Self-cleaning filtering device for hot pressing sintering machine

Abstract

The utility model discloses a self-cleaning filtering device for a hot pressing sintering machine, and belongs to the technical field of diamond tool manufacturing equipment. The mold comprises a self-cleaning dust removal assembly, and the self-cleaning dust removal assembly comprises a sealing cover, a three-stage filtering device, a pulse blowback device and a dust treatment device. The pulse blowback device comprises a gas storage tank and a nitrogen pulse generator; the waste heat recovery assembly comprises a spiral air outlet pipeline. According to the self-cleaning filtering device for the hot pressing sintering machine, a double-layer sealing cover is combined with a three-stage filtering device to achieve totally-closed operation in the sintering process, the pulse back-blowing device blows air reversely through nitrogen pulses and is matched with control of a one-way sealing valve in the air storage tank, filtering materials can be self-cleaned under the non-stop condition, the filtering device is prevented from being blocked, and the service life of the filtering device is prolonged. In addition, the spiral gas outlet pipeline surrounds the outer wall of the gas storage tank, nitrogen in the tank is preheated through high-temperature waste gas, the waste heat utilization rate is increased, comprehensive energy consumption is reduced, meanwhile, the back flushing nitrogen temperature is low, a filter bag cannot be damaged, and the service life of a filter material is greatly prolonged.

Description

Technical Field

[0001] This utility model relates to the technical field of diamond tool manufacturing equipment, and in particular to a self-cleaning filter device for a hot pressing sintering machine. Background Technology

[0002] The diamond cutting tool hot pressing sintering machine is a core piece of equipment in the diamond tool manufacturing industry. It uses a hot pressing sintering process to form a dense structure of diamond particles or diamond cutting tool blanks with metal binders (such as cobalt and nickel-based alloys) under high temperature and high pressure.

[0003] Most existing hot-pressing sintering workshops in factories employ an open structure, leading to the direct escape of heavy metal dust (such as WC and Co) and polycyclic aromatic hydrocarbon gases generated during the sintering process. PM2.5 concentrations in these workshops often exceed 200 μg / m³, far exceeding occupational exposure limits, posing a high health risk to workers. Existing dust collection systems for hot-pressing sintering machines are mostly directly connected to bag filters. However, bag filters have poor heat resistance, and the high temperatures generated during hot-pressing sintering (above 600℃) damage the filter bags, resulting in frequent filter replacements that require machine shutdown, which is extremely inconvenient. To address these issues, we propose a self-cleaning filtration device for hot-pressing sintering machines. Utility Model Content

[0004] The purpose of this invention is to provide a self-cleaning filter device for a hot press sintering machine, so as to solve the problems of serious dust pollution, low waste heat utilization rate, poor high temperature resistance of dust removal system and frequent maintenance in existing hot press sintering machines.

[0005] To solve the above-mentioned technical problems, this utility model provides a self-cleaning filtration device for a hot pressing sintering machine, including a self-cleaning dust removal component, including a sealing cover, a three-stage filtration device, a pulse backflushing device, and a dust treatment device.

[0006] The pulse backflushing device includes a gas storage tank and a nitrogen pulse generator connected to the gas storage tank;

[0007] The waste heat recovery assembly includes a spiral exhaust pipe that surrounds the outer wall of the gas storage tank and is used to preheat the gas inside the gas storage tank with high-temperature waste gas.

[0008] Preferably, the sealing cover has a double-layer structure, with the inner layer being a 1.5mm thick stainless steel corrugated plate and the outer layer being a 3mm thick heat-resistant steel plate, with heat insulation cotton filling between the two layers.

[0009] Preferably, the top surface of the sealing cover has two connecting holes, which are respectively connected to the pulse backflushing device and the dust treatment device.

[0010] Preferably, the three-stage filtration device includes a primary filtration layer, a secondary filtration layer, and a tertiary filtration layer arranged sequentially along the airflow direction;

[0011] The primary filter layer is a porous ceramic plate with a pore size of 40±10μm and a porosity of 30-40%.

[0012] The secondary filter layer is a sintered metal fiber felt with a fiber diameter of 5±1μm;

[0013] The three-stage filtration layer is a ceramic filter membrane with a pore size of 1±0.2μm and a porosity of 20-25%.

[0014] Preferably, the gas storage tank is equipped with a one-way sealing valve, which only allows the nitrogen pulse generator to blow gas in reverse to the three-stage filtration device, and the spiral gas outlet pipe is closed during backflushing.

[0015] Preferably, the self-cleaning dust removal component further includes an isolation cover, which is driven to rise and fall by an electric telescopic rod, and a sealing ring is provided on the contact surface between the isolation cover and the sealing cover.

[0016] Preferably, the dust treatment device includes a connecting bend, a dust collection chamber, and an air outlet; the dust collection chamber is densely packed with dust filter bags.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] 1. The self-cleaning filter device for hot pressing sintering machine of this utility model is designed by setting a spiral exhaust pipe around the outer wall of the gas storage tank, using high-temperature exhaust gas (400-600℃) to preheat the nitrogen in the tank to 80-120℃, which greatly improves the waste heat utilization rate and reduces the overall energy consumption. At the same time, the nitrogen carrying dust in the back-flushing is at a lower temperature, so it will not damage the filter bag when passing through the dust removal filter bag with poor heat resistance, which greatly extends the filter material life and significantly reduces the maintenance frequency.

[0019] 2. The self-cleaning filter device for hot pressing sintering machine of this utility model adopts a double-layer sealing cover (inner layer 1.5mm stainless steel corrugated plate + outer layer 3mm heat-resistant steel plate), combined with a three-stage filtration device (porous ceramic plate, metal fiber sintering felt, ceramic filter membrane), to achieve fully enclosed operation of the sintering process. The PM2.5 concentration in the workshop is reduced from 200μg / m³ to below 50μg / m³. The pulse backflushing device uses nitrogen pulse reverse blowing, combined with the one-way sealing valve in the gas storage tank, to self-clean the filter material without stopping the machine, preventing the filter device from clogging. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a self-cleaning filter device for a hot pressing sintering machine provided by this utility model;

[0021] Figure 2This is a front view of a self-cleaning filter device for a hot pressing sintering machine provided by this utility model;

[0022] Figure 3 This is a partial cross-sectional view of a self-cleaning dust removal component in a self-cleaning filter device for a hot pressing sintering machine provided by this utility model;

[0023] In the diagram: 1. Self-cleaning dust removal component; 101. Sealing cover; 101c. Connecting hole; 102. Three-stage filtration device; 102a. Primary filter layer; 102b. Secondary filter layer; 102c. Tertiary filter layer; 103. Pulse backflushing device; 103a. Air storage tank; 103a-1. One-way sealing valve; 103b. Nitrogen pulse generator; 104. Dust treatment device; 104a. Connecting bend; 104b. Dust collection chamber; 104c. Air outlet; 104d. Dust collection filter bag; 105. Isolation cover; 105a. Electric telescopic rod; 105b. Sealing ring; 2. Waste heat recovery component; 201. Spiral exhaust pipe. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0025] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Example

[0027] This utility model provides a self-cleaning filter device for a hot pressing sintering machine. Please refer to [link / reference]. Figures 1-3 The system includes a self-cleaning dust removal component 1, which includes a sealing cover 101, a three-stage filtration device 102, a pulse backflushing device 103, and a dust treatment device 104; the pulse backflushing device 103 includes a gas storage tank 103a and a nitrogen pulse generator 103b connected to the gas storage tank 103a; and a waste heat recovery component 2, which includes a spiral exhaust pipe 201, which surrounds the outer wall of the gas storage tank 103a and is used to preheat the gas inside the gas storage tank with high-temperature waste gas.

[0028] The sealing cover 101 has a double-layer structure, with the inner layer being a 1.5mm thick stainless steel corrugated plate and the outer layer being a 3mm thick heat-resistant steel plate, with heat insulation cotton filling between the two layers; the top surface of the sealing cover 101 has two connecting holes 101a, which are respectively connected to the pulse backflushing device 103 and the dust treatment device 104.

[0029] The three-stage filtration device 102 includes a primary filtration layer 102a, a secondary filtration layer 102b, and a tertiary filtration layer 102c arranged sequentially along the airflow direction; the primary filtration layer 102a is a porous ceramic plate with a pore size of 40±10μm and a porosity of 30-40%; the secondary filtration layer 102b is a sintered metal fiber felt with a fiber diameter of 5±1μm; and the tertiary filtration layer 102c is a ceramic filter membrane with a pore size of 1±0.2μm and a porosity of 20-25%.

[0030] The gas storage tank 103a is equipped with a one-way sealing valve 103a-1, which only allows the nitrogen pulse generator 103b to blow air in the reverse direction to the three-stage filtration device 102, and the spiral exhaust pipe 201 is closed when backflushing; the self-cleaning dust removal assembly 1 also includes an isolation cover 105, which is driven to rise and fall by an electric telescopic rod 105a, and a sealing ring 105b is provided on the contact surface between the isolation cover 105 and the sealing cover 101; the dust treatment device 104 includes a connecting bend pipe 104a, a dust collection chamber 104b, and an air outlet 104c; the dust collection chamber 104b is densely packed with dust collection filter bags 104d.

[0031] It should be noted that the inner layer of the sealing cover 101 is a 1.5mm thick stainless steel corrugated plate with a temperature resistance of 1000℃ and a corrugation depth of 8mm. The outer layer is a 3mm thick heat-resistant steel plate with a high-temperature resistant black paint coating. The interlayer is filled with heat insulation cotton.

[0032] Preferably, the three-stage filtration device 102 is fixed to the top of the sealing cover 101 by a flange, and is divided into three filtration layers from bottom to top: the first-stage filtration layer 102a is a porous ceramic plate with a thickness of 10 mm, a pore size of 40 μm, and a porosity of 40%; the second-stage filtration layer 102b is a metal fiber sintered felt with a fiber diameter of 5 μm and a thickness of 30 mm; and the third-stage filtration layer 102c is a ceramic filter membrane with a thickness of 5 mm, a pore size of 1 μm, and a porosity of 25%.

[0033] Preferably, the gas storage tank 103a is made of 304 stainless steel and has a built-in one-way sealing valve 103a-1 at the inlet, which is pressure-resistant to 1MPa. The nitrogen pulse generator 103b pressurizes the preheated nitrogen in the gas storage tank 103a and blows it into the three-stage filter device 102. The pulse generator is equipped with a pressure regulating valve and a pressure sensor, and integrates a PLC controller to support multi-condition triggering pulses (differential pressure, temperature, time, on / off status, etc.) and pulse parameter settings (pressure, duration, interval time, etc.), realizing fully automatic backflushing without manual intervention. The pulse parameters are precisely adjusted to adapt to different dust load scenarios.

[0034] Preferably, in the dust treatment device 104, the connecting bend 104a is a stainless steel pipe, connecting the isolation cover 105 and the dust collection chamber 104b. There is a cover plate at the connection with the isolation cover 105. The cover plate is controlled by a solenoid valve. When the inside of the isolation cover 105 is completely isolated from the inside of the sealing cover 101, the cover plate opens and the self-cleaning process begins. 32 dust collection filter bags 104d are installed inside the dust collection chamber 104b. The dust collection filter bags 104d adopt a vertically suspended bag structure. The main body of the filter bag is a cylindrical polytetrafluoroethylene (PTFE) membrane filter material. When the dust-laden flue gas passes through the filter bag, the dust will be trapped on the outer surface of the filter bag. The purified gas passes through the filter bag and enters the bag, and finally is discharged through the air outlet 104c. The dust collection filter bags 104d need to be cleaned and maintained regularly, generally 30 minutes after the equipment is stopped.

[0035] Preferably, in the waste heat recovery component 2, the outlet pipe 201 consists of two spiral copper pipes, which spiral around the outer wall of the gas storage tank 103a three times to preheat the nitrogen in the gas storage tank 103a through heat exchange. The pipes are connected to the exhaust port via a flange. Preheating the nitrogen in the gas storage tank 103a produces the following beneficial effects: 1. After preheating the nitrogen to 80-120℃, its density decreases by approximately 30% (the density of nitrogen at room temperature is 1.25 kg / m³ → 1. After preheating, the flow rate is approximately 0.9 kg / m³, and the flow rate increases by 20-30% under the same pressure. During pulse backflushing, the airflow penetration is stronger, and the dust removal rate is improved. 2. It reduces the thermal shock of materials. During the sintering process, the temperature of the three-stage filter device 102 can reach 300-400℃. If room temperature nitrogen (25℃) is directly injected, the ceramic filter membrane 102c is prone to micro-cracks due to sudden cooling (caused by the difference in thermal expansion coefficient). Preheating nitrogen reduces the temperature difference, effectively reduces thermal stress, and helps protect the filter device and improve its service life. 3. Preheating the nitrogen in the tank helps to keep the nitrogen temperature in the tank above the dew point, which can avoid the formation of condensate when cold nitrogen enters the high-temperature environment and prevent the dust filter bag 104d from becoming damp and hardened or the metal parts from rusting.

[0036] In use, the hot pressing sintering machine also includes a pressurizing device, a heating device, and supporting control structures. First, it requires loading and pre-pressing, followed by hot pressing sintering. During the hot pressing sintering process, the cover leading to the dust treatment device 104 remains closed. The flue gas generated during hot pressing can only exit the sealing cover 101 through the three-stage filtration device 102. Due to the presence of the one-way sealing valve 103a-1, the filtered flue gas cannot enter the gas storage tank and can only be discharged through the exhaust pipe 201. During discharge, the spiral exhaust pipe 201 surrounds the outer wall of the gas storage tank 103a. Heat exchange preheats the nitrogen gas in the tank to 80-120℃. Under the following conditions, the pulse backflushing device 103 starts to perform self-cleaning: 1. When the pressure difference between the upper and lower sides of the three-stage filter device 102 is ≥800pa, the nitrogen pulse generator 103b backflushes at a pressure of 0.5MPa for 200ms; 2. When the temperature in the sintering chamber drops below 400℃, it backflushes at a pressure of 0.3MPa for 100ms; 3. Before the hot pressing sintering machine is turned off, a preventive backflushing is automatically performed at a pressure of 0.4MPa for 150ms.

[0037] During backflushing, the hot pressing sintering machine stops working and stands still for 5-10 minutes. Then, the isolation cover 105 is raised by the electric telescopic rod 105a and placed on the top surface of the sealing cover 101. It is separated from the sealing cover 101 by the pressed sealing ring 105b. At the same time, the cover plate leading to the dust treatment device 104 is opened and the air outlet pipe 201 is closed. The nitrogen pulse generator 103b starts backflushing according to the set conditions, blowing air in the opposite direction to the three-stage filtration device 102, blowing away the dust adsorbed on the filter layer. The dust is blown into the dust removal chamber 104b through the isolation cover 105 and the connecting bend pipe 104a. After being adsorbed by multiple dust removal filter bags 104d, it is finally purified and discharged from the air outlet 104c.

[0038] In summary, the self-cleaning filter device for hot pressing sintering machines of this invention utilizes a spiral exhaust pipe surrounding the outer wall of the gas storage tank. High-temperature exhaust gas (400-600℃) preheats the nitrogen gas inside the tank to 80-120℃, significantly improving waste heat utilization and reducing overall energy consumption. Simultaneously, the low-temperature nitrogen carrying dust during backflushing prevents damage to the poorly heat-resistant dust filter bags, greatly extending filter media lifespan and significantly reducing maintenance frequency. Furthermore, the use of a double-layer sealing cover (inner 1.5mm stainless steel corrugated plate + outer 3mm heat-resistant steel plate), combined with a three-stage filtration device (porous ceramic plate, metal fiber sintered felt, ceramic filter membrane), achieves fully enclosed operation during the sintering process. The workshop PM2.5 concentration is reduced from 200μg / m³ to below 50μg / m³. The pulse backflushing device uses nitrogen pulses (0.3-0.5MPa) to blow air in reverse, controlled by a one-way sealing valve inside the gas storage tank, enabling self-cleaning of the filter media without shutting down the machine and preventing clogging of the filter device.

[0039] The above description is only a description of the preferred embodiment of the present utility model and is not intended to limit the scope of the present utility model in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A self-cleaning filtration device for a hot press sintering machine, characterized in that, The utility model relates to a self-cleaning dust removal assembly (1) comprising a sealed cover (101), a three-stage filter device (102), a pulse back flushing device (103), and a dust treatment device (104). The pulse back flushing device (103) comprises a gas storage tank (103a) and a nitrogen pulse generator (103b) connected to the gas storage tank (103a). The waste heat recovery assembly (2) comprises a spiral gas outlet pipe (201) surrounding the outer wall of the gas storage tank (103a) for preheating the gas in the gas storage tank by high-temperature exhaust gas. The sealed cover (101) has a double-layer structure, with a 1.5 mm thick stainless steel corrugated plate as the inner layer and a 3 mm thick heat-resistant steel plate as the outer layer, and the space between the two layers is filled with thermal insulation cotton.

2. A self-cleaning filter device for a hot press sintering machine as claimed in claim 1, characterized in that Two communication holes (101a) are formed on the top surface of the sealed cover (101) and are respectively connected to the pulse back flushing device (103) and the dust treatment device (104).

3. A self-cleaning filter device for a hot press sintering machine as claimed in claim 2, characterized in that The three-stage filter device (102) comprises a first-stage filter layer (102a), a second-stage filter layer (102b), and a third-stage filter layer (102c) arranged in sequence along the gas flow direction.

4. A self-cleaning filter apparatus for a hot press sintering machine as claimed in claim 1, wherein, The first-stage filter layer (102a) is a porous ceramic plate with a pore size of 40±10 μm and a porosity of 30-40%. The second-stage filter layer (102b) is a metal fiber sintered felt with a fiber diameter of 5±1 μm. The third-stage filter layer (102c) is a ceramic filter membrane with a pore size of 1±0.2 μm and a porosity of 20-25%. The gas storage tank (103a) is provided with a one-way sealing valve (103a-1) that only allows the nitrogen pulse generator (103b) to blow back to the three-stage filter device (102), and the spiral gas outlet pipe (201) is closed during back flushing.

5. A self-cleaning filter apparatus for a hot press sintering machine as claimed in claim 1, wherein, The self-cleaning dust removal assembly (1) further comprises an isolation cover (105) driven to rise and fall by an electric telescopic rod (105a), and the contact surface of the isolation cover (105) with the sealed cover (101) is provided with a sealing ring (105b).

6. A self-cleaning filter apparatus for a hot press sintering machine as claimed in claim 1, wherein, The dust treatment device (104) comprises a communication bend (104a), a dust removal bin (104b), and an air outlet (104c), and the dust removal bin (104b) is densely arranged with dust removal filter bags (104d).

7. A self-cleaning filter apparatus for a hot press sintering machine as claimed in claim 6, wherein, ​

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