AU2021107132A4

AU2021107132A4 - Vacuum sintering furnace

Info

Publication number: AU2021107132A4
Application number: AU2021107132A
Authority: AU
Inventors: Kejian Chen; Yingxin Li; Peiyu WANG; Junguang XIAO
Original assignee: Zhuzhou Ruideer Intelligent Thermal Equipment Co Ltd
Current assignee: Zhuzhou Ruideer Intelligent Thermal Equipment Co Ltd
Priority date: 2021-07-16
Filing date: 2021-08-25
Publication date: 2021-12-02
Anticipated expiration: 2029-08-25
Also published as: CN215766457U

Abstract

OF THE DISCLOSURE The present utility model discloses a vacuum sintering furnace, including a sintering furnace body, a preheating device, a vacuum device, a condensing device, and a controller. A furnace jacket and a heat insulation sleeve are arranged inside the sintering furnace body in sequence from outside to inside; a heat insulation cavity is arranged between the sintering furnace body and the furnace jacket; a heating chamber is arranged in the sintering region; the heating chamber includes a heater; the heater is arranged between the outer side shell and the closed box; the closed box can collect a sintered body inside in a closed state; the closed box is connected with the vacuum device through a vacuum pipe; the preheating device includes a hollow barrel body and a preheating water pipe arranged on the outer side of the barrel body; the condensing device is arranged on the vacuum pipe, and includes a condensing pipe; a cooling water pipe is arranged on the outer side of the condensing pipe; a water outlet of the cooling water pipe is connected with a water inlet of the preheating water pipe through a pipeline; and the vacuum device is connected with the controller. By the present utility model, paraffin discharged in the sintering process can be recycled in time and pollution to a product is avoided. - 1/2 DRAWINGS 100 19 -3 4 2 516 6 28 12 17 10 15 o 22-L' FIG.1

Description

- 1/2

DRAWINGS

100 19 -3

4 2 516 6 28

12 17

10 15 o 22-L'

FIG.1

VACUUM SINTERING FURNACE TECHNICAL FIELD

[01] The present utility model relates to the technical field of vacuum sintering equipment, and particularly relates to a vacuum sintering furnace.

BACKGROUNDART

[02] Metal powder injection molding is a current rapidly developing new molding technology, which has the advantage of being able to form small parts of any complex shape and having good density uniformity in each part of a product. A general process of this technology is to mix fine metal powder with a binder. An advanced injection is injected into a mold cavity with a part shape to form a blank, and then the binder is removed by firing, the blank becomes highly dense, forming a metal product. As general sintering equipment, the vacuum sintering furnace heats and sinters the blank in a vacuum environment. In this process, a large amount of paraffin and other polymer materials will inevitably be discharged, which will pollute the product and a vacuumizing device, thereby reducing the service life of the vacuum sintering furnace.

SUMMARY

[03] The present utility model aims to provide a vacuum sintering furnace to solve the problems in the existing art, and paraffin, etc. discharged in the sintering process can be recycled in time to avoid pollution to a product.

[04] In order to achieve the above purpose, the present utility model provides the following solution.

[05] The present utility model provides a vacuum sintering furnace, including a sintering furnace body, a preheating device, a vacuum device, a condensing device and a controller. A furnace jacket and a heat insulation sleeve are arranged inside the sintering furnace body in sequence from outside to inside; a heat insulation cavity is arranged between the sintering furnace body and the furnace jacket; two ends of the sintering furnace body are symmetrically provided with a front furnace door and a rear furnace door; the front furnace door is provided with a first heat insulation pad capable of extending and retracting axially; and the rear furnace door is provided with a second heat insulation pad capable of extending and retracting axially. When the first heat insulation pad and the second heat insulation pad are respectively squeezed at two ends of the heat insulation sleeve, a closed sintering region can be formed. A heating chamber is arranged in the sintering region. One side of the heating chamber is hinged with a feeding door. The heating chamber includes an outer side shell, a heater and a closed box. The heater is arranged between the outer side shell and the closed box. The closed box can collect a sintered body inside in a closed state. The closed box is also connected with the vacuum device through a vacuum pipe. The vacuum pipe includes a vacuum main pipe and a vacuum branch pipe. A control valve is connected between the vacuum main pipe and the vacuum branch pipe. The preheating device includes a hollow barrel body and a preheating water pipe arranged on the outer side of the barrel body. The condensing device is arranged on the vacuum pipe, and includes a condensing pipe. A cooling water pipe is arranged on the outer side of the condensing pipe. A water outlet of the cooling water pipe is connected with a water inlet of the preheating water pipe through a pipeline, and the vacuum device is connected with the controller. The heating chamber heats the sintered body collected in the closed box by means of driving a heater. Heat of the heater is also transmitted to the outer side shell. Therefore, the heating chamber releases heat to the sintering furnace body. In the present implementation mode, the sintered body uses a sintered material in which resin is mixed in metal powder or ceramic powder to form a binder. The heating chamber heats the sintered body to degrease or sinter the sintered body.

[06] Optionally, a coolant circulating port is arranged outside the sintering furnace body, and includes an inlet and an outlet which are fixedly disposed on the outer side of the sintering furnace body and respectively communicate with the heat insulation cavity; and the coolant circulating port is connected with an air pump capable of supplying a circulating coolant. The circulating coolant is fed into the heat isolation cavity to accelerate cooling of the sintering region and improve the working efficiency.

[07] Optionally, the heating device is also arranged on the outer side of the condensing pipe.

[08] Optionally, the bottom end of the condensing pipe is provided with a collecting tank, and one side of the collecting tank is provided with a discharging pipe.

[09] Optionally, the discharging pipe is provided with a control valve.

[10] Optionally, a temperature sensor is also arranged in the sintering furnace body, and is connected with the controller.

[11] Optionally, the preheating water pipe is spirally wound on the outer side of the barrel body of the preheating device.

[12] Optionally, the cooling water pipe is spirally wound on the outer side of the condensing pipe.

[13] Optionally, at least one layer of first graphite pad is arranged on the inner side of the first heat insulation pad; at least one layer of second graphite pad is arranged on the inner side of the second heat insulation pad; and the surfaces of the first graphite pad and the second graphite pad are respectively coated with boron nitride layers with a thickness of 0.3 to 0.8 mm.

[14] Optionally, the heat insulation sleeve, the first heat insulation pad and the second heat insulation pad are all made of carbon fiber.

[15] The present utility model achieves the following technical effects compared to the existing art.

[16] In the present utility model, the condensing device is arranged on the vacuum pipe. By means of the condensing device, paraffin steam generated in the sintering process can be cooled and solidified on the inner wall of the condensing pipe to prevent the paraffin from entering the vacuum device. The cooling water used in the cooling device enters the preheating water pipe of the preheating device through a pipeline after absorbing the heat, thereby recycling part of the heat energy and saving the energy. In addition, the heating device is arranged outside the condensing pipe; the bottom of the condensing pipe is also provided with the collecting tank. After the equipment runs for a period of time, a large amount of paraffin is condensed on the inner wall of the condensing pipe. The paraffin is melted through the heating device, flows into the collecting tank along the inner wall, and is discharged from the discharging pipe, so that the condensing pipe is cleaned, and the paraffin is recycled. The present utility model can recycle paraffin and part of the heat energy to reduce the energy consumption and reduce the production cost.

BRIEF DESCRIPTION OF THE DRAWINGS

[17] In order to describe the embodiments of the present utility model or the technical solutions in the existing art more clearly, drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the illustration below are merely some embodiments of the present utility model. Those ordinarily skilled in the art also can acquire other drawings according to the provided drawings without doing creative work.

[18] FIG. 1 is a schematic diagram of an overall structure of a vacuum sintering furnace of the present utility model; and

[19] FIG. 2 is a schematic structural diagram of a condensing device of a vacuum sintering furnace of the present utility model.

[20] 100: vacuum sintering furnace; 1: sintering furnace body; 2: preheating device; 3: vacuum device; 4: condensing device; 5: furnace jacket; 6: heat insulation sleeve; 7: front furnace door; 8: rear furnace door; 9: first heat insulation pad; 10: second heat insulation pad; 11: first cylinder; 12: second cylinder; 13: outer side shell; 14: heater; 15: closed box; 16: vacuum pipe; 17: barrel body; 18: preheating water pipe; 19: pipeline; 20: cooling water pipe; 21: inlet; 22: outlet; 23: heating device; 24: collecting tank; 25: discharging pipe; and 26: control valve.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[21] The technical solutions in the embodiments of the present utility model will be described clearly and completely below with reference to the drawings in the embodiments of the present utility model. Obviously, the embodiments described herein are only part of the embodiments of the present utility model, not all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure.

[22] The present utility model aims to provide a vacuum sintering furnace to solve the problems in the existing art, and paraffin, etc. discharged in the sintering process can be recycled in time to avoid pollution to a product.

[23] In order to make the above-mentioned purposes, features and advantages of the present utility model more obvious and understandable, the present utility model is further described in detail below with reference to the accompanying drawings and specific implementation modes.

[24] Referring to FIG. 1 to FIG. 2, the present utility model provides a vacuum sintering furnace 100, including a sintering furnace body 1, a preheating device 2, a vacuum device 3, a condensing device 4, and a controller. A furnace jacket 5 and a heat insulation sleeve 6 are arranged inside the sintering furnace body 1 from outside to inside. A heat insulation cavity is formed between the sintering furnace body 1 and the furnace jacket 5. Two ends of the sintering furnace body 1 are symmetrically provided with a front furnace door 7 and a rear furnace door 8; the front furnace door 7 is provided with a first heat insulation pad 9 capable of extending and retracting axially; and the rear furnace door 8 is provided with a second heat insulation pad 10 capable of extending and retracting axially. When the first heat insulation pad 9 and the second heat insulation pad 10 are respectively squeezed at two ends of the heat insulation sleeve 6, a closed sintering region can be formed. The axial extension and retraction of the first heat insulation pad 9 and the second heat insulation pad 10 are respectively controlled by a first cylinder 11 and a second cylinder 12 which are arranged on the front furnace door 7 and the rear furnace door 8. A heating chamber is arranged in the sintering region. One side of the heating chamber is hinged with a feeding door. After the feeding door is closed, the inside of the heating chamber is closed. The heating chamber includes an outer side shell 13, a heater 14 and a closed box 15. The feeding door is hinged to one side of the closed box 15. An opening and closing door is arranged at a position on the outer side shell 13 corresponding to the feeding door. The heater 14 is arranged between the outer side shell 13 and the closed box 15. The closed box 15 can collect a sintered body inside in a closed state. The outer side shell 13 is arranged in the sintering region through a supporting frame. The closed box 15 is also connected with the vacuum device 3 through a vacuum pipe 16. The preheating device 2 includes a hollow barrel body 17 and a preheating water pipe 18 arranged on the outer side of the barrel body 17. The condensing device 4 is arranged on the vacuum pipe 16, and includes a condensing pipe. A cooling water pipe 20 is arranged on the outer side of the condensing pipe. A water outlet of the cooling water pipe 20 is connected with a water inlet of the preheating water pipe 18 through a pipeline 19, and the vacuum device 3 is connected with the controller. The heating chamber heats the sintered body collected in the closed box 15 by means of driving the heater 14. Heat of the heater 14 is also transmitted to the outer side shell 13. Therefore, the heating chamber releases heat to the sintering furnace body 1. In the present implementation mode, the sintered body uses a sintered material in which resin is mixed in metal powder or ceramic powder to form a binder. A coolant circulating port is arranged outside the sintering furnace body 1, and includes an inlet 21 and an outlet 22 which are fixedly disposed on the outer side of the sintering furnace body 1 and respectively communicate with the heat insulation cavity; and valves are respectively arranged on the inlet 21 and the outlet 22.

[25] Further preferably, a heating device 23 is also arranged on the outer side of the condensing pipe. A collecting tank 24 is arranged on the inner side of an opening in the bottom end of the condensing pipe, and one side of the collecting tank 24 is provided with a discharging pipe 25. A control valve 26 is arranged on the discharging pipe 25. A temperature sensor is also arranged in the sintering furnace body 1, and is connected with the controller. The preheating water pipe 18 is spirally wound on the outer side of the barrel body 17 of the preheating device 2. The cooling water pipe 20 is spirally wound on the outer side of the condensing pipe. At least one layer of first graphite pad is arranged on the inner side of the first heat insulation pad 9; at least one layer of second graphite pad is arranged on the inner side of the second heat insulation pad 10; and the surfaces of the first graphite pad and the second graphite pad are respectively coated with boron nitride layers with a thickness of 0.3 to 0.8 mm. The heat insulation sleeve 6, the first heat insulation pad 9 and the second heat insulation pad 10 are all made of carbon fiber.

[26] During working, the front furnace door 7 and the rear furnace door 8 are opened, and the sintered body is placed in the heating chamber on the supporting frame. The front furnace door 7 and the rear furnace door 8 are closed. At this time, the sintering region communicates with the heat insulation cavity. The first cylinder 11 and the second cylinder 12 are adjusted, so that the first heat insulation pad 9 and the second heat insulation pad 10 drive the first graphite pad and the second graphite pad to squeeze the heat insulation sleeve 6 and the graphite sleeve from both ends to form a closed sintering region. The heating chamber heats the sintered body to degrease or sinter the sintered body. The heating chamber heats a temperature region that gasifies or melts resin included in the sintered body during degreasing. During degreasing, the heating chamber enables inert gas (carrier gas), reducing gas or oxidizing gas to flow into the closed box 15 at stipulated flow, so that the internal pressure of the closed box 15 is in a pressure-reduced state. In addition, the heating chamber heats a temperature region that sinters the degreased sintered body during sintering. During sintering, the heating chamber enables inert gas (carrier gas), reducing gas or oxidizing gas to flow into the closed box 15 at stipulated flow, so that the internal pressure is in a pressure-reduced or normal pressure state. The vacuum pipe 16 discharges internal atmosphere (exhaust gas) of the heating chamber to the vacuum device 3 on the outer side.

[27] In the description of the present disclosure, it should be noted that orientations or positional relationships indicated by the terms "center", "top", "bottom", "left", "right", "vertical", "horizontal", "inside", "outside" and the like are orientations or positional relationships as shown in the drawings, and are only for the purpose of facilitating and simplifying the description of the present utility model instead of indicating or implying that devices or elements indicated must have particular orientations, and be constructed and operated in the particular orientations, so that these terms are not construed as limiting the present utility model. In addition, the terms "first" and "second" are only for the purpose of description, and may not be understood as indicating or implying the relative importance.

[28] The principle and implementation modes of the present utility model are described by applying specific examples in the present utility model. The descriptions of the above embodiments are only intended to help to understand the method of the present utility model and a core idea of the method. In addition, those ordinarily skilled in the art can make changes to the specific implementation modes and the application scope according to the idea of the present utility model. From the above, the contents of the present specification shall not be deemed as limitations to the present utility model.

Claims

WHAT IS CLAIMED IS:

1. A vacuum sintering furnace, comprising a sintering furnace body, a preheating device, a vacuum device, a condensing device and a controller, wherein a furnace jacket and a heat insulation sleeve are arranged inside the sintering furnace body in sequence from outside to inside; a heat insulation cavity is arranged between the sintering furnace body and the furnace jacket; two ends of the sintering furnace body are symmetrically provided with a front furnace door and a rear furnace door; the front furnace door is provided with a first heat insulation pad capable of extending and retracting axially; and the rear furnace door is provided with a second heat insulation pad capable of extending and retracting axially; when the first heat insulation pad and the second heat insulation pad respectively squeezes two ends of the heat insulation sleeve, a closed sintering region can be formed; a heating chamber is arranged in the sintering region; one side of the heating chamber is hinged with a feeding door; the heating chamber comprises an outer side shell, a heater and a closed box; the heater is arranged between the outer side shell and the closed box; the closed box is capable of collecting a sintered body inside in a closed state; the closed box is also connected with the vacuum device through a vacuum pipe; the preheating device comprises a hollow barrel body and a preheating water pipe arranged on the outer side of the barrel body; the condensing device is arranged on the vacuum pipe, and comprises a condensing pipe; a cooling water pipe is arranged on the outer side of the condensing pipe; a water outlet of the cooling water pipe is connected with a water inlet of the preheating water pipe, and the vacuum device is connected with the controller.

2. The vacuum sintering furnace according to claim 1, wherein the heating device is also arranged on the outer side of the condensing pipe; wherein the bottom end of the condensing pipe is provided with a collecting tank, and one side of the collecting tank is provided with a discharging pipe; wherein the discharging pipe is provided with a control valve.

3. The vacuum sintering furnace according to claim 1, wherein a temperature sensor is also arranged in the sintering furnace body, and is connected with the controller; wherein the preheating water pipe is spirally wound on the outer side of the barrel body of the preheating device; wherein the cooling water pipe is spirally wound on the outer side of the condensing pipe.

4. The vacuum sintering furnace according to claim 1, wherein at least one layer of first graphite pad is arranged on the inner side of the first heat insulation pad; at least one layer of second graphite pad is arranged on the inner side of the second heat insulation pad; and the surfaces of the first graphite pad and the second graphite pad are respectively coated with boron nitride layers with a thickness of 0.3 to 0.8 mm; wherein the heat insulation sleeve, the first heat insulation pad and the second heat insulation pad are all made of carbon fiber.

5. The vacuum sintering furnace according to claim 1, wherein a coolant circulating port is arranged outside the sintering furnace body, and comprises an inlet and an outlet which are fixedly disposed on the outer side of the sintering furnace body and respectively communicate with the heat insulation cavity; and the coolant circulating port is connected with an air pump capable of supplying a circulating coolant.