An oil and gas seal structure for airflow mill classification and mechanical pulverization classification

Abstract

The utility model relates to a sealing structure technical field of crushing equipment, concretely relates to an oil gas sealing structure for airflow mill grading and mechanical crushing grading, aims at solving the problem that the sealing structure is affected by particle and leads to poor sealing effect. Including spindle and bearing seat, and the bearing piece, oil baffle, elastic baffle, bearing cover and sealing ring that are coaxially assembled with the spindle, still include labyrinth ring, the air passage is opened in the labyrinth ring, and the air inlet pipe is connected on the bearing seat, and the air inlet pipe is communicated with the air passage. The labyrinth ring is assembled in the bearing seat end portion and prevents the particle from entering the sealing structure, and the air passage is opened in the labyrinth ring, and the gas is injected into the air passage, prevents the dust particle from entering the sealing gap, thereby reduces the erosion and pollution of the particle to the bearing piece and sealing structure.

Description

Technical Field

[0001] This utility model relates to the field of sealing structure technology for crushing equipment, specifically to an oil-gas sealing structure for air jet mill classification and mechanical crushing classification. Background Technology

[0002] In air classifiers, pneumatic classifiers, and various mechanical crushing and screening equipment, shaft end seals, bearing housing protection, and lubrication systems have a decisive impact on equipment reliability, product cleanliness, and maintenance costs. Common sealing and protection methods include labyrinth seals, lip seals, end-face mechanical seals, gas purging, oil baths, and oil seal housings. To achieve airtight isolation between the feed inlet and the process airflow, rotary feeders, star feeders, or rotary valves are also commonly used.

[0003] In practical industrial applications, equipment such as air classifiers and classifiers have the following typical characteristics and requirements: the working medium is a mixture of gas and oil mist containing solid particles; dust significantly corrodes bearings and seals, resulting in multiple failure modes and frequent maintenance and downtime; to ensure classification accuracy and reduce cross-contamination, it is often necessary to separate the lubrication points from the powder flow or use oilless lubrication, but in some heavy-load or high-temperature applications, oil lubrication is still required to ensure bearing life; traditional purging methods and labyrinth structures involve a trade-off between efficiency and energy consumption in preventing fine particles or oil mist from penetrating, often accompanied by large compressed air consumption or sacrifice of seal life.

[0004] The main problems with existing technologies are: mechanical seals are easily worn by particulate matter, leading to seal failure and requiring frequent replacement, which increases equipment maintenance costs and downtime; although labyrinth seals can effectively prevent particulate matter from entering, they cannot prevent the leakage of lubricating grease, resulting in insufficient bearing lubrication and shortening the bearing's service life. Utility Model Content

[0005] The technical problem to be solved by this utility model is that the sealing structure in air jet mills or mechanical crushing equipment is easily affected by broken particles, resulting in poor sealing effect. The purpose is to provide an oil-gas sealing structure for air jet mill classification and mechanical crushing classification. By opening air passages on the labyrinth ring and injecting airflow, it can effectively prevent particles or lubricating grease from entering the sealing structure.

[0006] This utility model is achieved through the following technical solution:

[0007] An oil-gas sealing structure for classifying air jet mills and mechanical crushing includes a main shaft and a bearing housing, as well as bearing components, an oil retaining ring, an elastic retaining ring, a bearing cover, and a sealing ring coaxially assembled with the main shaft. It also includes a labyrinth ring with an air passage inside. An air inlet pipe is connected to the bearing housing, and the air inlet pipe and the air passage are connected.

[0008] In the above technical solution, a labyrinth ring is installed at the end of the bearing housing to prevent particles from entering the sealing structure. At the same time, an air passage is opened in the labyrinth ring and gas is injected into the air passage to prevent dust particles from entering the sealing gap, thereby reducing the erosion and contamination of the bearing components and sealing structure by particles.

[0009] Preferably, the labyrinth ring includes an upper sealing cover and a lower sealing cover that interlock. The diameter of the upper sealing cover gradually decreases from the top surface to the bottom surface. A plurality of guide grooves are formed on the outer peripheral wall of the upper sealing cover. A plurality of steps that cooperate with the guide grooves are formed on the inner peripheral wall of the lower sealing cover from the top surface to the bottom surface. An oil passage is formed on the top surface of the lower sealing cover facing downward. A baffle is provided on the top surface of the oil passage facing upward. The air passage is annular and located between the baffle and the inner peripheral wall of the lower sealing cover.

[0010] In the above technical solution, the mechanical fit and flow guiding structure of the upper and lower sealing caps make the sealing area form a more complex blocking path, increasing the resistance of the particles passing through, thereby improving the particle blocking ability and reducing the wear of the sealing end face directly impacted.

[0011] Preferably, the bearing housing is connected to an oil injection pipe, which is connected to an oil passage, and the top edge of the upper sealing cover extends downward toward the partition and engages with the partition.

[0012] In the above technical solution, the oil injection pipe injects lubricating grease into the oil passage, which can ensure that the lubricating oil reaches the bearing point stably. At the same time, the connection between the partition and the upper sealing cover realizes the structural separation of the oil passage and the air passage, reducing the probability that the oil will be carried away by the purging air of the air passage or flow back into the process flow during the oil injection process.

[0013] Preferably, a plurality of guide vanes are arranged in a ring along the axis of the upper sealing cover inside the air passage.

[0014] In the above technical solution, the guide vanes introduce a tangential flow component into the air passage, so that the gas not only flows radially but also forms a tangential force in the circumferential direction, which can effectively deflect or eject particles and oil droplets entering the air passage, thereby improving the interception efficiency of particles.

[0015] Preferably, a plurality of diaphragms are equidistantly arranged around the two side walls of the airway, with adjacent diaphragms on opposite sides contracting toward the airway or expanding outward.

[0016] In the above technical solution, the diaphragm forms a local structure of contraction and expansion within the airway, which causes local acceleration and pressure of the gas, helps to form a shear layer and a separation layer, thereby enhancing the particle deflection and sedimentation capabilities.

[0017] Preferably, a grading wheel is detachably connected to the bottom of the bearing housing, and the fit tolerance between the labyrinth ring and the grading wheel is H7 / g6.

[0018] In the above technical solution, the mechanical coaxiality and radial clearance between the labyrinth ring and the grading wheel are ensured by the tolerance, thereby reducing the sealing wear and leakage caused by eccentricity and radial runout.

[0019] Preferably, the air passage is also connected to an air outlet pipe, and the oil passage is also connected to an oil drain pipe, with the air inlet pipe and air outlet pipe, and the oil injection pipe and oil drain pipe respectively arranged symmetrically.

[0020] In the above technical solution, the air outlet pipe enables the purge air to form a closed flow direction, which can orderly guide the particles and oil mist carried in the air passage to the collection and filtration device. The oil outlet pipe provides a smooth path for return oil and waste oil, and can form a stable return oil cycle in conjunction with the oil injection pipe.

[0021] Preferably, a filter screen is provided at one end of the oil passage near the oil injection pipe, and a filter element is provided at the oil passage near the filter screen.

[0022] In the above technical solution, the filter screen and filter element trap fine dust and tiny solid pollutants, thereby significantly reducing the solid content of the reinjected oil and avoiding secondary pollution and bearing contamination caused by oil return.

[0023] Preferably, the opening depth of the airway is 2mm-5mm, the opening depth of the airway is 1mm-3mm, and the longitudinal cross-sectional shape of the airway is rectangular or trapezoidal.

[0024] The above technical solution can ensure that compressed air forms a stable airflow in the air passage, effectively preventing particulate matter and lubricating grease from entering the sealing gap.

[0025] Preferably, the labyrinth ring is made of wear-resistant alloy steel, and the hardness of the labyrinth ring is 45HRC-50HRC.

[0026] In the above technical solution, the use of high-hardness and wear-resistant materials can significantly improve the durability of labyrinth rings in dusty media, reduce structural wear, thereby extending the seal life and reducing the replacement frequency and maintenance costs.

[0027] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0028] 1. A labyrinth ring is installed between the bearing housing and the grader wheel to effectively reduce the entry of particles into the sealing structure. At the same time, an air passage is opened on the labyrinth ring and gas is injected into the air passage to effectively prevent particles and lubricating grease from entering the sealing gap, avoid wear of mechanical seals, extend equipment maintenance cycle and reduce processing costs.

[0029] 2. By setting up oil injection pipes, oil drain pipes and oil passages, lubricating oil is injected into the oil passages to form a circuit, which can effectively increase the service life of bearings, reduce downtime for maintenance, avoid wear of mechanical seals, extend equipment maintenance cycles and reduce processing costs. Attached Figure Description

[0030] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0031] Figure 1 This is a schematic diagram of the structure of this utility model;

[0032] Figure 2 This is a schematic diagram of the structure of the main shaft and bearing housing in this utility model.

[0033] Figure 3 This is a cross-sectional view of the labyrinth ring during assembly in this utility model;

[0034] Figure 4 This is an exploded view of the maze ring in this utility model.

[0035] The attached diagram shows the markings and corresponding component names:

[0036] 1. Bearing housing; 11. Oil retainer ring; 12. Bearing component; 13. Elastic retaining ring; 14. Bearing cover; 2. Main shaft; 3. Labyrinth ring; 31. Upper sealing cover; 32. Lower sealing cover; 4. Air passage; 41. Inlet pipe; 42. Outlet pipe; 5. Oil passage; 51. Oil injection pipe; 52. Oil discharge pipe; 6. Guide vane; 7. Grader wheel. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are for explaining the utility model only and are not intended to limit the utility model. It should be noted that this utility model is already in the actual research and development stage.

[0038] Example 1

[0039] like Figures 1 to 4 As shown, this embodiment 1 provides an oil-gas sealing structure for air jet milling and mechanical crushing classification, including a main shaft 2 and a bearing housing 1, as well as a bearing component 12, an oil retaining ring 11, an elastic retaining ring 13, a bearing cover 14 and a sealing ring coaxially assembled with the main shaft 2, and also includes a labyrinth ring 3, with an air passage 4 opened in the labyrinth ring 3, and an air inlet pipe 41 connected to the bearing housing 1, the air inlet pipe 41 and the air passage 4 being connected.

[0040] like Figure 3 and Figure 4 As shown, the labyrinth ring 3 includes an upper sealing cover 31 and a lower sealing cover 32 that interlock with each other. The diameter of the upper sealing cover 31 gradually decreases from the top surface to the bottom surface. Several guide grooves are formed on the outer peripheral wall of the upper sealing cover 31. Several steps that cooperate with the guide grooves are formed on the inner peripheral wall of the lower sealing cover 32 from the top surface to the bottom surface. An oil passage 5 is formed on the top surface of the lower sealing cover 32 and a baffle is provided on the top surface of the oil passage 5. The air passage 4 is annular and located between the baffle and the inner peripheral wall of the lower sealing cover 32.

[0041] like Figures 1 to 3 As shown, an oil injection pipe 51 is connected to the bearing housing 1. The oil injection pipe 51 is connected to the oil passage 5. The top edge of the upper sealing cover 31 extends downward toward the partition and is fastened to the partition.

[0042] like Figures 1 to 3 As shown, the air passage 4 is also connected to the air outlet pipe 42, and the oil passage 5 is also connected to the oil drain pipe 52. The air inlet pipe 41 and the air outlet pipe 42, the oil injection pipe 51 and the oil drain pipe 52 are symmetrically arranged.

[0043] The bottom of the bearing housing 1 is detachably connected to a grader wheel 7, and the fit tolerance between the labyrinth ring 3 and the grader wheel 7 is H7 / g6.

[0044] Specifically, in the sealing structure of an air classifier or mechanical pulverizer, the main shaft 2 is fitted inside the bearing housing 1. On both sides of the bearing housing 1, an oil baffle ring 11, a bearing component 12, and a bearing cover 14 are coaxially assembled with the main shaft 2. The bearing cover 14 includes an upper bearing cover 14 and a lower bearing cover 14 assembled on both sides of the bearing housing 1. A labyrinth ring 3 is assembled near the lower bearing cover 14. On the side of the bearing housing 1 near the labyrinth ring 3, a classifier 7 is also coaxially assembled with the main shaft 2. The labyrinth ring 3 is located outside the bearing housing 1 and is a sealing structure used to prevent particulate matter from entering the interior of the bearing housing 1.

[0045] It should also be noted that after the various components of the sealing structure are assembled, they will naturally form an oil passage with the main shaft 2 or adjacent components. The oil passage is connected to the oil channel 5. The function of the oil passage is to guide the lubricating grease to the sealing structure to achieve the lubrication effect. The oil injection pipe 51 can also be connected to the oil passage and together with the oil drain pipe 52, they form a circuit.

[0046] During equipment operation, lubricating grease is injected into the oil injection pipe 51 and compressed air is introduced into the air intake pipe 41. The lubricating grease can evenly enter the bearing component 12 through the oil passage 5 to lubricate various parts and improve the lubrication effect of the bearing. Preferably, the oil injection hole diameter of the oil injection pipe 51 is 3mm-6mm, the diameter of the oil discharge pipe 52 is 8mm-12mm, and the inner circumferential wall of the oil discharge pipe 52 is coated with an anti-corrosion coating. The oil discharge pipe 52 is also equipped with a valve to conveniently control the discharge of waste grease and improve the ease of operation of the equipment. Preferably, the lubricating grease is an extreme pressure composite lithium-based grease with a dropping point of not less than 200℃ and a cone penetration of 265~295 (0.1mm). The extreme pressure composite lithium-based grease has good high temperature resistance, water resistance and extreme pressure anti-wear performance, which can meet the lubrication requirements of the bearing under high temperature and heavy load conditions.

[0047] When the intake pipe 41 injects compressed air into the air passage 4, the pressure range of the air passage 4 is 0.05 to 0.1 MPa, and the flow rate of the injected compressed air is 5 to 10 L / min. Within this pressure range and flow rate, the stability and effectiveness of the positive pressure air cushion can be guaranteed, effectively preventing particulate matter and lubricating grease from entering the sealing gap. The injected compressed air can be discharged from the exhaust pipe 42.

[0048] Example 2

[0049] like Figure 3 and Figure 4 As shown, in this embodiment, it is an improvement based on embodiment 1, with several guide vanes 6 arranged in a ring along the axis of the upper sealing cover 31 inside the air passage 4.

[0050] Several diaphragms are arranged equidistantly around the two side walls of the airway 4, with adjacent diaphragms on opposite sides contracting toward the airway 4 or expanding outward.

[0051] A filter screen is installed at one end of the oil passage 5 near the oil injection pipe 51, and a filter element is installed near the filter screen in the oil passage 5.

[0052] Specifically, the guide vanes 6 inside the air passage 4 are spirally distributed along the axis of the upper sealing cover 31. After compressed air enters the air passage 4, the spiral guide vanes 6 cause the gas to form a tangential velocity in the circumferential direction, significantly reducing the penetration rate of particles generated by the bottom classifier wheel 7 and preventing them from entering the sealing structure and causing wear. In addition, diaphragms that contract or expand towards the air passage 4 are also provided at intervals inside the air passage 4. After compressed air enters the air passage 4, the diaphragm in the contraction section can locally accelerate the compressed air, and the diaphragm in the expansion section can reduce the pressure of the compressed air to a certain extent, realizing intermittent local acceleration or depressurization, achieving the effect of local particle removal, and greatly reducing the probability of particles entering the sealing structure.

[0053] The filter screen and filter element can filter the lubricating grease introduced into the oil injection pipe 51 or the lubricating grease in the oil passage 5, preventing some particles from entering the oil passage 5 and causing blockage, reducing the lubrication of the sealing structure. The filter element can preferably be a replaceable filter paper, and the filter element can be replaced at the same time when the labyrinth ring 3 is disassembled for cleaning.

[0054] Example 3

[0055] The opening width of airway 4 is 2mm-5mm, the opening depth of airway 4 is 1mm-3mm, and the longitudinal cross-sectional shape of airway 4 is rectangular or trapezoidal.

[0056] The labyrinth ring 3 is made of wear-resistant alloy steel, and its hardness is 45HRC-50HRC.

[0057] Specifically, the labyrinth ring 3 is preferably made of wear-resistant alloy steel with a surface hardness of 45HRC-50HRC. The fit tolerance between the labyrinth ring 3 and the classifier 7 is H7 / g6, which ensures that the gap between the labyrinth ring 3 and the classifier 7 is appropriate. This effectively prevents particles from entering without affecting the normal operation of the classifier 7. The wear-resistant alloy steel material and surface hardness can improve the wear resistance of the labyrinth ring 3 and extend its service life.

[0058] A sealing ring is installed at the connection between the intake pipe 41 and the inlet of the air passage 4 to seal and prevent the injected compressed air from leaking, allowing the compressed air to flow along the annular air passage 4. The width of the air passage 4 is 2mm-5mm, the opening depth of the air passage 4 is 1mm-3mm, and the longitudinal cross-sectional shape of the air passage 4 is rectangular or trapezoidal. This ensures that the compressed air forms a stable airflow in the annular positive pressure air passage 4, effectively preventing particulate matter and lubricating grease from entering the sealing gap.

[0059] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An oil-gas sealing structure for air classifier and mechanical crushing classification, comprising a main shaft (2) and a bearing housing (1), and bearing components (12), an oil retaining ring (11), an elastic retaining ring (13), a bearing cover (14), and a sealing ring coaxially assembled with the main shaft (2), characterized in that, It also includes a maze ring (3), in which an air passage (4) is provided, and an air inlet pipe (41) is connected to the bearing seat (1), and the air inlet pipe (41) and the air passage (4) are connected.

2. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 1, characterized in that: The labyrinth ring (3) includes an upper sealing cover (31) and a lower sealing cover (32) that interlock with each other. The diameter of the upper sealing cover (31) gradually decreases from the top surface to the bottom surface. Several guide grooves are provided on the outer peripheral wall of the upper sealing cover (31). Several steps that cooperate with the guide grooves are formed on the inner peripheral wall of the lower sealing cover (32) from the top surface to the bottom surface. An oil passage (5) is provided on the top surface of the lower sealing cover (32) facing downward. A baffle is provided on the top surface of the oil passage (5). The air passage (4) is annular and located between the baffle and the inner peripheral wall of the lower sealing cover (32).

3. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 2, characterized in that: The bearing housing (1) is connected to an oil injection pipe (51), which is connected to the oil passage (5). The top edge of the upper sealing cover (31) extends downward toward the partition and is fastened to the partition.

4. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 2, characterized in that: Several guide vanes (6) are arranged in a ring along the axis of the upper sealing cover (31) inside the air passage (4).

5. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 4, characterized in that: Several diaphragms are equidistantly arranged around the two side walls of the airway (4), and the adjacent diaphragms on the opposite side contract toward the airway (4) or expand outward.

6. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 1, characterized in that: The bottom of the bearing housing (1) is detachably connected to a grading wheel (7), and the fit tolerance between the labyrinth ring (3) and the grading wheel (7) is H7 / g6.

7. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 3, characterized in that: The air passage (4) is also connected to the air outlet pipe (42), and the oil passage (5) is also connected to the oil drain pipe (52). The air inlet pipe (41) and the air outlet pipe (42), the oil injection pipe (51) and the oil drain pipe (52) are respectively symmetrically arranged.

8. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 7, characterized in that: A filter screen is provided at one end of the oil passage (5) near the oil injection pipe (51), and a filter element is provided at the oil passage (5) near the filter screen.

9. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 1, characterized in that: The opening depth of the air passage (4) is 2mm-5mm, the opening depth of the air passage (4) is 1mm-3mm, and the longitudinal cross-sectional shape of the air passage (4) is rectangular or trapezoidal.

10. The oil-gas sealing structure for air classifier and mechanical crushing classification according to claim 1, characterized in that: The labyrinth ring (3) is made of wear-resistant alloy steel and has a hardness of 45HRC-50HRC.

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