Hearth heating system of MIM sintering furnace

Abstract

The utility model discloses a hearth heating system of an MIM sintering furnace, which comprises a sintering furnace body, a nitrogen pipe and a vacuumizing pipe, the sintering furnace body is provided with a split furnace door, the top in the sintering furnace body is rotatably provided with a rotating disc, the top of the sintering furnace body is provided with a driving mechanism which is rotatably connected with the rotating disc, and the driving mechanism is connected with the nitrogen pipe. A supporting frame is vertically installed at the bottom of the rotating disc, a plurality of layers of containing discs are installed on the supporting frame from top to bottom at equal intervals, 3-4 storage grooves are evenly machined in the circumference of each layer of containing disc, a sintering jig is movably placed in each storage groove, and a heating cylinder is vertically arranged on the inner side of the supporting frame. A plurality of strip-shaped heating plates are evenly distributed on the outer wall of the heating cylinder in the circumferential direction, and a plurality of annular heating plates are installed on the inner wall of the heating furnace body at intervals in the vertical direction. According to the system, the MIM product can be uniformly heated, the sintering quality is improved, the heating speed is high, the heating efficiency is high, and the sintering efficiency can be greatly improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of powder metallurgy injection molding process, and in particular relates to a furnace heating system of a MIM sintering furnace. Background Art

[0002] Metal Injection Molding, referred to as MIM, is a process of selecting metal powder and binder that meet the requirements of MIM, and then mixing the powder and binder into a uniform feed at a certain temperature using an appropriate method. After granulation, the obtained molded blank is degreased and sintered to become the final product. Sintering is the last step in the MIM process. Sintering eliminates the pores between powder particles. The MIM product is fully dense or nearly fully dense. The MIM sintering furnace refers to a furnace that performs protective sintering on MIM products in a vacuum environment. There are many heating methods, such as resistance heating,

[0003] Induction heating, microwave heating, etc., the vacuum is mainly to extract the internal air through a vacuum pump, and then fill it with nitrogen.

[0004] Protection, the existing sintering furnace has the following shortcomings during use: First, the existing sintering furnace only relies on the electric heating wire arranged on the furnace wall to heat it, and its heating speed is slow and the heating efficiency is high; second, the existing sintering furnace is a multi-layer fixed structure, and the sintering fixture is fixed on the shelf for static heating. This static heating method has the phenomenon of uneven sintering of MIM products, which not only affects the sintering quality of MIM products, but also affects the sintering efficiency. Therefore, it is an objective need to develop a furnace heating system for MIM sintering furnaces that is easy to implement, heats more evenly, and has higher heating efficiency. Summary of the invention

[0005] The utility model aims to provide a furnace heating system for a MIM sintering furnace which is easy to implement, has more uniform heating and higher heating efficiency.

[0006] The purpose of the utility model is achieved in this way, including a sintering furnace body, a nitrogen pipe and a vacuum pipe, the sintering furnace body is provided with a double-opening furnace door, a rotating disk is rotatably installed on the top of the sintering furnace body, a driving mechanism rotatably connected to the rotating disk is installed on the top of the sintering furnace body, a support frame is vertically installed at the bottom of the rotating disk, a plurality of layers of placement disks are installed on the support frame at equal intervals from top to bottom, each layer of placement disks is evenly processed with 3 to 4 placement grooves on the circumference, a sintering fixture adapted thereto is movably placed in each placement groove, a heating cylinder is vertically arranged on the inner side of the support frame, the bottom of the heating cylinder is fixedly connected to the bottom of the sintering furnace body, a sealing plate is installed on the top of the heating cylinder, a plurality of strip heating plates are evenly arranged on the circumference of the outer wall of the heating cylinder, the strip heating plates are arranged along the axial direction of the heating cylinder, and a plurality of annular heating plates are installed on the inner wall of the sintering furnace body at intervals up and down along its vertical direction.

[0007] Compared with the existing technology, the advantages of the device are: first, the placement structure of the sintering jig is optimized, the sintering jig is placed on the placement plate in layers, and then the driving structure is used to drive the support frame and the placement plate to rotate synchronously, and the MIM product in the sintering jig is heated and sintered in a rotating manner, which can solve the problem of uneven sintering and make the area of ​​the MIM product in the sintering jig in contact with heat more uniform, which is beneficial to improving the sintering quality of the MIM product and further improving the qualified rate of the MIM product; second, the device is provided with corresponding annular heating plates and strip heating plates on the inner wall and center of the heating furnace body, and the rotating placement plate is heated inside and outside by the annular heating plates and strip heating plates. The heating speed of the internal and external heating is higher, the heating efficiency is better, and the MIM product can be heated uniformly in all directions, and the sintering effect of the MIM product is better. The device has the advantages of reasonable structure, easy implementation, more uniform heating, and better sintering effect, and is easy to promote and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a main schematic diagram of the utility model;

[0009] Figure 2 for Figure 1 BB view in;

[0010] Figure 3 for Figure 1 A magnified schematic diagram of part A;

[0011] In the figure: 1-sintering furnace body, 2-nitrogen pipe, 3-vacuum pipe, 4-opening furnace door, 5-rotating plate, 6-support frame, 7-placing plate, 71-storage slot, 8-sintering fixture, 9-heating cylinder, 10-strip heating plate, 11-driving motor, 12-rotating shaft, 13-magnet block, 14-annular heating plate, 15-annular base, 16-annular slide rail, 17-exhaust box, 18-exhaust channel, 19-exhaust pipe, 20-baffle, 21-circulation pipe. DETAILED DESCRIPTION

[0012] The present invention is further described below in conjunction with the accompanying drawings, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention belong to the protection scope of the present invention.

[0013] like Figures 1 to 3 As shown, the utility model includes a sintering furnace body 1, a nitrogen pipe 2 and a vacuum pipe 3. The sintering furnace body 1 is provided with a split furnace door 4. The split furnace door 4 is designed to facilitate the removal and placement of a sintering fixture 8. A rotating disk 5 is rotatably installed on the top of the sintering furnace body 1. A driving mechanism rotatably connected to the rotating disk 5 is installed on the top of the sintering furnace body 1. A support frame 6 is vertically installed at the bottom of the rotating disk 5. Multiple layers of placement disks 7 are installed on the support frame 6 at equal intervals from top to bottom. Each layer of the placement disk 7 is evenly processed with 3 to 4 placement grooves 71 on the circumference. Each placement groove 71 has a plurality of storage slots 71. A sintering fixture 8 adapted thereto is movably placed, and a plurality of MIM product placement slots are placed on the sintering fixture 8, and the MIM products are placed in the MIM product placement slots. A heating cylinder 9 is vertically arranged on the inner side of the support frame 6, and the bottom of the heating cylinder 9 is fixedly connected to the bottom of the sintering furnace body 1, and a sealing plate is installed on the top of the heating cylinder 9. A plurality of strip heating plates 10 are evenly distributed on the circumference of the outer wall of the heating cylinder 9, and the strip heating plates 10 are arranged along the axial direction of the heating cylinder 9. A plurality of annular heating plates 14 are installed on the inner wall of the sintering furnace body 1 at intervals in the vertical direction thereof.

[0014] The method of using the device to sinter MIM products is as follows: when using, first open the split furnace door 1, and place the sintering jig 8 containing the MIM product on each layer of the placing plate 7 in turn. After the sintering jig 8 is placed, close the split furnace door 1, and then connect the strip heating plate 10 and the annular heating plate 14 to the external power supply, and then connect the vacuum tube 3 to the external vacuum pump, and connect the nitrogen tube 2 to the nitrogen source, first use the vacuum pump to extract the air inside the sintering furnace body 1 to form a vacuum, and then fill the inside of the sintering furnace body 1 with nitrogen through the nitrogen tube 2. Nitrogen is introduced for protection, and then the strip heating plate 10 and the annular heating plate 14 are powered on for heating. At the same time, the driving mechanism drives the support frame 6 and the placement plate 7 to rotate, and the heat generated by the strip heating plate 10 is transferred outwardly, and the heat generated by the annular heating plate 14 is transferred inwardly. The heat transferred inwardly and the heat transferred inwardly heat the sintering fixture 8 on the placement plate 7 inside and outside at the same time, which can not only achieve uniform heating of the MIM product and improve the quality of sintering, but also have a fast heating speed and high heating efficiency, which can greatly improve the sintering efficiency.

[0015] Furthermore, the driving mechanism includes a driving motor 11 and a rotating shaft 12. The driving motor 11 is a structure used in the prior art, and the finished product can be directly purchased according to the power size used. The rotating shaft 12 is rotatably installed on the top of the sintering furnace body 1, and the lower end of the rotating shaft 12 is fixedly connected to the top of the rotating disk 5. The upper end of the rotating shaft 12 is drivingly connected to the output shaft of the driving motor 11. When in use, the driving motor 11 drives the rotating shaft 12 to rotate, and the rotating shaft 12 can drive the rotating disk 5 to rotate, thereby driving the support frame 6 and the multi-layer placement disk 7 to rotate synchronously.

[0016] Furthermore, in order to fully utilize the space of the placement tray 7, a sufficient number of sintering jigs 8 are placed on each layer of the placement tray 7. The placement groove 71 is a fan-shaped structure. In order to further improve the heating effect, a plurality of heating holes are machined through the bottom of the placement groove 71. The heat generated by the strip heating plate 10 and the annular heating plate 14 can directly contact the sintering jig 8 through the heating holes, which can further improve the heating effect.

[0017] Furthermore, the support frame 6 includes multiple support cylinder sections connected to the placement plate 7, and the upper and lower adjacent support cylinder sections are connected and fixed by multiple support rods. This structure can not only achieve fixed connection of the multi-layer placement plate 7, but also enable the heat generated by the heating plate to pass through the connected upper and lower support cylinder sections, which is beneficial to improving the heating effect.

[0018] Furthermore, a magnet block 13 that attracts each other is provided between the sintering jig 8 and the storage tank 71. The magnet block 13 is used to fix the sintering jig 8 in the storage tank 71. The installation is convenient and the connection is firm, which can ensure that the sintering jig 8 is not easy to fall out of the storage tank 71 during rotation.

[0019] Further, preferably, the strip heating plate 10 comprises a heating shell and an electric heating net installed in the heating shell, wherein the electric heating net is composed of a plurality of electric heating wires, and the electric heating net is distributed in the heating shell, and the heating speed thereof is fast, and a good heating effect can be achieved. The structure of the annular heating plate 14 is the same as that of the strip heating plate 10.

[0020] Furthermore, in order to ensure the smooth operation of the rotating disk 5 during the rotation process, an annular base 15 is installed on the top of the sintering furnace body 1, and an annular groove is processed on the bottom of the annular base 15. An annular slide rail 16 matching the annular groove is installed on the top surface of the rotating disk 5, and a plurality of balls are installed on the top of the annular slide rail 16. The annular slide rail 16 is slidably installed in the annular groove. In the process of the driving mechanism driving the rotating disk 5 to rotate, the annular slide rail 16 on the rotating disk 5 can run smoothly in the annular groove, thereby ensuring the stability of the placement disk 7 during rotation.

[0021] Furthermore, in order to realize energy-saving and efficient production of the sintering furnace body 1, an exhaust assembly is provided on one side of the sintering furnace body 1, and the exhaust assembly includes an exhaust box 17 provided on one side of the sintering furnace body 1, and an exhaust channel 18 connected to the exhaust box 17 is provided on the upper part of the sintering furnace body 1, and an exhaust pipe 19 is installed on the top of the exhaust box 17. A plurality of baffles 20 are staggeredly installed up and down inside the exhaust box 17, and a circulation pipe 21 connected to the heating cylinder 9 is installed at the bottom of the exhaust box 17. Control valves are installed on the exhaust pipe 19 and the circulation pipe 21. When in use, the control valve on the exhaust pipe 19 is closed. By opening the control valve on the circulation pipe 21, the hot air in the sintering furnace body 1 will enter the exhaust box 17 through the exhaust channel 18. The hot air entering the exhaust box 17 will flow in an S shape in the exhaust box after being baffled by the baffle plate 20, and then flow into the sintering furnace body 1 through the circulation pipe 21. The hot air circulation flow is used for heating, which can save more electric energy and achieve the effect of energy saving and high efficiency. When the sintering task in the sintering furnace body 1 is completed, the control valve on the exhaust pipe 19 is opened, and the control valve on the circulation pipe 21 is closed. The hot air is discharged through the exhaust pipe 19 and enters the subsequent exhaust gas purification system.

Claims

1. A furnace heating system for a MIM sintering furnace, comprising a sintering furnace body (1), a nitrogen pipe (2) and a vacuum pipe (3), characterized in that The sintering furnace body (1) is provided with a double-opening furnace door (4), a rotating disk (5) is rotatably installed on the top of the sintering furnace body (1), a driving mechanism rotatably connected to the rotating disk (5) is installed on the top of the sintering furnace body (1), a support frame (6) is vertically installed on the bottom of the rotating disk (5), and multiple layers of placement disks (7) are installed on the support frame (6) at equal intervals from top to bottom, and each layer of the placement disk (7) is evenly distributed on the circumference and processed with 3 to 4 placement grooves (71), and each placement groove (71) is movably placed with a A sintering fixture (8) adapted thereto is provided, a heating cylinder (9) is vertically arranged on the inner side of the support frame (6), the bottom of the heating cylinder (9) is fixedly connected to the bottom of the sintering furnace body (1), a sealing plate is installed on the top of the heating cylinder (9), a plurality of strip heating plates (10) are evenly distributed on the circumference of the outer wall of the heating cylinder (9), the strip heating plates (10) are arranged along the axial direction of the heating cylinder (9), and a plurality of annular heating plates (14) are installed on the inner wall of the sintering furnace body (1) at intervals in the vertical direction thereof.

2. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: The driving mechanism comprises a driving motor (11) and a rotating shaft (12); the rotating shaft (12) is rotatably mounted on the top of the sintering furnace body (1); the lower end of the rotating shaft (12) is fixedly connected to the top of the rotating disk (5); and the upper end of the rotating shaft (12) is drivingly connected to the output shaft of the driving motor (11).

3. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: The storage groove (71) is a fan-shaped structure, and a plurality of heating holes are machined through the bottom of the storage groove (71).

4. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: The support frame (6) comprises a plurality of support tube sections connected to the placement plate (7), and two upper and lower adjacent support tube sections are connected and fixed via a plurality of support rods.

5. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: A magnet block (13) that attracts each other is provided between the sintering jig (8) and the storage groove (71).

6. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: The strip heating plate (10) comprises a heating shell and an electric heating net installed in the heating shell, the electric heating net is composed of a plurality of electric heating wires, and the structure of the annular heating plate (14) is the same as that of the strip heating plate (10).

7. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: An annular base (15) is installed at the top of the sintering furnace body (1), and an annular groove is processed on the bottom of the annular base (15). An annular slide rail (16) matching the annular groove is installed on the top surface of the rotating disk (5), and a plurality of ball bearings are installed on the top of the annular slide rail (16). The annular slide rail (16) is slidably installed in the annular groove.

8. The furnace heating system of a MIM sintering furnace according to claim 1, characterized in that: An exhaust assembly is arranged on one side of the sintering furnace body (1), and the exhaust assembly comprises an exhaust box (17) arranged on one side of the sintering furnace body (1); an exhaust passage (18) connected to the exhaust box (17) is arranged on the upper part of the sintering furnace body (1); an exhaust pipe (19) is installed on the top of the exhaust box (17); a plurality of baffles (20) are installed in an upper and lower staggered manner inside the exhaust box (17); a circulation pipe (21) connected to the heating cylinder (9) is installed at the bottom of the exhaust box (17); and control valves are installed on both the exhaust pipe (19) and the circulation pipe (21).

Images