CN214974891U

CN214974891U - Airtight explosion-proof piston pushes away material centrifuge

Info

Publication number: CN214974891U
Application number: CN202121159939.4U
Authority: CN
Inventors: 颜国良; 王深波; 王细检
Original assignee: Xiangtan Huibo Centrifuge Co ltd
Current assignee: Xiangtan Huibo Centrifuge Co ltd
Priority date: 2021-05-27
Filing date: 2021-05-27
Publication date: 2021-12-03
Anticipated expiration: 2031-05-27

Abstract

The invention discloses an airtight explosion-proof piston pushing centrifuge, which belongs to a piston pushing centrifuge and comprises a centrifuge body, wherein the front end of the centrifuge body is provided with a shell, a shell water inlet device is arranged on the shell, a rotary drum part is arranged in the shell, the centrifuge body comprises a bearing seat, the bearing seat is connected with a wall plate, the shell is connected to the other side of the wall plate, a hollow shaft is arranged in the bearing seat, a hollow shaft sealing assembly is arranged on the outer wall of one end of the hollow shaft, and the hollow shaft sealing assembly comprises a wall plate labyrinth ring and a hollow shaft labyrinth ring; the material pushing shaft is arranged in the hollow shaft, a material pushing shaft sealing assembly is arranged on the outer wall of one end of the material pushing shaft and comprises a sealing ring frame and a material pushing shaft sealing ring seat, an oil inlet is formed in the upper portion of the bearing seat, the oil inlet is communicated with a cavity between the bearing seat and the hollow shaft, an oil outlet hole is formed in the bottom of the bearing seat, a first oil passing hole is formed in one end of the side wall of the hollow shaft, and a second oil passing hole and a water outlet hole are formed in the other end of the side wall of the hollow shaft.

Description

Airtight explosion-proof piston pushes away material centrifuge

Technical Field

The invention relates to the technical field of piston pusher centrifuges, in particular to a closed explosion-proof piston pusher centrifuge.

Background

The horizontal piston pusher centrifuge is a continuous operation filtering centrifuge, under the condition of high-speed operation, the material is fed into the drum through the feeding pipe, and uniformly distributed on the first-stage drum screen mesh after being accelerated, and most of the liquid is filtered under the action of centrifugal force and discharged through the gap of the first-stage drum screen mesh and the liquid discharge holes on the first-stage drum and the second-stage drum. The solid particles form a filter cake on the screen. The first-stage rotary drum rotates at a high speed and moves axially in a reciprocating manner, the filter cake is pushed to the second-stage rotary drum in a pulsating manner under the action of the material pushing disc, the filter cake obtains a larger centrifugal force on the second-stage rotary drum, and residual liquid is discharged through the screen of the second-stage rotary drum and the liquid discharge holes in the second-stage rotary drum, collected by the collecting cover and then discharged out of the machine through the liquid outlet. The filter cake is pushed to the solid collecting tank by the first-stage rotary drum in a pulsating mode and is discharged out of the machine through the solid outlet. The piston pusher centrifuge can continuously complete all the operation procedures of feeding, separating, washing, drying and discharging, has the characteristics of large yield and high efficiency, and is widely applied to the departments of chemical industry, chemical fertilizer, pharmacy, food, military industry and the like.

In long-term use, the phenomenon that liquid in a rotary drum part is communicated with lubricating oil in a bearing seat easily is found, filtrate in the rotary drum part is polluted or the lubricating effect of a hollow shaft and a material pushing shaft is deteriorated, the working performance and the service life of a moving part are influenced, and in severe cases, the production quality of a product is influenced, and machine faults are easily caused.

Disclosure of Invention

The invention aims to solve the problems, and provides a sealed explosion-proof piston pusher centrifuge which is provided with a hollow shaft sealing assembly, a pusher shaft sealing assembly and other multiple sealing measures to form a plurality of labyrinth seals, so that lubricating oil and filtrate are thoroughly separated, the phenomenon of oil channeling is avoided, the product quality is guaranteed, and the normal and stable operation of the centrifuge is ensured.

In order to realize the purpose, the invention adopts the technical scheme that: an airtight explosion-proof piston pusher centrifuge comprises a centrifuge body, wherein the front end of the centrifuge body is provided with a shell, a shell water inlet device is arranged on the shell, a drum part is arranged in the shell and comprises a first-stage drum and a second-stage drum, and the airtight explosion-proof piston pusher centrifuge is characterized in that the centrifuge body comprises a bearing seat, the bearing seat is connected with a wallboard, the shell is connected to the other side of the wallboard, a hollow shaft is arranged in the bearing seat, a hollow shaft sealing assembly is arranged on the outer wall of one end of the hollow shaft, and the hollow shaft sealing assembly comprises a wallboard labyrinth ring and a hollow shaft labyrinth ring; the material pushing device is characterized in that a material pushing shaft is arranged in the hollow shaft, a material pushing shaft sealing assembly is arranged on the outer wall of one end of the material pushing shaft and comprises a sealing ring frame and a material pushing shaft sealing ring seat, an oil inlet is formed in the upper portion of the bearing seat, the oil inlet is communicated with a cavity between the bearing seat and the hollow shaft, an oil outlet is formed in the bottom of the bearing seat, a first oil passing hole is formed in one end of the side wall of the hollow shaft, and a second oil passing hole and a water outlet hole are formed in the other end of the side wall of the hollow shaft.

Furthermore, the wall board labyrinth ring is connected to the wall board through a bolt, a second sealing ring is arranged on the joint surface of the wall board labyrinth ring and the wall board labyrinth ring, and the wall board labyrinth ring is tightly attached to the outer wall of the hollow shaft for sealing; the hollow shaft labyrinth ring is connected to the bearing seat through a bolt, a third sealing ring and a sixth sealing ring are arranged on the joint surface of the bearing seat and the bearing seat, and the hollow shaft labyrinth ring is tightly attached to the outer wall of the hollow shaft for sealing; the hollow shaft labyrinth ring and the wallboard labyrinth ring are arranged at intervals.

Further, the hollow shaft outer wall is sleeved with a hollow shaft bushing, the outer surface of the hollow shaft bushing is provided with a plurality of protrusions and is in a sawtooth shape, and the hollow shaft labyrinth ring and the wall plate labyrinth ring are both tightly matched with the outer surface of the hollow shaft bushing in a pasting mode to seal.

Furthermore, one side of the hollow shaft labyrinth ring opposite to the wallboard labyrinth ring is provided with a high-speed oil seal, the high-speed oil seal is limited by an oil seal gland respectively, and the oil seal gland is connected to the side face of the hollow shaft labyrinth ring or the wallboard labyrinth ring through a bolt.

Furthermore, the sealing ring frame is connected to the second-stage rotary drum bottom plate through bolts, and the pushing shaft sealing ring seat is connected to the hollow shaft through a long bolt; the outer wall of the front end of the pushing shaft is provided with a pushing shaft bushing, and the sealing ring frame and the pushing shaft sealing ring seat are closely matched with the outer surface of the pushing shaft bushing for sealing.

Furthermore, a GREEN ring is arranged at the joint sealing surface of the sealing ring frame and the pushing bushing, and a fourth sealing ring is arranged at the joint surface of the sealing ring frame and the secondary drum bottom plate; and a Y-shaped sealing ring is arranged at the joint sealing surface of the pushing shaft sealing ring seat and the pushing shaft bushing.

Furthermore, a first stepped groove is formed in the front end of the hollow shaft, a second stepped groove is connected behind the first stepped groove, a third stepped groove is connected behind the second stepped groove, and the material pushing shaft seal ring seat is clamped through the groove wall of the first stepped groove and fixed through long bolts matched with screw holes in the groove wall of the second stepped groove; and an outer lining is arranged on the third step groove.

Furthermore, a fifth sealing ring is arranged on the joint surface of the material pushing shaft sealing ring seat and the first stepped groove, and a combined sealing ring is arranged on the joint surface of the long bolt and the material pushing shaft sealing ring seat.

Furthermore, the first oil passing hole is formed in the second stepped groove, the water outlet hole is formed in the first stepped groove, and the pushing shaft sealing ring seat is located between the first oil passing hole and the water outlet hole.

Furthermore, the shell is combined with the wallboard through the mounting platform on one side and connected through a bolt, and a first sealing ring is arranged on the combining surface of the mounting platform and the wallboard.

The invention has the beneficial effects that:

according to the invention, the hollow shaft sealing assembly is arranged at the front end of the hollow shaft to prevent filtrate from entering the bearing seat and prevent the first oil passing hole from entering the material pushing shaft. The method comprises the following steps that a wall plate labyrinth ring and a hollow shaft labyrinth ring are arranged in a separating mode to form two seals, wherein the wall plate labyrinth ring is connected to a wall plate, and the hollow shaft labyrinth ring is connected to a bearing seat so as to separate the wall plate labyrinth ring and the hollow shaft labyrinth ring; meanwhile, high-speed oil seals are arranged on the opposite sides of the wall plate labyrinth ring and the hollow shaft labyrinth ring to enhance the sealing effect and prevent the wall plate labyrinth ring and the hollow shaft labyrinth ring from influencing each other; particularly, the wall board labyrinth ring is connected to the wall board through a bolt, a second sealing ring is arranged on a joint surface of the wall board labyrinth ring and the wall board labyrinth ring, the hollow shaft labyrinth ring is connected to the bearing seat through a bolt, and a third sealing ring is arranged on a joint surface of the hollow shaft labyrinth ring and the bearing seat, so that each installation joint surface of the wall board labyrinth ring and the hollow shaft labyrinth ring is perfectly sealed, and the tight sealing performance of the wall board labyrinth ring and the hollow shaft labyrinth ring is ensured.

The front end of the pushing shaft is provided with the pushing shaft sealing assembly to prevent filtrate from entering the pushing shaft from the bottom of the secondary rotary drum, and simultaneously prevent lubricating oil from entering the rotary drum to pollute the filtrate. Specifically, a sealing ring frame is arranged at the bottom of the secondary rotary drum, and the sealing ring frame is matched with a Glare ring to carry out first sealing; the front end of the hollow shaft is provided with a three-stage stepped groove, a material pushing shaft sealing ring seat arranged on the first-stage stepped groove is matched with a Y-shaped sealing ring and a fifth sealing ring to play a second sealing role, and a water outlet hole formed in the first stepped groove can discharge filtrate in time, so that the multiple safety function is played; in addition, because the pusher shaft seal ring seat is arranged at the first stepped groove through the long bolt, the combined seal ring is arranged at the joint surface of the long bolt and the pusher shaft seal ring seat, and the mounting hole of the long bolt is tightly sealed, so that each possible channel is ensured to be provided with tight sealing measures.

According to the invention, the first oil passing hole and the water outlet hole on the hollow shaft are separated by the pushing shaft sealing ring seat, so that the problem that oil in a cavity between the pushing shaft and the hollow shaft cannot be communicated with filtrate of the rotary drum part is solved, and the oil path and the filtrate passage are strictly separated by matching with the wall plate labyrinth ring and the hollow shaft labyrinth ring, so that the possibility of oil leakage is greatly reduced.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

FIG. 2 is a schematic enlarged view of the invention at section I.

FIG. 3 is an enlarged view of the invention at point II.

Fig. 4 is a schematic structural view of the hollow shaft of the present invention at the multi-step stepped groove.

Fig. 5 is a schematic view of the connection of the housing of the present invention to a wall panel.

The text labels in the figures are represented as: 1. a bearing seat; 2. a support; 3. a wallboard; 4. a casing water inlet device; 5. a secondary drum; 6. a first-stage rotary drum; 7. a first oil passing hole; 8. an oil inlet; 9. a housing; 10. a feed pipe; 11. a second oil passing hole; 12. a first seal ring; 13. a wallboard labyrinth ring; 14. a second seal ring; 15. high-speed oil sealing; 16. a hollow shaft; 17. an oil seal gland; 18. a hollow shaft labyrinth ring; 19. a third seal ring; 20. a Glare circle; 21. a seal ring frame; 22. a fourth seal ring; 23. a Y-shaped seal ring; 24. a pusher shaft seal ring seat; 25. a combined sealing ring; 26. a fifth seal ring; 27. a hollow bushing; 28. a pusher bushing; 29. a sixth seal ring; 30. a material pushing shaft; 31. an outer liner; 32. a second stepped groove; 33. a first step groove; 34. a water outlet hole; 35. an oil outlet hole; 36. a third step groove; 37. a long bolt; 38. and (7) mounting the platform.

Detailed Description

The invention is further illustrated by the following examples.

A closed explosion-proof piston pusher centrifuge comprises a centrifuge body, wherein the front end of the centrifuge body is provided with a shell 9, the shell 9 is provided with a casing water inlet device 4, a rotary drum part is arranged in the shell 9, and the rotary drum part comprises a primary rotary drum 6 and a secondary rotary drum 5, and is characterized in that the centrifuge body comprises a bearing seat 1, the bearing seat 1 is connected with a wallboard 3, the shell 9 is connected to the other side of the wallboard 3, a hollow shaft 16 is arranged in the bearing seat 1, a hollow shaft sealing assembly is arranged on the outer wall of one end of the hollow shaft 16, and the hollow shaft sealing assembly comprises a wallboard labyrinth ring 13 and a hollow shaft labyrinth ring 18; the material pushing device is characterized in that a material pushing shaft 30 is arranged in the hollow shaft 16, a material pushing shaft sealing assembly is arranged on the outer wall of one end of the material pushing shaft 30 and comprises a sealing ring frame 21 and a material pushing shaft sealing ring seat 24, an oil inlet 8 is formed in the upper portion of the bearing seat 1, the oil inlet 8 is communicated with a cavity between the bearing seat 1 and the hollow shaft 16, an oil outlet hole 35 is formed in the bottom of the bearing seat 1, a first oil passing hole 7 is formed in one end of the side wall of the hollow shaft 16, and a second oil passing hole 11 and a water outlet hole 34 are formed in the other end of the side wall of the hollow shaft 16.

Preferably, as shown in fig. 1 and fig. 2, the labyrinth ring 13 of the wall plate is connected to the wall plate 3 through a bolt, and a joint surface of the wall plate and the wall plate is provided with a second sealing ring 14, and the labyrinth ring 13 of the wall plate is tightly attached to the outer wall of the hollow shaft 16 for sealing; the hollow shaft labyrinth ring 18 is connected to the bearing seat 1 through a bolt, a third sealing ring 19 and a sixth sealing ring 29 are arranged on the joint surface of the hollow shaft labyrinth ring 18 and the bearing seat 1, and the hollow shaft labyrinth ring 18 is tightly attached to the outer wall of the hollow shaft 16 for sealing; the hollow shaft labyrinth ring 18 and the wall plate labyrinth ring 13 are arranged at intervals. Because the hollow shaft labyrinth ring 18 and the wallboard labyrinth ring 13 are arranged at intervals, two main sealing measures are formed, and meanwhile, the mounting joint surfaces of the hollow shaft labyrinth ring 18 and the wallboard labyrinth ring 13 are respectively sealed through the third sealing ring 19, the sixth sealing ring 29 and the second sealing ring 14, so that the sealing performance of the mounting surfaces of the hollow shaft labyrinth ring 18 and the wallboard labyrinth ring 13 is ensured.

Preferably, as shown in fig. 1, fig. 2 and fig. 3, a hollow shaft bushing 27 is sleeved on an outer wall of the hollow shaft 16, a plurality of protrusions are arranged on an outer surface of the hollow shaft bushing 27 and are in a zigzag shape, and the hollow shaft labyrinth ring 18 and the wall plate labyrinth ring 13 are closely matched with the outer surface of the hollow shaft bushing 27 for sealing.

Preferably, as shown in fig. 2, the high-speed oil seals 15 are disposed on the opposite sides of the hollow shaft labyrinth ring 18 and the wall plate labyrinth ring 13, the high-speed oil seals 15 are respectively limited by oil seal pressing covers 17, and the oil seal pressing covers 17 are connected to the side surfaces of the hollow shaft labyrinth ring 18 or the wall plate labyrinth ring 13 through bolts. The high-speed oil seal 15 also seals in cooperation with the protrusions on the outer surface of the hollow bush 27, and can play a role in enhancing the sealing effect.

Preferably, as shown in fig. 1 and fig. 3, the seal ring frame 21 is connected to the bottom plate of the secondary drum 5 through bolts, and the thrust shaft seal ring seat 24 is connected to the hollow shaft 16 through a long bolt 37; the outer wall of the front end of the pushing shaft 30 is provided with a pushing shaft bushing 28, and the seal ring frame 21 and the pushing shaft seal ring seat 24 are closely matched with the outer surface of the pushing shaft bushing 28 for sealing.

Preferably, as shown in fig. 3, a greige ring 20 is arranged at a joint sealing surface of the seal ring frame 21 and the pushing bush 28, and a fourth seal ring 22 is arranged at a joint surface of the seal ring frame 21 and a bottom plate of the secondary drum 5; and a Y-shaped sealing ring 23 is arranged at the joint sealing surface of the pushing shaft sealing ring seat 24 and the pushing shaft bushing 28. The seal ring frame 21 and the material pushing shaft seal ring seat 24 also play a role of two main seals, and the Glare ring 20 and the Y-shaped seal ring 23 are arranged in a double mode, so that the joint surface of the seal ring frame 21 and the material pushing shaft seal ring seat 24 is sealed strongly.

Preferably, as shown in fig. 4, a first stepped groove 33 is formed in the front end of the hollow shaft 16, the second stepped groove 32 is connected to the rear end of the first stepped groove 33, the third stepped groove 36 is connected to the rear end of the second stepped groove 32, and the pusher shaft seal ring seat 24 is clamped by the groove wall of the first stepped groove 33 and fixed by a long bolt 37 matching with a screw hole in the groove wall of the second stepped groove 32; the third step groove 36 is provided with an outer liner 31.

Preferably, referring to fig. 3, a fifth sealing ring 26 is disposed at a joint surface of the pusher shaft sealing ring seat 24 and the first stepped groove 33, and a combined sealing ring 25 is disposed at a joint surface of the long bolt 37 and the pusher shaft sealing ring seat 24. Gaps existing in all aspects of the whole installation and the internal through hole of the material pushing shaft sealing ring seat 24 are blocked through the fifth sealing ring 26 and the combined sealing ring 25, and the channels of the gaps are blocked, so that complete sealing is formed.

Preferably, as shown in fig. 4, the first oil passing hole 7 is opened in the second stepped groove 32, the water outlet hole 34 is located in the first stepped groove 33, and the pushing shaft seal ring seat 24 is located between the first oil passing hole 7 and the water outlet hole 34. The material pushing shaft seal ring seat 24 has the function of separating the first oil passing hole 7 and the water outlet hole 34, and separates an oil path and a filtrate path to prevent oil and filtrate from communicating with each other.

Preferably, referring to fig. 5, the outer shell 9 is combined with the wall plate 3 through a mounting platform 38 on one side and connected through a bolt, and a first sealing ring 12 is arranged at the combining surface of the mounting platform 38 and the wall plate 3.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The principles and embodiments of the present invention are explained herein, and the above description of the embodiments is only used to help understand the method and its core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A closed explosion-proof piston pusher centrifuge comprises a centrifuge body, wherein a shell (9) is arranged at the front end of the centrifuge body, a casing water inlet device (4) is arranged on the shell (9), a rotary drum part is arranged in the shell (9), and comprises a first-stage rotary drum (6) and a second-stage rotary drum (5), and is characterized in that the centrifuge body comprises a bearing seat (1), the bearing seat (1) is connected with a wallboard (3), the shell (9) is connected to the other side of the wallboard (3), a hollow shaft (16) is arranged in the bearing seat (1), a hollow shaft sealing assembly is arranged on the outer wall of one end of the hollow shaft (16), and the hollow shaft sealing assembly comprises a wallboard labyrinth ring (13) and a hollow shaft labyrinth ring (18); the material pushing device is characterized in that a material pushing shaft (30) is arranged in the hollow shaft (16), a material pushing shaft sealing assembly is arranged on the outer wall of one end of the material pushing shaft (30), the material pushing shaft sealing assembly comprises a sealing ring frame (21) and a material pushing shaft sealing ring seat (24), an oil inlet (8) is formed in the upper portion of the bearing seat (1), the oil inlet (8) is communicated with a cavity between the bearing seat (1) and the hollow shaft (16), an oil outlet hole (35) is formed in the bottom of the bearing seat (1), a first oil passing hole (7) is formed in one end of the side wall of the hollow shaft (16), and a second oil passing hole (11) and a water outlet hole (34) are formed in the other end of the side wall of the hollow shaft (16).

2. The hermetic explosion-proof piston pusher centrifuge as claimed in claim 1, wherein the said wall plate labyrinth ring (13) is connected to the wall plate (3) through bolts and the joint surface of the two is provided with the second seal ring (14), the wall plate labyrinth ring (13) seals against the outer wall of the hollow shaft (16); the hollow shaft labyrinth ring (18) is connected to the bearing seat (1) through a bolt, a third sealing ring (19) and a sixth sealing ring (29) are arranged on the joint surface of the bearing seat and the bearing seat, and the hollow shaft labyrinth ring (18) is tightly attached to the outer wall of the hollow shaft (16) for sealing; the hollow shaft labyrinth ring (18) and the wallboard labyrinth ring (13) are arranged at intervals.

3. The sealed explosion-proof piston pusher centrifuge as claimed in claim 2, wherein the hollow shaft (16) is sleeved with a hollow bushing (27) on the outer wall, the outer surface of the hollow bushing (27) is provided with a plurality of protrusions in a zigzag shape, and the hollow shaft labyrinth ring (18) and the wall plate labyrinth ring (13) are closely matched with the outer surface of the hollow bushing (27) for sealing.

4. A sealed explosion-proof piston pusher centrifuge according to claim 2, characterized in that one side of the hollow shaft labyrinth ring (18) opposite to the wall plate labyrinth ring (13) is provided with a high-speed oil seal (15), the high-speed oil seals (15) are respectively limited by oil seal pressing covers (17), and the oil seal pressing covers (17) are connected to the side of the hollow shaft labyrinth ring (18) or the wall plate labyrinth ring (13) through bolts.

5. A closed explosion-proof piston pusher centrifuge as defined in claim 1, characterized in that the seal ring holder (21) is bolted to the bottom plate of the secondary drum (5), and the pusher shaft seal ring seat (24) is connected to the hollow shaft (16) by means of long bolts (37); the outer wall of the front end of the pushing shaft (30) is provided with a pushing shaft bushing (28), and the sealing ring frame (21) and the pushing shaft sealing ring seat (24) are closely matched with the outer surface of the pushing shaft bushing (28) for sealing.

6. A closed explosion-proof piston pusher centrifuge as defined in claim 5, characterized in that the seal ring holder (21) is provided with a Gray ring (20) at the joint sealing surface with the pusher bushing (28), and the seal ring holder (21) is provided with a fourth seal ring (22) at the joint surface with the bottom plate of the secondary drum (5); and a Y-shaped sealing ring (23) is arranged at the joint sealing surface of the pushing shaft sealing ring seat (24) and the pushing shaft bushing (28).

7. A sealed explosion-proof piston pusher centrifuge as defined in claim 5, characterized in that the hollow shaft (16) is provided with a first stepped groove (33) at the front end, the first stepped groove (33) is followed by a second stepped groove (32), the second stepped groove (32) is followed by a third stepped groove (36), the pusher shaft seal ring seat (24) is locked by the groove wall of the first stepped groove (33) and fixed by a long bolt (37) matching with a screw hole on the groove wall of the second stepped groove (32); an outer lining (31) is arranged on the third step groove (36).

8. A closed explosion-proof piston pusher centrifuge as defined in claim 7, characterized in that the fifth sealing ring (26) is arranged at the joint surface of the pusher shaft sealing ring seat (24) and the first stepped groove (33), and the combined sealing ring (25) is arranged at the joint surface of the long bolt (37) and the pusher shaft sealing ring seat (24).

9. The hermetic explosion-proof piston pusher centrifuge as recited in claim 7, wherein the first oil passing hole (7) is opened at the second stepped groove (32), the water outlet hole (34) is located at the first stepped groove (33), and the pusher shaft seal ring seat (24) is located between the first oil passing hole (7) and the water outlet hole (34).

10. A closed explosion-proof piston pusher centrifuge as defined in claim 9, characterized in that the casing (9) is joined to the wall plate (3) by means of a mounting platform (38) on one side and connected by means of bolts, and the first sealing ring (12) is arranged on the joint surface of the mounting platform (38) and the wall plate (3).