CN114322566A - High temperature vacuum graphite sintering furnace - Google Patents

Abstract

The invention provides a high-temperature vacuum graphite sintering furnace, and belongs to the technical field of vacuum sintering equipment. This temperature vacuum graphite fritting furnace includes a furnace section of thick bamboo and sets up the bell at a furnace section of thick bamboo both ends, be provided with the heat shield main part in the furnace section of thick bamboo, the bell inboard is provided with heat shield end cover subassembly, heat shield end cover subassembly includes preceding screen, slide rail and driving piece, the slide rail is fixed to be set up on the furnace cover, preceding screen slides and sets up on the slide rail, the screen before the output of driving piece is connected, when the bell lid fits a furnace section of thick bamboo, the driving piece can drive the lid fit the preceding screen and the separation of heat shield main part of the tip of heat shield main part. After the sintering is accomplished, naturally cool down to suitable temperature after, the driving piece is shielded forward and is applyed a power of keeping away from the tip of heat shield main part for preceding shield and heat shield main part separation form the gas exchange passageway, accelerate the cooling rate in the soaking zone in the heat shield, thereby be favorable to shortening the cooling time, accelerate cooling rate.

Description

High temperature vacuum graphite sintering furnace

technical field

The invention belongs to the technical field of vacuum sintering equipment, and particularly relates to a high-temperature vacuum graphite sintering furnace.

Background technique

Vacuum graphite sintering furnace refers to the equipment that realizes high temperature or ultra-high temperature (temperature above 2600 ℃) sintering of cemented carbide cutter heads and various metal powder compacts under vacuum environment or protective atmosphere conditions. Its main components include electric furnace body. , vacuum system, water cooling system, etc. For example, the Chinese invention patent with the patent number of 201911388388.6 discloses a heat shield isolation ultra-high temperature vacuum sintering furnace, which includes a furnace tube and a heater, a heat shield, a cooling member and an isolation member arranged in the furnace tube.

In the prior art, in order to facilitate operation and better heat insulation, both ends of the heat shield are fixed on the furnace cover of the furnace drum. hot cavity. However, the actual working temperature of the vacuum sintering furnace exceeds 2000 °C, and can even reach 2600 °C. After the sintering is completed, it needs to be naturally cooled to about 600 °C, and then continue to cool down through the internal gas phase circulation. During the cooling process, under the barrier of the heat shield, the cooling rate inside the thermal insulation chamber is slow, and the entire cooling cycle needs to last 3-4 days.

SUMMARY OF THE INVENTION

Based on this, the present invention provides a high-temperature vacuum graphite sintering furnace to solve the technical problem of the slow cooling rate of the vacuum sintering furnace in the prior art.

A high-temperature vacuum graphite sintering furnace, comprising a furnace barrel and a furnace cover arranged at both ends of the furnace barrel, a heat shield main body is arranged in the furnace barrel, a heat shield end cover assembly is arranged inside the furnace cover, and the heat shield is provided inside the furnace cover. The screen end cover assembly includes a front screen, a sliding rail and a driving member, the sliding rail is fixedly arranged on the furnace cover, the front screen is slidably arranged on the sliding rail, and the output end of the driving member is connected to the For the front screen, when the furnace cover is covered with the furnace drum, the driving member can drive the front screen covered with the end of the heat screen main body to separate from the heat screen main body.

Preferably, the sliding rails are arranged along a cross-sectional direction perpendicular to the furnace cover, and sliding ears are provided on the sides of the front screen, the sliding ears are slidably installed on the sliding rails, and the driving members are arranged on the the rear end of the front screen to pull the front screen to slide along the slide rail.

Preferably, a circulating cooling chamber is formed between the heat shield main body and the furnace drum, and a separator is arranged in the middle of the circulating cooling chamber, and the separator divides the circulating cooling chamber into an air inlet chamber and an air outlet chamber The high temperature vacuum graphite sintering furnace also includes a cooling circulation fan, the inlet end of the cooling circulation fan is provided with a circulation inlet pipe, the outlet end is provided with a circulation outlet pipe, the circulation inlet pipe is connected to the air outlet cavity, and the circulation The outlet pipe communicates with the intake cavity.

Preferably, a cooling jacket is provided on the outer side of the circulation inlet pipe and/or the circulation outlet pipe, and a cooling medium can be introduced into the cooling jacket.

Preferably, the cooling jacket is arranged in sections.

Preferably, a first shut-off valve is arranged on the circulation inlet pipe or the circulation outlet pipe, a connecting pipe is arranged in front of the valve of the first shut-off valve, and a second shut-off valve is arranged on the connecting pipe; the connection The other end of the pipe is connected with a Roots blower.

Preferably, the inlet end of the Roots blower communicates with the heat shield body.

Preferably, the other end of the connecting pipe is located in front of the Roots blower, and is further provided with a dewaxing device; the inlet end of the dewaxing device is connected to the connecting pipe, and the outlet end is connected to the Roots blower. Entrance.

Preferably, the cooling circulating fan includes a motor, a radiator, and a water-cooling cavity disposed at the inlet end of the radiator, and a water-cooling coil is disposed in or around the water-cooling cavity.

Preferably, the driving member can drive the front screen to move linearly by 1 cm-5 cm.

Compared with the prior art, the present invention has at least the following advantages:

A heat shield end cover assembly including a front screen, a sliding rail and a driving member is arranged on the furnace cover. When the furnace cover is closed on the furnace drum, the driving member can drive the cover to be closed on the heat shield. The front screen at the end of the main body is separated from the heat screen main body. During high temperature sintering, the driving member applies a force to the front screen close to the end of the heat screen main body, so as to improve the sealing performance between the front screen and the heat screen main body. After the sintering is completed, after the temperature is naturally cooled to a suitable temperature, the driving member applies a force to the front screen away from the end of the heat screen body, so that the front screen is separated from the heat screen body and forms gas. Exchange channels to accelerate the cooling rate of the soaking zone in the heat shield, which is beneficial to shorten the cooling time and speed up the cooling rate.

Description of drawings

FIG. 1 is a front view of a high temperature vacuum graphite sintering furnace according to an embodiment.

2 is a schematic cross-sectional view of a high temperature vacuum graphite sintering furnace according to an embodiment.

3 is a schematic cross-sectional view of a high temperature vacuum graphite sintering furnace according to an embodiment.

FIG. 4 is a schematic diagram of a working state of a high temperature vacuum graphite sintering furnace according to an embodiment.

In the figure: high temperature vacuum graphite sintering furnace 10, furnace barrel 100, furnace cover 200, heat shield body 300, heat shield end cover assembly 400, front shield 410, sliding lugs 411, slide rails 420, driving parts 430, circulating cooling chamber 500 , air inlet chamber 510, air outlet chamber 520, baffle 600, cooling circulating fan 700, motor 701, radiator 702, water cooling chamber 703, water cooling coil 704, circulation inlet pipe fitting 710, circulation outlet pipe fitting 720, cooling jacket 730, The first shut-off valve 740 , the connecting pipe 750 , the second shut-off valve 760 , the roots blower 770 , and the dewaxing device 780 .

Detailed ways

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict. The technical solutions of the present invention will be further described below with reference to the accompanying drawings of the embodiments of the present invention, and the present invention is not limited to the following specific embodiments.

It should be understood that the same or similar reference numerals correspond to the same or similar components in the drawings of the embodiments. In the description of the present invention, it should be understood that if the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom" and the like indicate the orientation Or the positional relationship is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the accompanying drawings are only used for exemplary illustration, and should not be construed as a limitation on the present patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

Referring to FIGS. 1 to 3 , in one embodiment, a high-temperature vacuum graphite sintering furnace 10 includes a furnace barrel 100 and a furnace cover 200 disposed at both ends of the furnace barrel 100 . The furnace barrel 200 is provided with a heat The screen main body 300, the inner side of the furnace cover 200 is provided with a heat screen end cover assembly 400, the heat screen end cover assembly 400 includes a front screen 410, a sliding rail 420 and a driving member 430, and the sliding rail 420 is fixedly arranged on the On the furnace cover 200 , the front screen 410 is slidably arranged on the sliding rail 420 , and the output end of the driving member 430 is connected to the front screen 410 . When the furnace cover 200 is covered with the furnace drum 100 , the driving member 430 can drive the front screen 410 covering the end of the heat shield body 300 to separate from the heat shield body 300 .

Specifically, the furnace cover 200 can be covered on both sides of the furnace drum 100 to form a closed sintering space. The heat shield body 300 is disposed in the furnace barrel 100 , a soaking zone for high temperature sintering is formed inside the heat shield body 300 , and a soaking zone is formed between the heat shield body 300 and the furnace barrel 100 . The low temperature area (hereinafter referred to as the circulating cooling chamber 500 ). Generally, when the furnace cover 200 is covered with the furnace drum 100 , the front screen 410 is covered with the end of the heat shield body 300 to ensure the airtightness of the heat shield body 300 . In the present invention, a heat shield end cover assembly 400 including the front screen 410 , the slide rail 420 and the driving member 430 is arranged on the furnace cover 200 . During high temperature sintering, the driving member 430 moves toward the The front screen 410 exerts a force close to the end of the heat shield body 300 to improve the sealing performance between the front screen 410 and the heat shield body 300 . After the sintering is completed, the temperature is naturally cooled to a suitable temperature (generally, in order to prevent the high temperature gas from damaging the external pipe fittings, the temperature of the soaking zone is lowered to below 600°C, and then the gas circulation is turned on to cool down), the driving member 430 turns to the temperature. The front screen 410 exerts a force away from the end of the heat shield body 300 , so that the front screen 410 is separated from the heat shield body 300 , forming a gas exchange channel and accelerating the heat soaking zone in the heat shield body 300 . The cooling rate is beneficial to shorten the cooling time and speed up the cooling rate. Practice shows that when only the heat shield end cover assembly 400 is provided, the cooling cycle of the high temperature vacuum graphite sintering furnace 10 is shortened to within 72 hours.

For example, the sliding rails 420 are arranged along a cross-sectional direction perpendicular to the furnace cover 200 , and sliding ears 411 are arranged on the side of the front screen 410 , and the sliding ears 411 are slidably installed on the sliding rails 420 . The driving member 430 is disposed at the rear end of the front screen 410 to pull the front screen 410 to slide along the sliding rail 420 . On the one hand, the sliding rail 420 supports the front screen 410 and keeps the front screen coaxial with the heat screen main body 300 , and on the other hand guides the front screen 410 along the The slide rail 420 slides.

Preferably, the driving member 430 can drive the front screen 410 to move linearly by 1cm-5cm, so as to ensure that the gas exchange channel formed between the front screen 410 and the end of the heat screen main body 300 has a larger area .

In a preferred embodiment, in order to further accelerate the cooling rate of the high temperature vacuum graphite sintering furnace 10 and shorten the cooling cycle, a cyclic cooling cavity 500 is formed between the heat shield main body 300 and the furnace barrel 100, and the cyclic cooling A partition 600 is disposed in the middle of the cavity 500 , and the partition 600 divides the circulating cooling cavity 500 into an air inlet cavity 510 and an air outlet cavity 520 . The high temperature vacuum graphite sintering furnace 10 further includes a cooling circulation fan 700, the inlet end of the cooling circulation fan 700 is provided with a circulation inlet pipe 710, the outlet end is provided with a circulation outlet pipe 720, and the circulation inlet pipe 710 communicates with the gas outlet cavity 520 , the circulation outlet pipe 720 communicates with the air intake cavity 510 .

Please refer to FIG. 4 together, the partition plate 600 is provided, the circulation cooling chamber 500 is divided into an air inlet chamber 510 at the front end and an air outlet chamber 520 at the rear end, and the inlet end of the cooling circulation fan 700 is communicated The outlet end of the air outlet chamber 520 communicates with the air inlet chamber 510 . After the sintering is completed and the temperature is lowered to an appropriate temperature, the driving member 430 applies a force to the front screen 410 away from the end of the heat screen main body 300, so that the front screen 410 is separated from the heat screen main body 300, Gas exchange channels are formed. The cooling circulation fan 700 is activated to extract the gas in the air outlet chamber 520 and circulate it into the air inlet chamber 510 through the circulation outlet pipe 720 . The gas in the air inlet cavity 510 enters the heat shield body 300 from the end of the heat shield body 300 along the gas exchange channel, and enters the heat shield body 300 along the gas exchange channel at the other end of the heat shield body 300 into the air outlet cavity 520 . In this way, the circulation of the gas phase is formed, thereby accelerating the cooling rate of the heat shield body 300, especially the space in the heat shield body 300, and further shortening the cooling cycle. Practice shows that when the heat shield end cover assembly 400 and the separator 600 are installed at the same time, the cooling cycle of the high temperature vacuum graphite sintering furnace 10 is shortened to within 60h by means of gas-phase circulation cooling.

Further, a cooling jacket 730 is provided on the outer side of the circulation inlet pipe piece 710 and/or the circulation outlet pipe piece 720 , and a cooling medium can be passed into the cooling jacket 730 . Preferably, the refrigeration medium is circulating water or chilled water. In the process of gas phase circulation cooling, a cooling medium is introduced into the cooling jacket 730 to cool the pipe wall of the circulation inlet pipe fitting 710 and/or the circulation outlet pipe fitting 720, and at the same time, part of the cold and hot circulating gas is cooled. Heat exchange, reduce the temperature of the circulating gas, and accelerate the cooling of the high-temperature vacuum graphite sintering furnace 10. At the same time, the cooling medium is introduced into the cooling jacket 730 to reduce the temperature of the pipe wall of the circulation inlet pipe 710 and/or the circulation outlet pipe 720 and protect the circulation inlet pipe 710 and/or the circulation outlet The pipe fitting 720 is protected from high temperature damage, thereby facilitating the establishment of the gas phase circulation of the high temperature vacuum graphite sintering furnace 10 at a higher temperature, and further shortening the cooling cycle. Practice has shown that by setting the cooling jacket 730, the gas phase circulation can be established when the gas phase temperature of the high temperature vacuum graphite sintering furnace 10 is 1000°C-1200°C, without causing any damage to the circulation inlet pipe 710 and/or the gas phase. The circulation outlet pipe 720 is damaged, so that the cooling cycle of the high-temperature vacuum graphite sintering furnace 10 can be greatly shortened, and the cooling rate can be increased. In the case where the heat shield end cap assembly 400 and the separator 600 are installed at the same time, the temperature can be reduced by circulating the gas phase and cooling the circulation inlet pipe 710 and/or the circulation outlet pipe 720 by water cooling. The cooling cycle of the high temperature vacuum graphite sintering furnace 10 is shortened to within 48h.

In one embodiment, the cooling circulating fan 700 includes a motor 701 , a radiator 702 and a water cooling cavity 703 disposed at the inlet end of the radiator 702 , and a water cooling coil 704 is disposed in or around the water cooling cavity 703 . Under the action of the back pressure of the radiator 702, the gas in the high temperature vacuum graphite sintering furnace 10 first enters the water cooling chamber 703 through the circulation inlet pipe 710, and after further cooling in the water cooling chamber 703, The air is blown into the air inlet cavity 510 through the radiator 702 to further increase the cooling rate and shorten the cooling cycle.

Further, in order to facilitate installation and improve water cooling efficiency, the cooling jacket 730 is arranged in sections. That is to say, on the circulation inlet pipe piece 710 and/or the circulation outlet pipe piece 720, the water-cooling jacket 730 is arranged on the circulation inlet pipe piece in sections with the place with the connecting flange as the segmented position. 710 and/or the outside of the circulation outlet pipe 720. On the one hand, it is convenient to manufacture and install the water cooling jacket 730, and on the other hand, the short flow of the water cooling jacket 730 is conducive to the rapid circulation of the refrigeration medium, thereby improving the cooling efficiency.

In some embodiments, a first shut-off valve 740 is provided on the circulation inlet pipe 710 or the circulation outlet pipe 720, and a connection pipe 750 is provided before the valve of the first shut-off valve 740. The connection pipe 750 A second shut-off valve 760 is provided, and the other end of the connecting pipe 750 is connected with a Roots blower 770 . Before the sintering operation, the second shut-off valve 760 is opened, and the circulating cooling chamber 500 is evacuated or replaced with an inert gas by the Roots blower 770 .

In some embodiments, the inlet end of the Roots blower 770 is connected to the heat shield body 300, so that the soaking zone in the heat shield body 300 can be evacuated or replaced with an inert gas before the sintering operation .

In some embodiments, the other end of the connecting pipe 750 is located in front of the Roots blower 770, and a dewaxing device 780 is further provided. The end is connected to the inlet of the Roots blower 770 . Before the sintering operation and after the sintering operation, the exhaust gas is first purified by the dewaxing device 780 and then discharged, so as to reduce the pollution of the sintering exhaust gas to the workshop environment.

Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a high-temperature vacuum graphite sintering furnace, comprising a furnace barrel and a furnace cover arranged at both ends of the furnace barrel, a heat shield main body is provided in the furnace barrel, and it is characterized in that, the inside of the furnace cover is provided with a heat shield end A cover assembly, the heat shield end cover assembly includes a front screen, a sliding rail and a driving member, the sliding rail is fixedly arranged on the furnace cover, the front screen is slidably arranged on the sliding rail, and the driving member The output end of the heat shield is connected to the front screen. When the furnace cover is closed on the furnace drum, the driving member can drive the front screen and the heat shield that are closed at the end of the heat shield body. Subject separation. 2 . The high-temperature vacuum graphite sintering furnace according to claim 1 , wherein the sliding rails are arranged along a cross-sectional direction perpendicular to the furnace cover, and sliding ears are provided on the sides of the front screen. 3 . It is slidably installed on the sliding rail, and the driving member is arranged at the rear end of the front screen to pull the front screen to slide along the sliding rail. 3. The high-temperature vacuum graphite sintering furnace according to claim 1 or 2, wherein a circulating cooling chamber is formed between the heat shield main body and the furnace barrel, and a partition plate is arranged in the middle of the circulating cooling chamber, The separator divides the circulating cooling chamber into an air inlet chamber and an air outlet chamber; The high temperature vacuum graphite sintering furnace also includes a cooling circulation fan, the inlet end of the cooling circulation fan is provided with a circulation inlet pipe, the outlet end is provided with a circulation outlet pipe, the circulation inlet pipe is connected to the air outlet cavity, and the circulation outlet The pipe piece communicates with the air intake cavity. 4 . The high temperature vacuum graphite sintering furnace according to claim 3 , wherein a cooling jacket is provided on the outer side of the circulation inlet pipe and/or the circulation outlet pipe, and the cooling jacket can be passed through the cooling jacket. 5 . refrigeration medium. 5 . The high temperature vacuum graphite sintering furnace according to claim 4 , wherein the cooling jacket is arranged in sections. 6 . 6 . The high temperature vacuum graphite sintering furnace according to claim 3 , wherein a first shut-off valve is provided on the circulation inlet pipe fitting or the circulation outlet pipe fitting, and a connection is provided in front of the valve of the first shut-off valve. 7 . The connecting pipe is provided with a second shut-off valve; the other end of the connecting pipe is connected with a Roots blower. 7 . The high temperature vacuum graphite sintering furnace according to claim 6 , wherein the inlet end of the roots blower communicates with the heat shield body. 8 . 8 . The high temperature vacuum graphite sintering furnace according to claim 6 , wherein the other end of the connecting pipe is located in front of the Roots blower, and is further provided with a dewaxing device; the air intake of the dewaxing device The end is connected to the connecting pipe, and the air outlet end is connected to the inlet of the Roots blower. 9 . The high-temperature vacuum graphite sintering furnace according to claim 3 , wherein the cooling circulating fan comprises a motor, a radiator and a water-cooling cavity arranged at the inlet end of the radiator, and the water-cooling cavity is provided with a Water cooling coil. 10. The high-temperature vacuum graphite sintering furnace according to claim 1 or 2, wherein the driving member can drive the front screen to move linearly by 1 cm-5 cm.

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