CN211975886U - A zero-leakage combined shaft seal device for high temperature and high dust conditions - Google Patents

Abstract

The utility model relates to the technical field of shaft seal, in particular to a zero-leakage combined shaft seal device for high-temperature and high-dust working conditions, wherein a fixed end combined seal device is sleeved on a drive end on the left side of a rotating shaft, a sliding end combined seal device is arranged on the other end on the right side of the rotating shaft and is symmetrically arranged relative to a pyrolysis reactor of the fixed end combined seal device; when the sliding end limiting mechanism rotates along with the rotating shaft, the sliding end double-end-face mechanical seal rotates synchronously with the sliding end limiting mechanism through the smooth guide rod. The utility model discloses can realize under 500 ℃ -1200 ℃ ambient temperature, the span of axles is 10 ~ 15 meters long, and the diameter is the reliable and stable operation of shaft seal when more than 400mm, guarantees the zero leakage of solid heat carrier particle dust and toxic gas in the pyrolytic reaction ware.

Description

A zero-leakage combined shaft seal device for high temperature and high dust conditions

technical field

The utility model belongs to the technical field of shaft seals, in particular to a zero-leakage combined shaft seal device used in high temperature and high dust conditions.

Background technique

The pyrolysis reactor is the key core equipment in the domestic waste pyrolysis system, which plays the role of conveying, mixing and stirring domestic waste and solid heat carrier. Under the action of the high temperature heat carrier, the domestic waste is decomposed into CO, H ₂ S, H ₂ and other flammable and explosive toxic pyrolysis gases, because the whole system is in a high-temperature aerobic environment of about 500-1200 ℃ and the solid heat carrier is fine particles, the long axis span of the pyrolysis reactor is long. , it will cause jumping during operation, there is a certain gas leakage, the pyrolysis gas overflowing the reactor will pollute the surrounding environment and form an explosive gas environment, and the air entering the pyrolysis reactor will cause combustion, so the pyrolysis reaction The performance requirements of the device on the shaft seal are zero leakage and the environmental conditions of the shaft seal are harsh. The shaft seals commonly used at home and abroad for high temperature are mainly packing seals and mechanical seals.

The packing sealing structure is simple, and the machining accuracy of the shaft is low, but the packing sealing performance is poor, the packing gland needs to be tightened frequently during use, the stability is poor, and it cannot be completely sealed. The explosive toxic pyrolysis gas leaks out, and the power consumption is too large, so it is not suitable as a sealing device for the rotating shaft of the pyrolysis reactor.

Although the mechanical seal has good sealing performance and high stability, the simple mechanical seal is directly exposed in the pyrolysis reactor and directly seals the high-temperature solid heat carrier. After the mechanical seal is damaged, the water used to cool the mechanical seal easily enters the pyrolysis reactor, which will greatly affect the pyrolysis process. In addition, in a high temperature environment, the long shaft is prone to expansion and radial runout, which will cause extrusion and imbalance between the dynamic and static rings of the traditional mechanical seal, resulting in damage to the mechanical seal. Therefore, the traditional mechanical seal cannot be used as a pyrolysis solution. Reactor seals.

Therefore, a new sealing device is urgently needed to meet the sealing requirements of the shaft of the pyrolysis reactor.

SUMMARY OF THE INVENTION

The purpose of the utility model is to provide a zero-leakage combined shaft sealing device for high-temperature and high-dust working conditions, which has good sealing performance and high stability in a high-temperature environment.

The technical scheme of the present utility model is as follows:

A zero-leakage combined shaft sealing device for high temperature and high dust conditions, used to seal the gap Q between the dual rotating shafts of a pyrolysis reactor and the shell of the pyrolysis reactor, to prevent harmful gases from escaping; including a fixed end combination Sealing device and sliding end combined sealing device;

The fixed-end combined sealing device is sleeved on the drive end on the left side of the rotating shaft, and includes a fixed-end isolation gas seal, a fixed-end multi-stage labyrinth seal, a fixed-end brush seal, a fixed-end double-end mechanical seal and a fixed-end limiter. mechanism;

The sliding end combined sealing device is located at the other end of the right side of the rotating shaft, and is symmetrically arranged with the fixed end combined sealing device relative to the pyrolysis reactor, including the sliding end isolation gas seal, the sliding end multi-stage labyrinth seal, the sliding end brush type Seal, double mechanical seal on sliding end and limit mechanism on sliding end.

The sliding end isolation air seal and the fixed end isolation air seal have the same structure, the sliding end multi-stage labyrinth seal and the fixed end multi-stage labyrinth seal have the same structure, and the sliding end brush seal and the fixed end brush seal have the same structure. The structure of the double-end mechanical seal at the sliding end is the same as that of the double-end mechanical seal at the fixed end, and the structure of the limiting mechanism at the fixed end and the limiting mechanism at the sliding end are different.

The fixed end isolation gas seal is the first seal in contact between the fixed end combined sealing device and the shell of the pyrolysis reactor; the fixed end isolation gas seal is in the shape of a circular ring and is sleeved on the rotating shaft; The air supply channel is processed on the ring, the air inlet of the air supply channel is located on the side of the outer ring of the ring, and the air outlet is located on the end face of one side of the ring; the fixed end isolates the air-sealed air inlet and the isolation air The supply end is connected, the air outlet is facing the gap Q, and is connected to the isolation gas supply end and the gap Q; the isolation gas is an inert gas that does not react with the sealing medium, and the pressure of the isolation gas is higher than the internal pressure of the pyrolysis reactor by no more than 10kpa.

The fixed end multi-stage labyrinth seal is processed on the inner ring side wall of the annular cavity which is isolated from the air seal at the fixed end, and is in contact with the rotating shaft to form a second seal; the fixed end multi-stage labyrinth seal has a total of 4- 5 throttle backlashes; the spacing between each throttle backlash is 1mm, and the clearance between each throttle backlash and the shaft is 0.5mm.

The fixed end brush seal is composed of an annular brush, which is located on the left side of the fixed end isolation air seal, and is connected with the fixed end isolation air seal through bolts to form a third seal; Coated with high-temperature-resistant grease, the rotating shaft will not be scratched during long-term operation, and at the same time, it can compensate for the gap caused by the beating of the rotating shaft. The thickness of the annular brush is 5mm.

The fixed-end double-end mechanical seal is located on the left side of the fixed-end brush seal, and the two are connected by bolts; the fixed-end double-end mechanical seal includes a cooling water cavity, a balance tank, and two sides of the cooling water cavity. There are two sets of moving rings and static rings; the one on the right side of the cooling water chamber is set as moving ring A and static ring A, and the one on the left side of the cooling water chamber is set as moving ring B and static ring B; The static ring A adopts the double hard surface sealing design of cemented carbide material; the dynamic ring B adopts the cemented carbide, and the static ring B adopts the graphite material for the sealing design of the combination of soft and hard surfaces. At the same time, the moving ring B is connected to the moving ring seat of the fixed end double-end mechanical seal through bolts; the balance tank is connected to the cooling water cavity through a hose, and is placed outside the combined sealing device as a water storage tank. Bit alarm device.

The fixed-end limiting mechanism is an annular structure, located on the left side of the fixed-end double-end mechanical seal, sleeved on the rotating shaft and fastened in the radial direction by tightening screws, and at the same time with the fixed-end double-end mechanical seal moving ring. The left side of the seat is held together by screws.

The sliding end limiting mechanism is an annular structure, located on the right side of the double-end mechanical seal at the sliding end, and is fastened on the rotating shaft in the radial direction by tightening screws; on the upper edge of the outer ring of the sliding end limiting mechanism Axially machined grooves are used to limit the smooth guide rod.

One end of the smooth guide rod and the right side of the double-end mechanical seal movable ring seat of the sliding end are fixed by threads, and the middle part of the smooth guide rod is clamped in the groove on the limit mechanism of the sliding end.

When the sliding end limiting mechanism rotates together with the rotating shaft, the sliding end double-end mechanical seal rotates synchronously with the sliding end limiting mechanism through the smooth guide rod.

The beneficial effects of the present utility model are:

(1) The isolation gas seal and the multi-stage labyrinth seal of the present utility model can ensure that a large amount of high-temperature gas dust will not enter the sealing system behind, and the brush seal can adapt to the runout of the rotating shaft to a certain extent, ensuring that the solid dust particles will not Enter into the back double mechanical seal, which can ensure zero leakage of pyrolysis gas.

(2) The auxiliary system of the utility model includes a balance tank and an alarm device to ensure that the cooling water in the double-end mechanical seal will not enter the equipment after the device is damaged, affecting the overall operation of the equipment.

(3) The combined sealing device of the present invention is divided into two forms: fixed end and sliding end. By making different structural designs on the limit mechanism, the thermal expansion of the rotating shaft can be moved to the sliding end direction, so that the combined sealing device Stable work under the condition of thermal expansion shaft extension.

(4) The utility model adopts the combined sealing device including isolation gas seal, multi-stage labyrinth seal, brush seal, double-end face seal, limit mechanism and auxiliary system, which can realize the axial The span is 10 to 15 meters long, and the shaft seal runs stably and reliably when the diameter is over 400 mm, ensuring zero leakage of solid heat carrier particles, dust and toxic gases in the pyrolysis reactor.

Description of drawings

Fig. 1 is the structural schematic diagram of the upper half of the combined sealing device of the present invention;

Figure 2 is a schematic diagram of a fixed end limiting mechanism;

FIG. 3 is a schematic diagram of a sliding end limiting mechanism.

In the figure: 1 fixed end combined sealing device; 2 sliding end combined sealing device; 11 fixed end isolation gas seal; 12 fixed end multi-stage labyrinth seal; 13 fixed end brush seal; 14 fixed end double mechanical seal; 141 fixed end Double mechanical seal moving ring seat; 15 fixed end limit mechanism; 21 sliding end isolation gas seal; 22 sliding end multi-stage labyrinth seal; 23 sliding end brush seal; 24 sliding end double end mechanical seal; 241 sliding end double end face Mechanical seal moving ring seat; 25 Sliding end limit mechanism; 251 Sliding end limit mechanism before shaft expansion; 252 Sliding end limit mechanism after shaft expansion; 26 Smooth guide rod.

Detailed ways

The present utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, a zero leakage combined shaft seal device for high temperature and high dust conditions includes a fixed end combined seal device 1 and a sliding end combined seal device 2. In the pyrolysis reactor, there are two rotating shafts that can transport and mix solid heat carrier and domestic waste. The combined sealing device of the utility model is used to seal the gap Q between the double rotating shafts and the shell of the pyrolysis reactor to prevent harmful gases. escape.

The fixed-end combined sealing device 1 is sleeved on the drive end on the left side of the rotating shaft, and includes a fixed-end isolation gas seal 11 , a fixed-end multi-stage labyrinth seal 12 , a fixed-end brush seal 13 , and a fixed-end double-end mechanical seal 14 . And the fixed end limiting mechanism 15 .

The fixed end isolation gas seal 11 is the first seal in contact between the fixed end combined sealing device 1 and the outer shell of the pyrolysis reactor. The fixed end isolation air seal 11 is in the shape of a circular ring and is sleeved on the rotating shaft. An air supply channel is processed on the circular ring, the air inlet of the air supply channel is located on the side surface of the outer ring of the circular ring, and the air outlet is located on one end face of the circular ring. The air inlet of the isolation gas seal 11 at the fixed end communicates with the isolation gas supply end, and the air outlet faces the gap Q and communicates with the isolation gas supply end and the gap Q. By introducing the isolation gas into the gas supply channel of the isolation gas seal 11 at the fixed end, a positive pressure is formed in the gap Q, and the high-temperature solid heat carrier that escapes from the pyrolysis reactor to the gap Q is blown out, and the pyrolysis is also prevented. The high-temperature gas of the reactor enters the interior of the fixed-end combined sealing device 1 and destroys the combined sealing device to form a good seal. The isolation gas is any one of N2, CO2, and water vapor, and the pressure of the isolation gas is higher than the internal pressure of the pyrolysis reactor by no more than 10 kPa.

The fixed end multi-stage labyrinth seal 12 is processed on the inner ring side wall of the annular cavity of the fixed end isolation gas seal 11 and is in contact with the rotating shaft. The fixed end multi-stage labyrinth seal 12 has 4-5 throttle backlashes, the spacing between each throttle backlash is 1mm, and the gap between each throttle backlash and the shaft is 0.5mm. Due to the turbulent mixing effect of the airflow, when the pyrolysis gas mixed with the solid heat carrier passes through the fixed end labyrinth seal 12, a part of the kinetic energy will be converted into heat energy, and the kinetic energy will be reduced, so as to achieve the purpose of sealing and form a second seal.

The fixed end brush seal 13 is composed of an annular brush with a thickness of 5 mm, is located on the left side of the fixed end isolation air seal 11, and is connected to the fixed end isolation air seal 11 through bolts. The brush wire of the fixed end brush seal 13 adopts nano-level technology, and the brush wire is coated with high temperature resistant lubricating grease, which will not cause scratches on the rotating shaft after long-term operation, and can compensate for the gap generated by the beating of the rotating shaft. A third seal is formed.

The fixed-end double-end mechanical seal 14 is located on the left side of the fixed-end brush seal 13, and the two are connected by bolts. The fixed-end double-end mechanical seal 14 includes a cooling water cavity, a balance tank, and two sets of moving rings and static rings arranged on both sides of the cooling water cavity. The cooling water cavity is sleeved on the rotating shaft, and the group on the right side of the cooling water cavity is set as the moving ring A and the static ring A, both of which are designed with a double hard surface seal made of cemented carbide; the left side of the cooling water cavity is designed One group is set as moving ring B and static ring B, the moving ring B is made of cemented carbide, and the static ring B is made of graphite material, so that the combination of soft and hard sealing structure can ensure the fixed end double-end mechanical seal 14 in the high temperature solid heat carrier. It can run stably in the environment. The moving ring B is connected to the moving ring seat 141 of the fixed end double-end mechanical seal through bolts.

By feeding circulating cooling water into the cooling water cavity, it is ensured that the temperature inside the fixed-end double-end mechanical seal 14 will not be too high, and the O-ring inside the fixed-end double-end mechanical seal 14 is prevented from being damaged by high temperature, so that the It can also operate stably and safely in high temperature environments. The balance tank is connected with the cooling water cavity through a hose, and is placed outside the combined sealing device as a water storage tank. At the same time, a liquid level alarm device is provided on the water outlet tank. Once the cooling water leaks, it will enter the balance tank. When the liquid level reaches the warning line, the system will alarm, which can prevent the cooling water from leaking into the pyrolysis reactor shell and through the fixed end brush seal 13 and the fixed end multi-stage labyrinth seal 12. The gap Q formed between the combined sealing devices 1 is fixed, thereby preventing cooling water from entering the pyrolysis reactor.

As shown in FIG. 2, the fixed end limiting mechanism 15 is an annular structure, located on the left side of the fixed end double-end mechanical seal 14, sleeved on the rotating shaft and fastened radially by tightening screws, and at the same time The left side of the fixed-end double-end mechanical seal movable ring seat 141 is fixed together by screws, which can not only ensure the synchronous rotation of the rotating shaft and the fixed-end combined sealing device 1, but also ensure that the driving end on the left side of the rotating shaft is heated and expanded, and the amount of expansion The direction of the shaft can be conducted to the other end of the right side of the rotating shaft, so that the fixed end combined sealing device 1 will not be affected by thermal stress.

The sliding end combined sealing device 2 is arranged on the other end of the right side of the rotating shaft, and is symmetrically arranged with the fixed end combined sealing device 1 relative to the pyrolysis reactor, including the sliding end isolation gas seal 21, the sliding end multi-stage labyrinth seal 22, The sliding end brush seal 23 , the sliding end double-end mechanical seal 24 and the sliding end limiting mechanism 25 .

The sliding end isolation air seal 21 and the fixed end isolation air seal 11 have the same structure, the sliding end multi-stage labyrinth seal 22 and the fixed end multi-stage labyrinth seal 12 have the same structure, the sliding end brush seal 23 and the fixed end brush type The structure of the seal 13 is the same, and the structure of the double-end mechanical seal 24 at the sliding end is the same as that of the double-end mechanical seal 14 at the fixed end.

The sliding end limiting mechanism 25 is an annular structure, located on the right side of the sliding end double-end mechanical seal 24, and is fastened on the rotating shaft in the radial direction by tightening screws. A groove is axially processed on the outer ring of the sliding end limiting mechanism 25 for limiting the smooth guide rod 26 .

One end of the smooth guide rod 26 and the right side of the sliding end double-end mechanical seal ring seat 241 are fixed by threads. When the sliding end limiting mechanism 25 rotates together with the rotating shaft, the sliding end double-end mechanical seal 24 rotates synchronously with the sliding end limiting mechanism 25 through the smooth guide rod 26 . As shown in FIG. 3 , after the rotating shaft is thermally expanded, the sliding end double-end mechanical seal 24 and the sliding end limiting mechanism 25 axially slide relative to each other through the smooth guide rod 26 to offset the influence of the rotating shaft under high temperature.

Claims (10)

1. a zero-leakage combined shaft seal device for high temperature and high dust conditions, characterized in that: the gap Q between the dual rotating shafts for sealing the pyrolysis reactor and the shell of the pyrolysis reactor prevents harmful gases from escaping out; including the fixed end combined sealing device (1) and the sliding end combined sealing device (2); The fixed end combined sealing device (1) is sleeved on the drive end on the left side of the rotating shaft, and includes a fixed end isolation gas seal (11), a fixed end multi-stage labyrinth seal (12), and a fixed end brush seal (13) , fixed end double-end mechanical seal (14) and fixed end limit mechanism (15); The sliding end combined sealing device (2) is arranged at the other end of the right side of the rotating shaft, and is symmetrically arranged with the fixed end combined sealing device (1) relative to the pyrolysis reactor, and comprises a sliding end isolation gas seal (21), a sliding end sealing device (1), and a sliding end sealing device (1). A multi-stage labyrinth seal (22), a sliding end brush seal (23), a sliding end double-end mechanical seal (24) and a sliding end limiting mechanism (25). 2. A zero-leakage combined shaft seal device for high temperature and high dust conditions as claimed in claim 1, characterized in that: the sliding end isolation gas seal (21) and the fixed end isolation gas seal (11) The structure of the sliding end multi-stage labyrinth seal (22) and the fixed end multi-stage labyrinth seal (12) are the same, and the sliding end brush seal (23) and the fixed end brush seal (13) have the same structure, the sliding end The double-end mechanical seal (24) has the same structure as the fixed-end double-end mechanical seal (14), and the fixed-end limiting mechanism (15) and the sliding-end limiting mechanism (25) have different structures. 3. A zero-leakage combined shaft seal device for high temperature and high dust conditions as claimed in claim 1, characterized in that: the fixed end isolation gas seal (11) is a fixed end combined seal device (1) The first seal in contact with the shell of the pyrolysis reactor; the fixed end isolation gas seal (11) is in the shape of a circular ring and is sleeved on the rotating shaft; an air supply channel is processed on the circular ring to supply air The air inlet of the channel is located on the side surface of the outer ring of the ring, and the air outlet is located on the end face of one side of the ring; the air inlet of the isolation gas seal (11) of the fixed end is communicated with the isolation gas supply end, and the air outlet is facing The gap Q is connected to the isolation gas supply end and the gap Q; the isolation gas is an inert gas that does not react with the sealing medium, and the isolation gas pressure is higher than the internal pressure of the pyrolysis reactor by no more than 10kpa. 4. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to claim 1, characterized in that: the fixed end multi-stage labyrinth seal (12) is processed on the fixed end isolation gas seal ( 11) The inner ring side wall of the annular cavity is in contact with the rotating shaft to form a second seal; the fixed end multi-stage labyrinth seal (12) has a total of 4 to 5 throttling tooth gaps; each throttling The backlash spacing is 1mm, and the clearance between each throttle backlash and the shaft is 0.5mm. 5. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to claim 1, characterized in that: the fixed end brush seal (13) is composed of an annular brush, which is isolated at the fixed end The left side of the air seal (11) is connected to the fixed end isolation air seal (11) by bolts to form a third seal; the brush wire adopts nano-level technology, and the brush wire is coated with high temperature resistant lubricating grease, which can run for a long time. There will be no scratches on the rotating shaft, and at the same time, it can compensate for the gap caused by the beating of the rotating shaft. The thickness of the annular brush is 5mm. 6. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to claim 1, characterized in that: the fixed end double-end mechanical seal (14) is located at the fixed end brush seal (13) ), the two are connected by bolts; the fixed end double-end mechanical seal (14) includes a cooling water cavity, a balance tank, and two sets of moving rings and static rings arranged on both sides of the cooling water cavity; wherein the cooling The group on the right side of the water chamber is set as the moving ring A and the static ring A, and the group on the left side of the cooling water chamber is set as the moving ring B and the static ring B; both the moving ring A and the static ring A are made of cemented carbide. Double hard surface seal design; the moving ring B is made of hard alloy, and the static ring B is made of graphite material as a seal design combining soft and hard surfaces; at the same time, the moving ring B is connected to the fixed end double-end mechanical seal moving ring seat (141) through bolts; The balance tank is connected with the cooling water cavity through a hose, and is placed outside the combined sealing device as a water storage tank. At the same time, the water storage tank is provided with a liquid level alarm device. 7. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to claim 1, characterized in that: the fixed end limiting mechanism (15) is an annular structure, located on the double end faces of the fixed end The left side of the mechanical seal (14) is sleeved on the rotating shaft and fastened radially by tightening screws, and is simultaneously fixed with the left side of the double-end mechanical seal dynamic ring seat (141) at the fixed end by screws. 8. A zero-leakage combined shaft seal device for high temperature and high dust conditions as claimed in claim 1, characterized in that: the sliding end limiting mechanism (25) is an annular structure, located on both end faces of the sliding end The right side of the mechanical seal (24) is fastened on the rotating shaft in the radial direction by tightening screws; grooves are machined in the axial direction on the outer ring of the sliding end limiting mechanism (25) for smooth guide The rod (26) is limited. 9. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to claim 8, characterized in that: one end of the smooth guide rod (26) and the sliding end double-end mechanical seal moving ring seat The right side of (241) is fixed by threads, and the middle part of the smooth guide rod (26) is clamped in the groove on the sliding end limiting mechanism (25). 10. A zero-leakage combined shaft seal device for high temperature and high dust conditions according to any one of claims 1 to 9, characterized in that: when the sliding end limiting mechanism (25) rotates together with the rotating shaft When the sliding end double-end mechanical seal (24) rotates synchronously with the sliding end limiting mechanism (25) through the smooth guide rod (26).

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