bottom of the cavity of the sealing spring seat, and the other end of the first cylindrical helical compression spring abuts against the corresponding movable ring nest.

And a rotary Gray ring is adopted for sealing between the inner wall of the sealed static ring seat, which is in contact with the sealed shaft sleeve, and the outer wall of the corresponding sealed shaft sleeve.

The sealing shaft sleeve is provided with a sealing shaft cover, a sealing shaft sleeve mounting step is arranged on the inner wall of the sealing shaft sleeve, and the sealing shaft cover is provided with a sealing shaft sleeve.

The axial length of the axial adjusting groove is 50 mm-80 mm.

The inner wall of the sealing shaft sleeve is provided with a shaft sleeve adjusting step, the outer wall of the shaft is provided with a shaft wall adjusting step opposite to the shaft sleeve adjusting step, and the shaft wall adjusting step and the shaft sleeve adjusting step are concave-convex complementary.

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

the sealing device prevents materials from entering the sealing device through the arrangement of the reverse threads, and the sealing reverse pushing sleeve matched with the reverse threads can further improve the sealing performance; through the arrangement of the material leaking cavity and the material leaking hole, when materials still can enter the material leaking cavity through sealing components such as the reverse threads, the sealing reverse pushing sleeve, the polytetrafluoroethylene fiber woven packing, the packing spring seat and the like, the materials in the material leaking cavity are discharged or drawn out through the material leaking hole which can be sealed on the material leaking cavity after being accumulated for a period of time; the sealing device can stably and controllably move axially through the arrangement of the flat key, the matched axial adjusting groove, the shaft sleeve mounting step, the shaft wall adjusting step and the shaft sleeve adjusting step, so as to compensate the axial displacement of the sealing device caused by thermal expansion.

Drawings

FIG. 1 is a schematic structural view of a combined mechanical seal device for a kneading reactor of the present invention;

fig. 2 is a schematic view of the state of the movable ring nests of the invention which are embedded in a concave-convex manner.

Wherein: 1-a flat bond; 2, sealing the shaft sleeve; 3, a pin shaft; 4-elastic retainer ring for shaft; 5, sealing a bearing gland; 6-deep groove ball bearing; 7, sealing the bearing seat; 8-O type rubber seal ring I; 9-O type rubber seal ring II; 10-mechanical seal seat; 11-a cylindrical helical compression spring I; 12-a sealing spring seat; 13-a cylindrical helical compression spring II; 14, sealing a static ring seat; 15-packing spring seats; 16-a gland assembly; 17-sealing the packing compression ring; 18-polytetrafluoroethylene fiber braided packing; 19-sealing and reversely pushing the sleeve; 20-stationary ring; 21-O type rubber seal ring III; a 22-O type rubber sealing ring IV; a fifth 23-O-shaped rubber sealing ring; 24-sealing movable ring; 241-nesting the movable ring; 242 — cylindrical pin; 25-set screws; 26-O type rubber seal ring six; 27-rotating the Glare circle; a 28-O type rubber seal ring seven; eight 29-O type rubber sealing rings; 30-axial adjustment groove; 31-shaft wall adjusting step; 32-shaft sleeve adjusting step; 33-step for mounting shaft sleeve; 34-a material leaking cavity; 35-a leakage discharge hole; 36-reverse thread.

Detailed Description

The invention is further described with reference to the following figures and examples.

As shown in fig. 1: a combined mechanical sealing device for a kneading reactor comprises a sealing shaft sleeve 2, a sealing gland component 16, a sealing static ring seat 14, a mechanical sealing seat 10, a sealing bearing seat 7, a sealing bearing gland 5, a static ring 20, a sealing movable ring 24 and a deep groove ball bearing 6 which are arranged on a shaft, wherein the outer wall of one end of the sealing shaft sleeve 2 corresponding to the sealing gland component 16 is provided with a reverse thread 36, and materials are prevented from entering the sealing device through the arrangement of the reverse thread 36; and a cavity formed by the sealing gland component 16 and the sealing shaft sleeve 2 where the reverse thread 36 is positioned is internally provided with a sealing reverse pushing sleeve 19 matched with the reverse thread 36, and the sealing reverse pushing sleeve 19 is limited by an elastic check ring for holes so as to further improve the sealing performance.

As shown in fig. 1: a packing cavity and a material leakage cavity 34 are formed on the inner side of the sealing gland component 16 and the outer wall of the sealing shaft sleeve 2, and the cavity where the sealing reverse pushing sleeve 19 is located and the material leakage cavity 34 are respectively located on the two axial sides of the packing cavity; the cavity where the packing cavity and the sealing reverse pushing sleeve 19 are located is separated by direct contact of a sealing gland assembly 16 and a sealing shaft sleeve 2, polytetrafluoroethylene fiber woven packing 18 is filled in the packing cavity, a sealing packing press ring 17 is arranged in the axial direction of the polytetrafluoroethylene fiber woven packing 18, the opening of the packing cavity is sealed by a packing spring seat 15 with a cylindrical spiral compression spring II 13, one end of the cylindrical spiral compression spring II 13 arranged in the axial direction is embedded in the packing spring seat 15, and the other end of the cylindrical spiral compression spring II is abutted against the sealing packing press ring 17; a rotary GREEN 27 is arranged in the cavity of the sealing packing press ring 17, the inner wall of the rotary GREEN 27 is in contact with the outer wall of the sealing shaft sleeve 2, and an O-shaped rubber sealing ring seven 28 for sealing is arranged between the outer wall of the sealing packing press ring 17 and the corresponding inner wall of the sealing gland assembly 16; an openable material discharge hole 35 is formed in the gland assembly 16 where the material discharge chamber 34 is located, and the material accumulated in the material discharge chamber 34 is discharged by opening the material discharge hole 35.

As shown in fig. 1 and 2: furthermore, a sealing spring seat 12 fixed on the outer wall of the sealing shaft sleeve 2 is arranged in a cavity formed between the mechanical sealing seat 10 and the outer wall of the sealing shaft sleeve 2, a movable ring nest 241 which is embedded in a concave-convex manner along the axial direction is arranged on the outer side of the sealing spring seat 12, two movable ring nests 241 arranged along the axial direction are sleeved outside the sealing spring seat 12, the sealing spring seat 12 and the movable ring nest 241 are fixed on the outer wall of the sealing shaft sleeve 2 through a hexagon socket head cap screw 25 (the protruding part of the movable ring nest 241 is used for fixing a set screw 25, the set screw 25 is only embodied on the movable ring nest 241 on the lower side in the axial direction in figure 1 due to the position of the cross section in figure 1), a cylindrical helical compression spring 11 is arranged in the cavity of the sealing spring seat 12 facing the sealing shaft bearing 7, and the cylindrical helical compression spring 11 plays a compensation role after a friction pair formed by the sealing static ring 20 and the sealing movable ring 24 is worn, one end of the first cylindrical helical compression spring 11 is embedded at the bottom of the cavity of the sealing spring seat 12, and the other end of the first cylindrical helical compression spring abuts against the corresponding movable ring nesting 241; for the sealing movable ring 24, one end of the sealing movable ring 24 is respectively embedded in the axial two-side cavity formed by the sealing spring seat 12 and the movable ring nesting 241, the other end of the sealing movable ring 24 is respectively and correspondingly provided with the static ring 20, and the inner side of the movable ring nesting 241 is provided with the cylindrical pin 242 for further limiting the sealing movable ring 24; the static ring 20 is respectively embedded in a cavity formed by the sealing static ring seat 14 and the sealing shaft sleeve 2 and a cavity formed by the sealing shaft bearing seat 7 and the sealing shaft sleeve 2; in addition, a rotary Gray ring 27 is adopted for sealing between the inner wall of the static sealing ring seat 14, which is in contact with the sealing shaft sleeve 2, and the outer wall of the corresponding sealing shaft sleeve 2.

Specifically, six grooves are axially and uniformly distributed on the outer part of the seal shaft sleeve 2 along the circumferential direction of the shaft, six internal hexagonal cylindrical end set screws 25 penetrate through a movable ring nesting 241 for embedding the seal movable ring 24 and a corresponding insertion groove of the seal spring seat 12 one by one, and at the moment, the movable ring nesting 241 and the seal spring seat 12 are fixed on the outer wall of the seal shaft sleeve 2 through the internal hexagonal cylindrical end set screws 25. When the mechanical sealing device slides on the sealing shaft sleeve 2, the inner hexagonal cylinder end fastening screw 25 can play a positioning role, and the structure meets the requirements of the mechanical sealing device during the cold and hot deformation of the shaft.

On the basis of the sealing structure, a structure that the sealing device can move axially can be provided, so as to compensate the axial displacement of the sealing device caused by thermal expansion. The concrete structure is as follows: a pin shaft 3 is arranged at one end of the sealing shaft sleeve 2 corresponding to the sealing bearing gland 5, an axial adjusting groove 30 with the axial length of 50 mm-80 mm is formed in the outer wall of the shaft where the pin shaft 3 is located, a shaft sleeve mounting step 33 is formed in the inner wall of the sealing shaft sleeve 2, a flat key mounting groove formed by the axial adjusting groove 30 and the shaft sleeve mounting step 33 is used for embedding a flat key 1, and the pin shaft 3 penetrates through the sealing shaft sleeve 2 and is fixedly connected with the flat key 1 to limit the relative position of the shaft and the sealing shaft sleeve 2; in order to match the axial displacement of the flat key 1 and play a role in limiting, the inner wall of the sealing shaft sleeve 2 is provided with a shaft sleeve adjusting step 32, the outer wall of the shaft is provided with a shaft wall adjusting step 31 opposite to the shaft sleeve adjusting step 32, and the shaft wall adjusting step 31 and the shaft sleeve adjusting step 32 are concave-convex complementary.

Example one

As shown in fig. 1, the components required for the combined mechanical seal device for the kneading reactor include: a flat key 1, a sealing shaft sleeve 2, a pin shaft 3, a shaft circlip 4, a sealing bearing gland 5, a deep groove ball bearing 6, a sealing bearing seat 7, a first O-shaped rubber seal ring 8, a second O-shaped rubber seal ring 9, a mechanical sealing seat 10, a first cylindrical spiral compression spring 11, a sealing spring seat 12, a second cylindrical spiral compression spring 13, a static sealing ring seat 14, a packing spring seat 15, a sealing gland component 16, a sealing packing press ring 17, a polytetrafluoroethylene fiber braided packing 18, a sealing reverse push sleeve 19, a static ring 20, a third O-shaped rubber seal ring 21, a fourth O-shaped rubber seal ring 22, a fifth O-shaped rubber seal ring 23, a dynamic sealing ring 24, an inner cylindrical end set screw 25, a sixth O-shaped rubber seal ring 26, a rotary Glare ring 27, a seventh O-shaped rubber seal ring 28, an eighth O-shaped rubber seal ring 29, an axial adjusting groove 30, a shaft wall adjusting step 31, a shaft sleeve adjusting step 32, a deep groove and a deep groove, The sleeve mounts the step 33. A sealing shaft sleeve 2 is sleeved on the shaft, one end of the inner wall of the sealing shaft sleeve 2 and one end of the outer wall of the shaft are sealed by an O-shaped rubber sealing ring eight 29, and the other end of the inner wall of the sealing shaft sleeve 2 and the other end of the outer wall of the shaft are sealed by an O-shaped rubber sealing ring three 21; at the position of the eight 29O-shaped rubber sealing ring, a sealing gland component 16 with a cooling liquid cavity is sleeved outside the sealing shaft sleeve 2, a sealing reverse pushing sleeve 19 is arranged in a cavity below the contact part of the sealing gland component 16 and the sealing shaft sleeve 2, and a filling cavity is formed by a cavity above the contact part; the outer wall of the sealing shaft sleeve 2 where the sealing reverse pushing sleeve 19 is located is provided with a reverse thread 36, the reverse thread 36 can prevent materials from entering the sealing device, and the matching structure of the sealing reverse pushing sleeve 19 and the reverse thread 36 improves the sealing performance; the filling cavity is filled with polytetrafluoroethylene fiber braided filling 18, and a sealing filling compression ring 17 is arranged above the polytetrafluoroethylene fiber braided filling 18; a rotary GREEN 27 is arranged in the cavity of the sealing packing press ring 17, the inner wall of the rotary GREEN 27 is in contact with the outer wall of the sealing shaft sleeve 2, and an O-shaped rubber sealing ring seven 28 for sealing is arranged between the outer wall of the sealing packing press ring 17 and the corresponding inner wall of the sealing gland assembly 16; a packing spring seat 15 for sealing the packing cavity is arranged above the packing compression ring 17, the lower end of a second cylindrical helical compression spring 13 embedded in the packing spring seat 15 is abutted against the upper end of the packing compression ring 17, and the second cylindrical helical compression spring 13 is arranged to provide an axial moving space for polytetrafluoroethylene fiber braided packing 18; the axial upside of the packing spring seat 15 forms a material leakage cavity 34, when materials still can enter the material leakage cavity 34 through the reverse threads 36 and sealing parts such as the sealing reverse pushing sleeve 19, the polytetrafluoroethylene fiber woven packing 18, the packing spring seat 15 and the like, and the materials in the material leakage cavity 34 are accumulated for a period of time and then are discharged through a material discharge hole 35 which can be sealed on the material leakage cavity 34. A sealing static ring seat 14 is sleeved above the sealing gland component 16, a mechanical sealing seat 10 is arranged above the sealing static ring seat 14, a sealing bearing seat 7 is arranged above the mechanical sealing seat 10, and corresponding O-shaped rubber sealing rings two 9 are respectively adopted for sealing between the contact surfaces of the sealing static ring seat 14 and the sealing gland component 16, between the contact surfaces of the sealing static ring seat 14 and the mechanical sealing seat 10 and between the contact surfaces of the mechanical sealing seat 10 and the sealing bearing seat 7; a static ring 20 is arranged in a cavity formed by the inner side of the sealed static ring seat 14 and the outer wall of the sealed shaft sleeve 2, an O-shaped rubber sealing ring I8 is adopted for sealing between the outer side of the static ring 20 and the inner side of the sealed static ring seat 14, and a rotary Glare ring 27 is adopted for sealing between the inner wall of the sealed static ring seat 14 below the static ring 20 and the outer wall of the sealed shaft sleeve 2; a seal moving ring 24 is arranged above the static ring 20, the upper end of the seal moving ring 24 is embedded in the seal spring seat 12, the space between the inner side of the upper part of the seal moving ring 24 and the outer side of the lower part of the seal spring seat 12 is sealed by adopting an O-shaped rubber seal ring IV 22, the outer wall of the seal shaft sleeve 2 is provided with an installation step for limiting the seal spring seat 12, the seal spring seat 12 is fixed on the outer wall of the seal shaft sleeve 2 through an inner hexagonal cylindrical end set screw 25, and the space between the upper side and the lower side of the inner wall of the seal spring seat 12 and the outer wall of the seal shaft sleeve 2 is respectively sealed by adopting an O-shaped rubber seal ring V23 and an O-shaped rubber seal ring VI 26; a cylindrical spiral compression spring I11 arranged along the axial direction is arranged in a cavity of the sealing spring seat 12, the upper end of the cylindrical spiral compression spring I11 is fixed on the lower end face of the other sealing moving ring 24 embedded in the sealing spring seat 12, and a corresponding O-shaped rubber sealing ring IV 22 is adopted for sealing between the inner side of the lower part of the sealing moving ring 24 and the outer side of the upper part of the sealing spring seat 12; another static ring 20 is also arranged above a sealing movable ring 24 which is positioned above the sealing spring seat 12 in the axial direction, the static ring 20 is embedded in a step-shaped cavity between the inner side of the sealing bearing seat 7 and the outer wall of the sealing shaft sleeve 2, and a corresponding O-shaped rubber sealing ring I8 is adopted for sealing between the outer side of the static ring 20 and the inner side of the sealing bearing seat 7; a deep groove ball bearing 6 is arranged in a cavity formed between the upper part of the sealing bearing seat 7 and the outer wall of the sealing shaft sleeve 2, the deep groove ball bearing 6 is limited in the cavity by the sealing bearing gland 5, and meanwhile, the position of the deep groove ball bearing 6 can be limited by the elastic shaft check ring 4 embedded on the outer wall of the sealing shaft sleeve 2; the sealing shaft sleeve 2 positioned on the upper side of the sealing bearing gland 5 is provided with a pin shaft 3, the pin shaft 3 can limit the flat key 1 in a flat key installation groove formed by an axial adjustment groove 30 and a shaft sleeve installation step 33, and the axial adjustment groove 30 with the length of 50-80 mm is axially arranged on the outer wall of the shaft, so that the position of the flat key installation groove can be adjusted, the axial position of the flat key 1 is further adjusted, and the axial displacement generated by thermal expansion is compensated; a shaft wall adjusting step 31 is arranged at the axial lower side of the axial adjusting groove 30, a shaft sleeve adjusting step 32 corresponding to the shaft wall adjusting step 31 is arranged on the inner wall of the shaft sleeve, and the shaft wall adjusting step 31 and the shaft sleeve adjusting step 32 are concave-convex complementary.

The rotating greige ring 27 for the shaft is a double acting high pressure rotary seal element. The sealing structure has the characteristics of good sealing performance, low friction resistance, long service life, wear resistance, no viscous phenomenon, extrusion resistance, small structural size and the like. The shaft is typically mounted in a closed channel with a rotating greige ring 27: (1) firstly, placing the O-shaped ring into the groove, and pressing the PTFE slip ring to form a core, but carefully preventing the PTFE slip ring from being broken; (2) and placing the PTFE slip ring in a pressed state on the O-shaped ring, and flattening the PTFE slip ring in the arrow direction by using a round rod (usually with 10-15 degrees) to restore the original size. Installation description: 1. sharp corners are required to be deburred, namely blunt and chamfered, and if threads are met during installation of a sealing element, protection is required to be added to prevent the sealing element from being damaged; 2. any rust, dirt, debris or foreign particles must be removed, so that the phenomena of sealing part damage, oil leakage and the like caused by dust can be prevented; 3. tools with sharp corners are not allowed to be used during installation; 4. before installation, the cylinder barrel, the rotating shaft and the seal need to be coated with lubricating oil or lubricating grease, and if the lubricating grease is used, the components of the lubricating grease cannot contain solid additives (such as molybdenum disulfide or zinc sulfide); 5. the PTFE slip ring can be heated to 80-120 ℃ in oil or water, and can expand, so that the rotary Gray ring 27 is easy to install.

The sealing device of the invention prevents the material from entering the sealing device through the arrangement of the reverse thread 36, and in addition, the sealing reverse pushing sleeve 19 matched with the reverse thread 36 can further improve the sealing performance; through the arrangement of the material leakage cavity 34 and the material leakage discharge hole 35, when the material still can enter the material leakage cavity 34 through the reverse threads 36, the sealing reverse pushing sleeve 19, the polytetrafluoroethylene fiber woven packing 18, the packing spring seat 15 and other sealing components, the material in the material leakage cavity 34 is accumulated for a period of time, and then is discharged or drawn out through the material leakage discharge hole 35 which can be closed on the material leakage cavity 34; the sealing device can stably and controllably move axially through the arrangement of the flat key 1, the matched axial adjusting groove 30, the shaft sleeve mounting step 33, the shaft wall adjusting step 31 and the shaft sleeve adjusting step 32, so as to compensate the axial displacement of the sealing device caused by thermal expansion.

The above embodiments are only for illustrating the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby, and any modification made on the basis of the technical scheme according to the technical idea proposed by the present invention falls within the protection scope of the present invention; the technology not related to the invention can be realized by the prior art.

Claims

1. The utility model provides a combination formula mechanical seal device for kneading reactor, is including setting up at epaxial sealed axle sleeve (2), gland subassembly (16), sealed stationary ring seat (14), mechanical seal seat (10), sealed bearing frame (7), sealed bearing gland (5) and stationary ring (20), sealed rotating ring (24) and deep groove ball bearing (6), its characterized in that: the outer wall of one end of the sealing shaft sleeve (2) corresponding to the sealing gland component (16) is provided with a reverse thread (36), and a cavity formed by the sealing gland component (16) and the sealing shaft sleeve (2) where the reverse thread (36) is located is internally provided with a sealing reverse pushing sleeve (19) matched with the reverse thread (36).

2. Combined mechanical seal for kneading reactors according to claim 1, characterized in that: the inner side of the sealing gland component (16) and the outer wall of the sealing shaft sleeve (2) form a packing cavity and a material leakage cavity (34), and the cavity where the sealing reverse pushing sleeve (19) is located and the material leakage cavity (34) are located on two axial sides of the packing cavity respectively; and the sealing gland component (16) where the material leakage cavity (34) is located is provided with a material leakage discharging hole (35) which can be opened.

3. Combined mechanical seal for kneading reactors according to claim 2, characterized in that: the packing cavity and the cavity where the sealing reverse pushing sleeve (19) is located are separated by a sealing gland component (16) and a sealing shaft sleeve (2) in a direct contact mode, a sealing packing pressing ring (17) is arranged in the axial direction of the packing cavity filled with polytetrafluoroethylene fiber woven packing (18) and polytetrafluoroethylene fiber woven packing (18), the opening of the packing cavity is sealed by a packing spring seat (15) with a cylindrical spiral compression spring II (13), one end of the cylindrical spiral compression spring II (13) arranged in the axial direction is embedded into the packing spring seat (15), and the other end of the cylindrical spiral compression spring II abuts against the sealing packing pressing ring (17).

4. Combined mechanical seal for kneading reactors according to claim 3, characterized in that: the sealing gland is characterized in that a rotary GREEN (27) is arranged in a cavity of the sealing gland pressing ring (17), the inner wall of the rotary GREEN (27) is in contact with the outer wall of the sealing shaft sleeve (2), and an O-shaped rubber sealing ring seven (28) for sealing is arranged between the outer wall of the sealing gland pressing ring (17) and the corresponding inner wall of the sealing gland assembly (16).

5. Combined mechanical seal for kneading reactors according to claim 1, characterized in that: the sealing device is characterized in that a sealing spring seat (12) fixed on the outer wall of the sealing shaft sleeve (2) is arranged in a cavity formed between the mechanical sealing seat (10) and the outer wall of the sealing shaft sleeve (2), one end of a sealing moving ring (24) is respectively positioned at two axial sides of the sealing spring seat (12), a static ring (20) is respectively and correspondingly arranged at the other end of the sealing moving ring (24), and the static ring (20) is respectively embedded in the cavity formed by the sealing static ring seat (14) and the sealing shaft sleeve (2) and in the cavity formed by the sealing bearing seat (7) and the sealing shaft sleeve (2).

6. Combined mechanical seal for a kneader reactor according to claim 6, characterized in that: the outer side of the sealing spring seat (12) is provided with a movable ring nesting sleeve (241) which is embedded in a concave-convex mode along the axial direction, the sealing spring seat (12) and the movable ring nesting sleeve (241) are fixed on the outer wall of the sealing shaft sleeve (2) through an inner hexagonal cylinder end set screw (25), a cylindrical helical compression spring I (11) is arranged in a cavity of the sealing spring seat (12) facing the sealing bearing seat (7), one end of the cylindrical helical compression spring I (11) is embedded at the bottom of the cavity of the sealing spring seat (12), and the other end of the cylindrical helical compression spring I abuts against the corresponding movable ring nesting sleeve (241).

7. Combined mechanical seal for a kneading reactor according to claim 1 or 5, characterized in that: the inner wall of the sealing static ring seat (14) which is contacted with the sealing shaft sleeve (2) and the outer wall of the corresponding sealing shaft sleeve (2) are sealed by a rotary Grey circle (27).

8. Combined mechanical seal for kneading reactors according to claim 1, characterized in that: one end of the sealing shaft sleeve (2) corresponding to the sealing bearing gland (5) is provided with a pin shaft (3), the outer wall of the shaft where the pin shaft (3) is located is provided with an axial adjusting groove (30), the inner wall of the sealing shaft sleeve (2) is provided with a shaft sleeve mounting step (33), a flat key mounting groove formed by the axial adjusting groove (30) and the shaft sleeve mounting step (33) is used for embedding a flat key (1), and the pin shaft (3) penetrates through the sealing shaft sleeve (2) and the flat key (1) to be fixedly connected so as to limit the relative position of the shaft and the sealing shaft sleeve (2).

9. Combined mechanical seal for kneading reactors according to claim 8, characterized in that: the axial length of the axial adjusting groove (30) is 50-80 mm.

10. Combined mechanical seal for kneading reactors according to claim 8 or 9, characterized in that: the inner wall of the sealing shaft sleeve (2) is provided with a shaft sleeve adjusting step (32), the outer wall of the shaft is provided with a shaft wall adjusting step (31) opposite to the shaft sleeve adjusting step (32), and the shaft wall adjusting step (31) and the shaft sleeve adjusting step (32) are concave-convex complementary.