Machine base sealing device for positive-pressure direct-blowing medium-speed coal mill
By designing a base sealing device for medium-speed coal mills, including adjustable material retaining ring and sealing ring assembly, the problem of sealing failure of medium-speed coal mills in high temperature and high pollution environments is solved, and effective sealing effect and environmental pollution reduction are achieved.
Patent Information
- Application Number
- CN202420856467.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-23
- Publication Date
- 2025-05-06
- Estimated Expiration
- 2034-04-23
AI Technical Summary
The base sealing device of the medium-speed coal mill is in a high temperature and high pollution environment, and coal dust accumulates in the original gap, resulting in seal failure, the carbon precision sealing ring wears, and the air leakage increases, causing environmental pollution.
A base sealing device including a sealing device body, an adjustable retaining ring and a sealing ring assembly is designed. The adjustable stop ring is installed on the outside of the upper connecting ring by coaxially with the upper connecting ring, and can be adjusted up and down along its axis direction to form a vertical air duct that isolates external impurities and protects the gap between the transmission disc and the upper connecting ring. The sealing ring assembly includes a carbon precision sealing ring and a rubber sealing ring, which is fixed to the lower connecting ring and close to the outside of the transmission disc to prevent leakage of sealing wind.
Effectively block external impurities such as coal ash into the gap, avoid wear, maintain sealing effect, reduce air leakage and pollutant leakage, and improve the sealing performance of the lower part of the transmission disc.
Smart Images
Figure CN222836253U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of sealing structures of machine bases of medium-speed coal mills, in particular to a machine base sealing device for positive-pressure direct-blowing medium-speed coal mills. Background Art
[0002] The medium-speed roller coal mill is the core equipment in the positive pressure direct-blowing pulverizing system of the coal-fired power plant boiler combustion. The base sealing device in the medium-speed roller coal mill acts on the dynamic and static gaps between the base and the transmission disc of the rotating component. The sealing device can form a cavity with sealed air passing through it with the base top plate and the transmission disc; in the primary air chamber, the temperature of the primary air is often above 200℃, and the primary air is also mixed with coal ash in the boiler flue gas and solid particle impurities that are difficult to grind that fall from the grinding area of the coal mill to the primary air chamber. There is a certain gap between the disks, and the gap is not processed in the original machine base sealing device. Often in the later operation process, the small particles of coal powder accumulated in the gap will cause wear of the parts, and eventually the gap will increase and cannot prevent a large amount of coal ash from entering the sealed chamber, which will cause the carbon sealing ring to wear successively, making it easier for the primary air to carry coal powder into the chamber, and the coal ash particles enter the gap between the carbon sealing ring and the transmission disk, aggravating the wear between the carbon ring and the transmission disk, increasing the air leakage, causing hot air and pollutants such as coal ash to leak from the machine base seal, causing environmental pollution. Utility Model Content
[0003] The utility model aims to provide a machine base sealing device for a positive pressure direct blowing medium speed coal mill to solve the problems raised in the above background technology.
[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a machine base sealing device for a positive pressure direct blowing medium speed coal mill, wherein the machine base sealing device can cooperate with a transmission disc and a machine base top plate to form a cavity, wherein the machine base sealing device comprises a sealing device body, an adjustable material retaining ring and a sealing ring assembly, wherein the sealing device body comprises an upper connecting ring and a lower connecting ring coaxially sleeved on the transmission disc in sequence along the axial direction of the transmission disc, and the upper connecting ring is sealingly fixedly connected to the lower connecting ring, an end of the lower connecting ring away from the upper connecting ring is sealingly fixedly connected to the machine base top plate, an end of the upper connecting ring away from the lower connecting ring forms a gap with the protruding end of the upper part of the transmission disc, and the gap allows the transmission disc to be sealed. Relative to the rotation of the sealing device body around its own axis, the adjustable stop ring is coaxial with the upper connecting ring and is installed on the outer side of the upper connecting ring. The adjustable stop ring can be adjusted up and down along its axial direction. At the same time, a vertical air duct that can isolate external impurities and is connected to the gap is formed between the adjustable stop ring and the upper connecting ring. The end of the adjustable stop ring away from the lower connecting ring is close to the protruding end. The sealing ring assembly includes a plurality of groups of carbon sealing rings and a group of rubber sealing rings that are coaxially mounted on the transmission disk in sequence along the axial direction of the transmission disk. The carbon sealing ring and the rubber sealing ring are both fixed to the lower connecting ring, and the carbon sealing ring and the rubber sealing ring are close to the outer side of the transmission disk.
[0005] Based on the above technical features, the utility model protects the gap between the transmission disc and the upper connecting ring through an adjustable material retaining ring, and blocks foreign impurities such as coal ash carried by the primary wind outside the gap. Moreover, when a small gap appears between the adjustable material retaining ring and the transmission disc, the adjustable material retaining ring can be adjusted up and down in time to prevent foreign impurities such as coal ash from passing through the small gap and entering the gap between the transmission disc and the upper connecting ring to cause wear there, thereby ultimately preventing the gap between the transmission disc and the upper connecting ring from increasing due to wear. At the same time, the carbon sealing ring and the rubber sealing ring can block the leakage of sealing wind in the cavity, maintain the sealing wind pressure inside the cavity, and improve the sealing performance of the lower part of the transmission disc.
[0006] Preferably in the present technical solution, the adjustable retaining ring is provided with a plurality of annular grooves at one end away from the lower connecting ring, and sealing materials are installed in the grooves. The sealing materials are used to isolate external impurities from entering the gap; preferably, the sealing materials are square graphite packing.
[0007] Based on the above technical features, the utility model selects square graphite packing with good high temperature resistance as sealing material, which can be extremely suitable for high temperature environments with temperatures above 200°C.
[0008] Preferably in the present technical solution, the upper connecting ring comprises an upper connecting ring body and an annular flange arranged on the outer side of the upper connecting ring body, and one end of the adjustable retaining ring away from the annular groove is installed on the annular flange through a plurality of adjusting screws.
[0009] Based on the above technical features, the use of an adjusting screw can more easily adjust the upper and lower positions of the adjustable retaining ring, thereby facilitating the adjustment of the gap between the protruding end of the transmission disk and the upper side of the adjustable retaining ring.
[0010] Preferably in the present technical solution, the adjustable material retaining ring can be equally divided into a number of arc segments, and both ends of each arc segment are connected and fixed by a first bolt.
[0011] Based on the above technical features, the adjustable material retaining ring is equally divided into a number of arc segments, and the several arc segments are then assembled together by bolts, which greatly improves the convenience of installation and also saves work time and cost.
[0012] Preferably in the present technical solution, multiple groups of the carbon sealing rings are fixedly connected to the lower connecting ring by second bolts, and the carbon sealing rings include a carbon ring and a carbon sealing seat, and the carbon sealing seat cooperates with the transmission disk to form a first ring groove, and the carbon ring is placed in the first ring groove; preferably, a spring that is connected to the carbon ring is also provided in the first ring groove, and the spring is used for squeezing the carbon ring to the outer side of the transmission disk to ensure the sealing effect of the machine base sealing device.
[0013] Preferably in the present technical solution, the rubber sealing ring is fixedly connected to the carbon sealing ring by a third bolt, the rubber sealing ring comprises a rubber sealing ring and a rubber sealing seat, the rubber sealing seat and the transmission disc cooperate to form a second ring groove, and the rubber sealing ring is placed in the second ring groove; preferably, the rubber sealing seat and the carbon sealing seat cooperate to form a threaded hole at an end away from the transmission disc, and the grease filling port is connected through the threaded hole.
[0014] Based on the above technical features, after the rubber sealing ring is lubricated by the grease injected through the grease filling port, the wear between the rubber sealing ring and the transmission plate can be effectively reduced. At the same time, the rubber sealing ring lubricated with grease can also better prevent the leakage of sealing air in the cavity.
[0015] Preferably in the present technical solution, the carbon sealing ring and the rubber sealing ring are equally divided into a number of arc segments, and both ends of each arc segment are connected and fixed by pins.
[0016] Based on the above technical features, the carbon sealing ring and the rubber sealing ring are equally divided into a number of arc segments, which are then assembled together through pins, thereby greatly improving the convenience of installation and saving labor time and costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a structural schematic diagram of a base sealing device for a positive pressure direct blowing medium speed coal mill in an embodiment of the utility model;
[0018] Figure 2 For the utility model embodiment Figure 1 The enlarged schematic diagram of point Ⅰ in the middle;
[0019] Figure 3 For the utility model embodiment Figure 1 Enlarged schematic diagram of point II in the middle.
[0020] In the figure: 1, transmission plate; 1A, protruding end; 2, adjustable retaining ring; 2A, square graphite packing; 2B, groove; 2C, adjusting screw; 3, upper connecting ring; 3A, upper connecting ring body; 3B, annular flange; 4, lower connecting ring; 5, carbon sealing ring; 5A, carbon sealing seat; 5B, carbon ring; 5C, spring; 5D, second bolt; 6, rubber sealing ring; 6A, rubber sealing seat; 6B, rubber sealing ring; 6C, grease filling port; 6D, third bolt; 7, sealed air duct assembly; 8, machine base top plate; 9, first bolt; 10, pin. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0022] It should be noted that, in the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.
[0023] In addition, it should be understood that for the convenience of description, the sizes of various components shown in the drawings are not drawn according to the actual proportional relationship.
[0024] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined or described in one drawing, it will not require further detailed discussion and description in the description of the subsequent drawings.
[0025] like Figures 1 to 3 As shown, the utility model provides a technical solution: a machine base sealing device for a positive pressure direct blowing medium speed coal mill, wherein the machine base sealing device can cooperate with a transmission disc 1 and a machine base top plate 8 to form a cavity, and the machine base sealing device includes a sealing device body, an adjustable material retaining ring 2 and a sealing ring assembly.
[0026] Specific as Figure 1 As shown, the sealing device body includes an upper connecting ring 3 and a lower connecting ring 4 which are coaxially mounted on the transmission disk 1 in sequence along the axial direction of the transmission disk 1, and the upper connecting ring 3 is sealed and fixed to the lower connecting ring 4, and one end of the lower connecting ring 4 away from the upper connecting ring 3 is sealed and fixed to the machine base top plate 8, and one end of the upper connecting ring 3 away from the lower connecting ring 4 forms a gap with the protruding end 1A on the upper part of the transmission disk 1, and the gap allows the transmission disk 1 to rotate around its own axis relative to the sealing device body, and the upper connecting ring 3 and the lower connecting ring 4 are connected and fixed in the sealing docking area using multiple fastening bolts, and one end of the lower connecting ring 4 away from the upper connecting ring 3 is welded and fixed to the machine base top plate 8. At the same time, the upper connecting ring 3 and the lower connecting ring 4 are equally divided into a number of arc segments for easy disassembly and installation, and the head and tail of each arc end are connected and assembled together by a first bolt 9.
[0027] For example Figure 1 As shown, the adjustable material retaining ring 2 is coaxial with the upper connecting ring 3 and is installed on the outer side of the upper connecting ring 3. The adjustable material retaining ring 2 is specifically located at the dynamic and static junction of the transmission disc 1 and the upper connecting ring 3. The adjustable material retaining ring 2 can be adjusted up and down along its axial direction. At the same time, a vertical air duct that can isolate external impurities and is connected to the gap is formed between the inner side surface of the adjustable material retaining ring 2 and the outer side surface of the upper connecting ring 3. The vertical air duct can establish a certain pressure difference between the cavity and the primary air chamber outside the cavity to avoid leakage of coal powder and sealing air inside the cavity due to insufficient pressure difference in the machine base sealing device. The end of the adjustable material retaining ring 2 away from the lower connecting ring 4 is close to the protruding end 1A.
[0028] Further, as Figure 3 As shown, the adjustable retaining ring 2 is provided with a plurality of groups of annular grooves 2B at one end away from the lower connecting ring 4, and sealing materials are installed in the grooves 2B, which can be used to isolate external impurities from entering the gap; in the embodiment of the utility model, the sealing material is selected from square graphite packing 2A, and the square graphite packing 2A has good high temperature resistance and can be extremely suitable for high temperature environments above 200°C. At the same time, two groups of grooves 2B are provided, and square graphite packing 2A are installed in both groups of grooves 2B.
[0029] In the utility model, the gap left between the transmission disc 1 and the upper connecting ring 3 is protected by an adjustable material retaining ring 2 to block foreign impurities such as coal ash carried by the primary wind outside the gap, and when slight wear occurs between the adjustable material retaining ring 2 and the protruding end 1A, the adjustable material retaining ring 2 can be adjusted up and down in time to prevent impurities such as coal ash in the primary air chamber from entering the gap between the transmission disc 1 and the upper connecting ring 3 and causing subsequent wear, thereby increasing the gap between the transmission disc 1 and the upper connecting ring 3 due to wear.
[0030] Further, such as Figure 1 and Figure 2 As shown, the upper connecting ring 3 includes an upper connecting ring body 3A and an annular flange 3B arranged on the outer side of the upper connecting ring body 3A, and the end of the adjustable retaining ring 2 away from the groove 2B is installed on the annular flange 3B through a plurality of adjusting screws 2C, and the upper and lower positions of the adjustable retaining ring 2 can be adjusted by screwing the adjusting screws 2C, so as to facilitate the adjustment of the gap between the protruding end of the transmission disc 1 and the upper side surface of the adjustable retaining ring 2. Specifically, it can be used when the adjustable retaining ring 2 is installed or after long-term use, the gap between the transmission disc 1 and the adjustable retaining ring 2 changes due to the vibration of the transmission disc 1; in the embodiment of the utility model, the annular flange 3B is welded to the outer side surface of the upper connecting ring body 3A, and the welding position of the annular flange 3B can be determined according to the height of the adjustable retaining ring 2.
[0031] Furthermore, the adjustable material retaining ring 2 can be equally divided into a number of arc segments, and both ends of each arc segment are connected and fixed by a first bolt 9 to improve its installation convenience and save labor time and cost.
[0032] Specifically, Figure 1 and Figure 2 As shown, the sealing ring assembly includes a plurality of groups of carbon sealing rings 5 and a group of rubber sealing rings 6 which are coaxially sleeved on the transmission disk 1 in sequence along the axial direction of the transmission disk 1. The carbon sealing rings 5 and the rubber sealing rings 6 are both fixedly connected to the lower connecting ring 4, and the carbon sealing rings 5 and the rubber sealing rings 6 are tightly attached to the outer side of the transmission disk 1. The carbon sealing rings 5 and the rubber sealing rings 6 can block the leakage of the sealing wind in the cavity, maintain the sealing wind pressure inside the cavity, and improve the sealing performance of the lower part of the transmission disk 1. In the embodiment of the utility model, the carbon sealing rings 5 and the rubber sealing rings 6 are equally divided into a plurality of arc segments, and the head and tail ends of each arc segment are connected and fixed by a pin 10.
[0033] Furthermore, multiple groups of carbon sealing rings 5 are fixedly connected to the lower connecting ring 4 by second bolts 5D. The carbon sealing rings 5 include a carbon ring 5B and a carbon sealing seat 5A. The carbon sealing seat 5A cooperates with the transmission plate 1 to form a first ring groove. The carbon ring 5B is placed in the first ring groove. A spring 5C that is connected to the carbon ring 5B is also provided in the first ring groove. The spring 5C is used to squeeze the carbon ring 5B to the outer side surface of the transmission plate 1 to ensure the sealing effect of the machine base sealing device. In the embodiment of the utility model, two groups of upper and lower carbon sealing rings 5 are provided. At the same time, in order to improve the sealing performance of the lower part of the transmission plate 1, more groups of carbon sealing rings 5 can also be provided according to actual conditions.
[0034] Furthermore, the rubber sealing ring 6 is fixedly connected to the carbon sealing ring 5 by a third bolt 6D. The rubber sealing ring 6 includes a rubber sealing ring 6B and a rubber sealing seat 6A. The rubber sealing seat 6A and the transmission plate 1 cooperate to form a second ring groove. The rubber sealing ring 6B is placed in the second ring groove. The rubber sealing seat 6A and the carbon sealing seat 5A cooperate to form a threaded hole at the end away from the transmission plate 1, and the grease filling port 6C is connected through the threaded hole. In the embodiment of the utility model, the third bolt 6D is fixedly connected to the top surface of the second bolt 5D. After the grease injected into the grease filling port 6C lubricates the rubber sealing ring 6B, the wear between the rubber sealing ring 6B and the transmission plate 1 can be effectively reduced. At the same time, the rubber sealing ring 6B lubricated by the grease can also better prevent the leakage of sealing wind in the cavity.
[0035] like Figure 1 As shown, a sealed air duct assembly 7 is also provided at the lower part of the lower connecting ring 4 for introducing sealed air. Since a pressure difference needs to be established between the cavity and the primary air chamber, the sealed air interface in the sealed air duct assembly 7 must be opened before the primary air is opened.
[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A machine base sealing device for a positive pressure direct blowing medium speed coal mill, the machine base sealing device can cooperate with a transmission disc (1) and a machine base top plate (8) to form a cavity, characterized in that: The base sealing device comprises: A sealing device body, the sealing device body comprising an upper connecting ring (3) and a lower connecting ring (4) which are coaxially sleeved on the transmission disc (1) in sequence along the axial direction of the transmission disc (1), and the upper connecting ring (3) and the lower connecting ring (4) are sealed and fixedly connected, one end of the lower connecting ring (4) away from the upper connecting ring (3) is sealed and fixedly connected to the machine base top plate (8), and one end of the upper connecting ring (3) away from the lower connecting ring (4) forms a gap with the protruding end (1A) on the upper part of the transmission disc (1), and the gap allows the transmission disc (1) to rotate around its own axis relative to the sealing device body; An adjustable material retaining ring (2), the adjustable material retaining ring (2) being coaxial with the upper connecting ring (3) and being installed on the outer side of the upper connecting ring (3), the adjustable material retaining ring (2) being adjustable up and down along its axial direction, and a vertical air duct being isolated from external impurities and being connected to the gap is formed between the adjustable material retaining ring (2) and the upper connecting ring (3), and an end of the adjustable material retaining ring (2) away from the lower connecting ring (4) is in close contact with the protruding end (1A); A sealing ring assembly, the sealing ring assembly comprising a plurality of groups of carbon sealing rings (5) and a group of rubber sealing rings (6) which are coaxially sleeved on the transmission disc (1) in sequence along the axial direction of the transmission disc (1), the carbon sealing rings (5) and the rubber sealing rings (6) being fixedly connected to the lower connecting ring (4), and the carbon sealing rings (5) and the rubber sealing rings (6) being tightly attached to the outer side of the transmission disc (1).
2. The machine base sealing device according to claim 1, characterized in that: The adjustable material retaining ring (2) is provided with a plurality of annular grooves (2B) at one end away from the lower connecting ring (4), and sealing materials are installed in the grooves (2B). The sealing materials are used to prevent external impurities from entering the gap.
3. The machine base sealing device according to claim 2, characterized in that: The sealing material is a square graphite packing (2A).
4. The machine base sealing device according to claim 2, characterized in that: The upper connecting ring (3) comprises an upper connecting ring body (3A) and an annular flange (3B) arranged on the outer side of the upper connecting ring body (3A); the end of the adjustable material retaining ring (2) away from the groove (2B) is mounted on the annular flange (3B) via a plurality of adjusting screws (2C).
5. The machine base sealing device according to claim 1, characterized in that: The adjustable material retaining ring (2) can be equally divided into a plurality of arc segments, and both ends of each arc segment are connected and fixed by a first bolt (9).
6. The machine base sealing device according to claim 1, characterized in that: A plurality of groups of carbon sealing rings (5) are fixedly connected to the lower connecting ring (4) via second bolts (5D); the carbon sealing rings (5) comprise a carbon ring (5B) and a carbon sealing seat (5A); the carbon sealing seat (5A) cooperates with the transmission plate (1) to form a first ring groove; the carbon ring (5B) is placed in the first ring groove.
7. The machine base sealing device according to claim 6, characterized in that: A spring (5C) is also provided in the first ring groove and is connected to the carbon ring (5B). The spring (5C) is used to press the carbon ring (5B) to the outer side of the transmission plate (1) to ensure the sealing effect of the machine base sealing device.
8. The machine base sealing device according to claim 6, characterized in that: The rubber sealing ring (6) is fixedly connected to the carbon sealing ring (5) via a third bolt (6D). The rubber sealing ring (6) comprises a rubber sealing ring (6B) and a rubber sealing seat (6A). The rubber sealing seat (6A) cooperates with the transmission plate (1) to form a second ring groove. The rubber sealing ring (6B) is placed in the second ring groove.
9. The machine base sealing device according to claim 8, characterized in that: The rubber seal seat (6A) and the carbon seal seat (5A) cooperate to form a threaded hole at one end away from the transmission plate (1), and the grease filling port (6C) is connected through the threaded hole.
10. The machine base sealing device according to claim 1, characterized in that: The carbon sealing ring (5) and the rubber sealing ring (6) are equally divided into a plurality of arc segments, and the first and second ends of each arc segment are connected and fixed by a pin (10).