A two-stage series nitrogen heating and pressure control ultrafine alloy powder production device

Abstract

This utility model discloses a two-stage series nitrogen heating and pressure control ultrafine alloy powder production device, including a nitrogen supply module, a heating module, a pressure control module, and an atomization reaction module. The heating module is a two-stage series heating module, with the set heating temperature of the second-stage heater being higher than that of the first-stage heater. The input end of the first-stage heater is connected to the output end of the nitrogen supply module through an inlet pipe, and the output end of the second-stage heater is connected to the air inlet of the atomization reaction module through an outlet pipe. A temperature sensor is installed on the outlet pipe. The pressure control module includes an inlet pressure switch, an outlet pressure switch, and an electronic pressure regulating valve. The inlet pressure switch is located on the inlet pipe, and the outlet pressure switch is located on the outlet pipe. The electronic pressure regulating valve is linked to the inlet pressure switch; when the pressure exceeds the set range, the electronic pressure regulating valve automatically adjusts the nitrogen input. This utility model has the advantages of high heating efficiency and stable temperature and pressure.

Description

Technical Field

[0001] This utility model relates to the field of powder metallurgy technology, specifically a two-stage series nitrogen heating and pressure control ultrafine alloy powder production device. Background Technology

[0002] Ultrafine alloy powder (average particle size ≤ 5 μm) is a key raw material for preparing high-precision powder metallurgy components in the aerospace field. Its quality directly depends on the temperature stability and pressure controllability of nitrogen during atomization. In traditional ultrafine alloy powder production, nitrogen heating often uses a single heater, which suffers from low heating efficiency and easy temperature fluctuations, making it difficult to maintain a stable process temperature of 500℃, resulting in powder particle size deviations exceeding 15%. At the same time, pressure control often relies on manual adjustment, with long response times (≥ 1 s) and a tendency for sudden pressure changes, further exacerbating powder particle segregation.

[0003] Although some improved solutions attempted to use multiple heating units, most of them were parallel structures, which did not form a stepped heating. The temperature difference between the two sets of heaters was too large (≥150℃), resulting in uneven heating of nitrogen. Furthermore, pressure detection was only set at a single node, which could not provide real-time feedback on the overall pressure status of the system. This still could not solve the core problem of coordinated stability of temperature and pressure, thus limiting the high-quality large-scale production of ultrafine alloy powder. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a two-stage series nitrogen heating and pressure control ultrafine alloy powder production device with simple structure, high heating efficiency, and stable temperature and pressure.

[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0006] A two-stage series-connected ultrafine alloy powder production device with nitrogen heating and pressure control includes a nitrogen supply module, a heating module, a pressure control module, and an atomization reaction module. The heating module is a two-stage series-connected heating module, including a primary heater and a secondary heater connected in series. The set heating temperature of the secondary heater is higher than that of the primary heater. The input end of the primary heater is connected to the output end of the nitrogen supply module via an inlet pipe, and the output end of the secondary heater is connected to the inlet of the atomization reaction module via an outlet pipe. A temperature sensor is installed on the outlet pipe. The pressure control module includes an inlet pressure switch, an outlet pressure switch, and an electronic pressure regulating valve. The inlet pressure switch and the electronic pressure regulating valve are both installed on the inlet pipe, and the outlet pressure switch is installed on the outlet pipe. The electronic pressure regulating valve is linked to the inlet pressure switch; when the pressure exceeds the set range, the electronic pressure regulating valve automatically adjusts the nitrogen input.

[0007] As a further improvement to the above technical solution:

[0008] Preferably, the set heating temperature of the primary heater is 280-320℃, and the set heating temperature of the secondary heater is 500℃.

[0009] Preferably, the tubes of both the primary heater and the secondary heater are made of stainless steel, with an inner diameter of 50-60mm, a heating wire inside the tube, and a 0.15-0.2mm thick high-temperature resistant insulating layer coated on the inner wall of the tube; the length of the primary heater is 1.0-1.2m, and the length of the secondary heater is 1.2-1.4m.

[0010] Preferably, the primary heater and the secondary heater are connected by a high-temperature resistant pipeline and a sealing connection is achieved using a connecting flange.

[0011] Preferably, both the inlet pressure switch and the outlet pressure switch are electronic pressure sensors, and the set pressure is 0.2-0.5 MPa.

[0012] Preferably, the temperature sensor is a PT100 temperature sensor.

[0013] Preferably, the atomizing reaction module is equipped with an atomizing nozzle with a spray angle of 55°-65°.

[0014] Preferably, it also includes a finished product collection module, which is connected to the material output end of the atomization reaction module.

[0015] Preferably, the system also includes a control system, which is electrically connected to the temperature control unit of the two-stage series heating module, the pressure switch of the pressure control module, and the temperature sensor. When the temperature sensor detects that the nitrogen temperature is below 490°C or above 510°C, the control system triggers an audible and visual alarm.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] 1. The device of this utility model adopts a two-stage series stepped heating method, which can control the temperature fluctuation of nitrogen within ±3℃, greatly improving the temperature stability compared with the traditional single-group heating, and ensuring a constant atomization temperature; it can also greatly shorten the nitrogen heating time, which is more energy-efficient than the traditional method and reduces production costs.

[0018] 2. The device of this utility model adopts a dual pressure switch to monitor the inlet and outlet pressure in real time. The pressure regulating valve responds quickly, the pressure control is precise, and the system pressure fluctuation is small, which can avoid powder defects caused by sudden pressure changes. The powder quality is optimized, the particle size deviation of the produced ultrafine alloy powder is small, the composition uniformity is improved, and it can be directly used for 3D printing and hot isostatic pressing. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] legend:

[0021] 1. Nitrogen supply module; 2. Primary heater; 3. Heating wire; 4. Pressure control module; 5. Connecting flange; 6. Secondary heater; 7. Temperature sensor; 8. Atomization reaction module. Detailed Implementation

[0022] The utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1 As shown, an embodiment of the two-stage series nitrogen heating and pressure control ultrafine alloy powder production device of this utility model includes a nitrogen supply module 1 (which is prior art). Figure 1 (Illustrated only by circles), heating module, pressure control module 4, and atomization reaction module 8 (existing technology). Figure 1 (Illustrated only by circles). The heating module is a two-stage series heating module, consisting of a primary heater 2 and a secondary heater 6 connected in series. The set heating temperature of the secondary heater 6 is higher than that of the primary heater 2. The input end of the primary heater 2 is connected to the output end of the nitrogen supply module 1 through an inlet pipe, and the output end of the secondary heater 6 is connected to the air inlet of the atomization reaction module 8 through an outlet pipe. A temperature sensor 7 (preferably a PT100 temperature sensor) is installed on the outlet pipe. The pressure control module 4 includes an inlet pressure switch, an outlet pressure switch, and an electronic pressure regulating valve. The inlet pressure switch and the electronic pressure regulating valve are both installed on the inlet pipe, and the outlet pressure switch is installed on the outlet pipe. The electronic pressure regulating valve is linked to the inlet pressure switch. When the pressure exceeds the set range, the electronic pressure regulating valve automatically adjusts the nitrogen input. This invention employs a two-stage series stepped heating method, which can shorten the nitrogen heating time, improve the nitrogen temperature stability, and ensure a constant atomization temperature. It is more energy-efficient and has lower production costs than traditional methods. The use of dual pressure switches enables real-time monitoring of the inlet and outlet pressures, ensuring precise pressure control and minimal system pressure fluctuations. This avoids powder defects caused by sudden pressure changes and improves powder quality.

[0024] In this embodiment, the set heating temperature of the primary heater 2 is 280-320℃, and the set heating temperature of the secondary heater 6 is 500℃.

[0025] In this embodiment, both the primary heater 2 and the secondary heater 6 are made of stainless steel, with an inner diameter of 50-60 mm. A heating wire 3 is installed inside the tube, and the inner wall is coated with a 0.15-0.2 mm thick high-temperature resistant insulating layer. The primary heater is 1.0-1.2 m long, and the secondary heater is 1.2-1.4 m long. The primary and secondary heaters are connected in series via high-temperature resistant piping and sealed using a connecting flange 5 (preferably a graphite sealing flange) to ensure airtightness at high temperatures.

[0026] Alternatively, the primary heater 2 and the secondary heater 6 are made of 310S stainless steel tubes with an inner diameter of 55mm, with a built-in Φ0.7mm nickel-chromium alloy heating wire 3, and the inner wall is coated with a 0.18mm Al2O3 coating. The length of the primary heater is 1.1m, and the length of the secondary heater is 1.3m.

[0027] In this embodiment, both the inlet pressure switch and the outlet pressure switch are electronic pressure sensors with a measurement range of 0-1 MPa, an accuracy of ±0.01 MPa, and a set pressure of 0.2-0.5 MPa. More preferably, the set pressure of the inlet pressure switch is 0.5 MPa, and the set pressure of the outlet pressure switch is 0.55 MPa. The electronic pressure regulating valve is a proportional electric valve with a response time ≤0.4 s.

[0028] In this embodiment, the atomization reaction module 8 is equipped with a stainless steel atomizing nozzle, and the spray angle of the atomizing nozzle is 55°-65° (preferably 60°). The inlet of the atomizing nozzle is connected to the outlet of the secondary heater 6 through a Φ70mm stainless steel pipe, and a PT100 temperature sensor (measuring range 0-800℃, accuracy ±0.5℃) is installed on the pipe.

[0029] In this embodiment, a finished product collection module is also included. The finished product collection module includes a cyclone separator, a bag filter and a finished product storage tank connected in sequence. The feed inlet of the cyclone separator is connected to the material output end of the atomization reaction module (the specific structure and connection relationship are all prior art and are not shown in the figure).

[0030] In this embodiment, a control system may also be included. The control system is electrically connected to the temperature control unit of the two-stage series heating module, the pressure switch of the pressure control module, and the temperature sensor (the connection relationships are all prior art and are not shown in the figure). When the temperature sensor detects that the nitrogen temperature is below 490°C or above 510°C, the control system triggers an audible and visual alarm and automatically adjusts the heating power of the secondary heater. If the temperature continues to exceed the threshold for more than 5 minutes, the output of the nitrogen supply module is cut off.

[0031] The following are specific examples of producing ultrafine high-temperature alloy powder (alloy powder 316) using the apparatus of this invention:

[0032] comprising the following steps:

[0033] Step 1: Perform air tightness test on the device, introduce nitrogen at 0.8MPa for pressure holding for 25min, and it is qualified when the pressure drop is ≤0.01MPa.

[0034] Step 2: Turn on the nitrogen supply module, set the inlet pressure switch to 0.5MPa and the outlet pressure switch to 0.55MPa through the control system, and start the primary heater (300℃) and the secondary heater (500℃).

[0035] Step 3: When the temperature sensor shows that the nitrogen temperature is stable at 495-505℃ and the outlet pressure switch shows that the pressure is stable at 0.55±0.02MPa, deliver the molten alloy raw material at 1550-1750℃ to the atomization reaction module at a rate of 4-6kg / h.

[0036] Step 4: High-temperature nitrogen at 500℃ is sprayed at a high speed (18-22m / s) through the gas atomizing nozzle (the nitrogen spraying pressure is consistent with the set pressure of the outlet pressure switch), so as to break the molten alloy stream into ultrafine droplets, and the droplets are cooled to room temperature in a nitrogen atmosphere to form ultrafine alloy powder.

[0037] Step 5: The ultrafine alloy powder is subjected to two-stage separation by the cyclone separator (separation efficiency ≥96%) and the bag filter (filtration accuracy 0.8μm) of the finished product collection module, and the finished product is collected, and the tail gas is discharged after impurity removal treatment.

[0038] The above are all preferred embodiments of the present application, which are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A two-stage series nitrogen heating and pressure control ultrafine alloy powder production device, comprising a nitrogen supply module (1), a heating module, a pressure control module (4), and an atomization reaction module (8), characterized in that, The heating module is a two-stage series heating module, including a primary heater (2) and a secondary heater (6) connected in series. The set heating temperature of the secondary heater (6) is higher than that of the primary heater (2). The input end of the primary heater (2) is connected to the output end of the nitrogen supply module (1) through the inlet pipe. The output end of the secondary heater (6) is connected to the air inlet of the atomization reaction module (8) through the outlet pipe. A temperature sensor (7) is provided on the outlet pipe. The pressure control module (4) includes an inlet pressure switch, an outlet pressure switch and an electronic pressure regulating valve. The inlet pressure switch and the electronic pressure regulating valve are both installed on the inlet pipe. The outlet pressure switch is installed on the outlet pipe. The electronic pressure regulating valve is linked with the inlet pressure switch. When the pressure exceeds the set range, the electronic pressure regulating valve automatically adjusts the nitrogen input.

2. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, The set heating temperature of the primary heater (2) is 280-320℃, and the set heating temperature of the secondary heater (6) is 500℃.

3. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, The tubes of the primary heater (2) and the secondary heater (6) are both made of stainless steel, with an inner diameter of 50-60 mm. A heating wire (3) is installed inside the tube, and the inner wall of the tube is coated with a high-temperature resistant insulation layer of 0.15-0.2 mm thickness. The length of the primary heater (2) is 1.0-1.2 m, and the length of the secondary heater (6) is 1.2-1.4 m.

4. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, The primary heater (2) and the secondary heater (6) are connected by a high-temperature resistant pipeline and sealed by a connecting flange (5).

5. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, Both the inlet pressure switch and the outlet pressure switch are electronic pressure sensors, and the set pressure is 0.2-0.5 MPa.

6. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, The temperature sensor (7) is a PT100 temperature sensor.

7. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, The atomizing reaction module (8) is equipped with an atomizing nozzle with a spray angle of 55°-65°.

8. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 1, characterized in that, It also includes a finished product collection module, the inlet of which is connected to the material output end of the atomizing reaction module (8).

9. The two-stage series nitrogen heating and pressure control ultrafine alloy powder production device according to claim 2, characterized in that, It also includes a control system, which is electrically connected to the temperature control unit of the two-stage series heating module, the pressure switch of the pressure control module (4), and the temperature sensor (7). When the temperature sensor (7) detects that the nitrogen temperature is below 490°C or above 510°C, the control system triggers an audible and visual alarm.

Images