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CN1033745C - Automatic vacuum intermediate-frequency hot-pressing continuous sintering furnace - Google Patents

Automatic vacuum intermediate-frequency hot-pressing continuous sintering furnace Download PDF

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Publication number
CN1033745C
CN1033745C CN93117949A CN93117949A CN1033745C CN 1033745 C CN1033745 C CN 1033745C CN 93117949 A CN93117949 A CN 93117949A CN 93117949 A CN93117949 A CN 93117949A CN 1033745 C CN1033745 C CN 1033745C
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China
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workpiece
sintering
vacuum
heater
bell jar
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Expired - Fee Related
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CN93117949A
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CN1101311A (en
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孙立言
陈洪刚
李国林
伍洛长
李桃祁
田广忱
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Superhard Materials Inst Geological Prospecting Bureau No1 Ministry Of Metal
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Superhard Materials Inst Geological Prospecting Bureau No1 Ministry Of Metal
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Abstract

The present invention relates to an automatic vacuum intermediate frequency hot pressing continuous sintering furnace, which belongs to the technical field of the forming sintering equipment of a powder metallurgy product and a ceramic product, and production technology thereof. The present invention is composed of a sintering furnace body 1, a transition furnace body 2, a lifting bell jar 9, a rotation control disk 4, a pressurizing oil cylinder 3, a feeding and discharging oil cylinder 5, a four-column press 10, a lifting hydraulic cylinder 11 and an inductor 13. The present invention is provided with two stages of vacuum systems so that continuous vacuum heating and pressurizing sintering can be realized, and the present invention can be widely used for powder metallurgy and the vacuum hot pressing sintering production of ceramic products. The present invention obviously enhances the performance and the quality of the products and enhances production efficiency under the condition of similar cost.

Description

Full-automatic continuous fritting furnace of vacuum intermediate frequency hot pressing and method of operating thereof
The invention belongs to the technical field of power metallurgy equipment and production technology thereof.
Sintering is that powder or pressed compact are carried out high-temperature process to improve the technical process of workpiece mechanical performance in the temperature that is lower than its main component fusing point.It is the critical process that determines product quality, production efficiency and cost in powder metallurgy, pottery and the refractory industry.Mainly containing two kinds of sintering methods at present uses comparatively extensive.A kind of is earlier with the molded back of mixture cold sintering, and another kind is powder to be packed into carry out the compacting sintering moulding in the hot-die in heating, promptly is called pressure sintering.Sintering atmosphere is divided into sintering in air again, sintering and sintering in a vacuum in protective atmosphere.A large amount of tests show that vacuum heating-press sintering can make product non-oxidation, imporosity, few impurity and improve alloying level, thereby mechanical performance of products is obviously improved.
Although vacuum heating-press sintering technology is advanced technology, its extensive use has been subjected to the restriction of agglomerating plant performance.
The Ka Maite company of the U.S. in 1964 has designed continous way multistation vacuum sintering furnace, but does not have the hot pressing function." vacuum metallurgy " of publishing in March, 1988 mentioned the vacuum pressed sintering furnace of present maximum, but the diameter of heat-treatment part reaches 190.5mm, and the density that obtains sintered part can reach 99.7% of theoretical value, but can not be continuous.Provide a kind of vertical pressurization continuous fritting furnace and production method thereof among the Chinese patent application CN89106589X, but can not vacuumize.The automatic continous vacuum sintering furnace that CN89210197.0 provides does not have hot pressing.The continous vacuum sintering furnace that the clear 58-45304 of special permission communique of Japan provides does not have hot pressing.The clear 63-58201 of special permission communique provides a kind of continous way sintering furnace does not have vacuum and hot pressing.The continous vacuum sintering furnace of the clear 58-45304 of Japan's special permission communique does not have hot pressing.
At present the shortcoming of the batch (-type) vacuum heating-press sintering equipment that uses is that every sintering is finished a workpiece and wanted intermittently a period of time, the stop pumping vacuum, charges into air, opens fire door, takes out workpiece, the new workpiece of packing into then, closes upper furnace door, vacuumizes.Its complex operation, the intermittent time is long, and production efficiency is very low, so the scope of application of batch (-type) vacuum equipment is limited to.
Also there is not at present a kind of sintering furnace that can guarantee vacuum hotpressing continuous the time.
The objective of the invention is in order to overcome the deficiencies in the prior art, provide a kind of full-automatic continuous sintering furnace apparatus of vacuum intermediate frequency hot pressing and method of operating that can guarantee vacuum and hot pressing continuous the time.
The object of the present invention is achieved like this:
Apparatus of the present invention are a kind of by sintering furnace, the vacuum that press 10 and vavuum pump unit are formed, the full-automatic continuous fritting furnace of hot pressing, sintering furnace of the present invention comprises transition body of heater 2, liftable bell jar 9 and revolution siege 6, there is a cylindrical shape sintering body of heater 1 on the upper left side of cylindrical shape transition body of heater, use the mounting flange sealed attachment between the two, a centre bore 20 that allows workpiece 8 turnover is arranged between the two, there is a liftable bell jar 9 of cylindrical shape in the upper right side of transition body of heater 2, connect for the movable sealing flange between the two, a centre bore 22 that allows workpiece 8 turnover is arranged between the two, a revolution siege 6 that is used for laying with transmitting workpiece 8 is arranged in the transition body of heater 2, intermediate frequency inductor 13 and a last platen 12 that is fixed on the four post press 10 are housed in the said sintering body of heater 1, on four post press 10, be equipped with the lifting hydraulic cylinder 11 of a liftable bell jar 9, the control rotating disk 4 that the lower end of the central shaft 14 of said revolution siege 6 has a control revolution siege 6 to rotate by equal indicative, uniform six station holes 25 on circumference 24.
The method of operating of the full-automatic continuous fritting furnace of vacuum intermediate frequency hot pressing of the present invention is as follows:
1, will send into the workpiece in the atmosphere in the vacuum drying oven continuously, and the vacuum in the stove is not destroyed.Its method is: the station hole 25 of pallet 27 risings passing through revolution siege 6 is to bell jar 9, and the sealing device 28 that is installed in this moment under the pallet 27 seals hole 22, and the interior vacuum of stove is kept; Bell jar 9 inflation back is mentioned by hydraulic cylinder 11, and pallet 27 is exposed among the atmosphere, and manually can be contained in workpiece 8 on the pallet 27 this moment; Then bell jar 9 is fallen sealing, with the air in the second level vacuum system extraction bell jar 9; When pallet 27 descends workpiece 8 is fallen to being positioned at the station hole 25 of revolution siege 6.Because the air in the bell jar is drawn out of, so vacuum can be not destroyed in the stove when 27 and 28 descend.
2, the workpiece 8 that will send in the transition body of heater 2 is delivered to the eddy-current heating district continuously.Its method is: revolution siege 6 is a station calibration (n is the quantity of five equilibrium place work piece) by 360 °/n of control rotating disk 4 control rotational angles; Rotate and one by one workpiece 8 levels on the station hole 7 of aligning input and output material oil cylinder 5 to be transported on the station of aiming at pressurization oil cylinder 3 by this calibration; By its piston rod pallet 26 ascending motions workpiece 8 is delivered in the eddy-current heating district of sintering furnace.
3, to the pressurization in heating of the workpiece in the thermal treatment zone, carry out vacuum heating-press sintering.Temperature and press power (directly measuring with load sensor) are realized the microcomputer closed-loop control.Its method is: workpiece 8 enters behind the eddy-current heating district sealing device 30 with hole 20 sealings, and workpiece 8 is by last platen 12 location, and this moment, pallet 26 moved workpiece 8 pressurizations on continuing, and this press power is provided by hydraulic power unit and by the microcomputer closed-loop control.Eddy-current heating is provided by intermediate frequency power supply, and its sintering temperature is by the microcomputer closed-loop control.Temperature, pressure is recorded the curve of time and shows.
4, under the workpiece finished of sintering from induction zone, again can be under the condition of not destroying vacuum in the stove workpiece be sent in stove among the atmosphere outside the stove.Its method is: the intact workpiece 8 of sintering falls within the station hole 25 of revolution siege 6 from the eddy-current heating district along with pallet 26 descends; Along with calibration rotates and the station 7 of arrival input and output material oil cylinder 5 alignings; Pallet 27 rises workpiece 8 is held up and is parked in the bell jar 9, and this moment, sealing device 28 was with centre bore 22 sealings; After charging into air in the bell jar 9, promoting hydraulic cylinder 11 can mention bell jar 9, and workpiece 8 is exposed among the atmosphere.Can take the workpiece of burning-out this moment away, can change the workpiece that does not burn simultaneously again.Carry out each above-mentioned step again.
Below in conjunction with accompanying drawing the full-automatic continuous fritting furnace of vacuum intermediate frequency of the present invention hot pressing is described in detail:
Fig. 1 is the structural representation of sintering furnace of the present invention.
Fig. 2 is that the A of Fig. 1 is to view schematic diagram (establishing hole count n=6).
Fig. 3 is the local amplification view of C-C (B-B) among Fig. 1.
Vacuum intermediate frequency hot pressing continuous fritting furnace of the present invention is mainly by sintering body of heater 1, transition body of heater 2, and liftable bell jar 9, control rotating disk 4, revolution siege 6, pressurization oil cylinder 3, input and output material oil cylinder 5, four post press 10 promote hydraulic cylinder 11 and intermediate frequency inductor 13 is formed.Wherein, there is a cylindrical shape sintering body of heater 1 on the upper left side of cylindrical shape transition body of heater 2, uses the mounting flange sealed attachment between the two, and a centre bore 20 that allows workpiece 8 turnover is arranged between the two; There is a liftable bell jar 9 of cylindrical shape in the upper right side of transition body of heater 2, bell jar 9 is the loose flange sealed connection with transition body of heater 2, a centre bore 22 that allows workpiece 8 turnover is arranged between the two, a revolution siege 6 that is used for laying with transmitting workpiece is arranged in the transition body of heater 2, intermediate frequency inductor 13 and a platen 12 that is fixed on the four post press 10 are housed in the sintering body of heater 1, there is the vacuum-pump line 21 of a band vacuum dish valve 19 to be communicated with on the barrel of sintering body of heater 1, a safety discharging air valve 29 is arranged on pipeline 21 with one group of vavuum pump.There is a vacuum pumping hole 23 to be communicated with on the base below the bell jar 9, on four post press 10, is equipped with the lifting hydraulic cylinder 11 of a liftable bell jar 9 with another group vavuum pump.There is the control rotating disk 4 that a control revolution siege 6 rotates by circumference equal indicative angle α (α=360 °/n is a station calibration, and n is the quantity of laying the station hole of workpiece) lower end of central shaft 14 of revolution siege 6.The calibration rotation of control rotating disk 4 is finished by hydraulic-driven cam or stepper motor driving, rotates and workpiece can be delivered to each station successively by this calibration.Be uniform-distribution with n station hole 25 on the circumference 24 of revolution siege 6, n can decide as required.N is a positive integer.Workpiece 8 is placed on the station hole 25.The central axis of sintering body of heater 1 and bell jar 9 and circumference 24 intersect vertically, a pressurization oil cylinder 3 and an input and output material oil cylinder 5 that is fixedly connected on press 10 is arranged below the bottom of transition body of heater 2, pressurization oil cylinder 3 is positioned on the central axis of sintering body of heater 1, and input and output material oil cylinder 5 is positioned on the central axis of bell jar 9.There is a piston rod pallet 26 that is used for transporting workpiece the piston rod end of pressurization oil cylinder 3, in its bottom a sealing device 30 that is used for closed hole 20 is arranged, pallet is sent into workpiece 8 in the sintering body of heater 1 by station hole 25 and centre bore 20, sealing device 30 is with hole 20 sealings simultaneously, make a high and stable vacuum is arranged in the sintering body of heater 1, the piston rod end of input and output material oil cylinder 5 also is equipped with a pallet 27 that is used for transporting workpiece and one and is positioned at and is used for the sealing device 28 in center seal hole 22 below the pallet 27, pallet 27 is sent into workpiece 8 in the bell jar 9 by station hole 25, and sealing device 28 is then with centre bore 22 sealings.The structure of pallet 27 and sealing device 28 is, a heat resistant pad 31 is arranged on the pallet 27, be sealing device 28 below, it is by temperature resistant encapsulation cushion rubber 33, upper gasket 34, butterfly spring group 35 and lower gasket 36 constitute, and above-mentioned member is installed on the piston rod 37 of input and output material oil cylinder 5, and piston rod all adopts vacuum dynamic seal to cooperate with body of heater.Pallet 26 is same as described above with the structure of sealing device 30.
The vavuum pump unit of the sintering body of heater 1 among the present invention, transition body of heater 2, liftable bell jar 9 and vacuum-pump line 21 UNICOMs by sintering furnace 1 is formed first order vacuum system; The bell jar 9 that is sealed by sealed device 28 and form second level vacuum system by another group vavuum pump unit that vacuum pumping hole 23 connects.
The above action follow procedure workpiece of promptly can realizing being back to back is realized continuous sintering again.The accuracy of each step action interlock is guaranteed by the PC of the whole switching values of control.The closed-loop control precision of analog quantity is guaranteed by industrial computer.All the unified management of switching value and analog quantity and record demonstration are finished by computer center.Vacuum range is by vacuum meter indication and warning, but artificial regulatory, but also closed-loop control.First order vacuum system is closed vacuum dish plate valve 19 after obtaining working vacuum, and the safety discharging air valve 29 on the opening conduits can charge into the following inert gas of 0.1MPa, implements neutral atmosphere protection hot pressed sintering.Pressure increases because gas is subjected to heat expansion in sintering process, so safety discharging air valve 29 is connected the safe pressure limiting state that is in all the time.
Equipment provided by the present invention and method can adopt microcomputer closed-loop control or manual operation intermediate frequency power supply by the temperature rule of setting the sintering workpiece to be carried out eddy-current heating in the vacuum ranges of design code; Adopt microcomputer closed-loop control or manual operation hydraulic power unit to exert pressure to the sintering workpiece simultaneously by setting rule; All the step switch amount is by the PC programme-control; Show by computer center unified management and record, thereby realize full-automatic continous vacuum sintering.Advantage of the present invention is the performance and the quality that still can guarantee product under the prerequisite that has obviously improved production efficiency.The present invention can be widely used in the vacuum heating-press sintering production of powder metallurgy and ceramic product, is more suitable in the development and the production of high strength, high density, high quality powder metallurgy and ceramic material.For The Application of Technology such as evacuated die-casting process, soldering, joint, vacuum hotpressing processing, balanced hot-pressing processing provide equipment.

Claims (5)

1, a kind of by sintering furnace, the full-automatic continuous fritting furnace of vacuum hotpressing that press (10) and vavuum pump unit are formed, it is characterized in that said sintering furnace comprises transition body of heater (2), liftable bell jar (9) and revolution siege (6), there is a cylindrical shape sintering body of heater (1) on the upper left side of cylindrical shape transition body of heater, use the mounting flange sealed attachment between the two, a centre bore (20) that allows workpiece (8) turnover is arranged between the two, there is a liftable bell jar of cylindrical shape (9) in the upper right side of transition body of heater (2), connect for the movable sealing flange between the two, a centre bore (22) that allows workpiece (8) turnover is arranged between the two, a revolution siege (6) that is used for laying with transmitting workpiece 8 is arranged in the transition body of heater (2), intermediate frequency inductor (13) and a last platen (12) that is fixed on the four post press (10) are housed in the said sintering body of heater (1), on four post press (10), be equipped with the lifting hydraulic cylinder (11) of a liftable bell jar (9), the lower end of the central shaft (14) of said revolution siege (6) has a control revolution siege (6) press the control rotating disk (4) that equal indicative rotates, uniform n station hole (25) on circumference (24).
2, sintering furnace as claimed in claim 1, the central axis and the circumference (24) that it is characterized in that sintering body of heater (1) and bell jar (9) intersect vertically, a pressurization oil cylinder (3) and an input and output material oil cylinder (5) that is fixedly connected on press (10) is arranged below the bottom of transition body of heater (2), pressurization oil cylinder (3) is positioned on the central axis of sintering body of heater (1), input and output material oil cylinder (5) is positioned on the central axis of bell jar (9), the tailpiece of the piston rod of pressurization oil cylinder (3) is equipped with one and is used for the pallet (26) of amplifier workpiece and the sealing device (30) of center seal hole (20), the piston rod end of input and output material oil cylinder (5) is equipped with one and is used for the sealing device (28) of center seal hole (22) and the pallet (27) that is used for transporting workpiece, sealing device (28) be positioned at pallet (27) below.
3, sintering furnace as claimed in claim 1 is characterized in that sintering body of heater (1), transition body of heater (2), liftable bell jar (9) and the vavuum pump unit composition first order vacuum system that connects with the vacuum-pump line (21) that passes through on the sintering body of heater (1); The bell jar (9) that is sealed by sealed device (28) and form second level vacuum system by another group vavuum pump unit that its vavuum pump interface (23) connects.
4, the method for operating of the full-automatic continuous fritting furnace of a kind of vacuum hotpressing as claimed in claim 1 is characterized in that:
(1) to send into the workpiece in the atmosphere in the vacuum drying oven continuously, and do not destroy vacuum in the stove, its method is: pallet (27) rises and passes through to turn round the station hole (25) of siege (6) to bell jar (9), the sealing device (28) that be installed under the pallet (27) this moment seals centre bore (22), make and keep vacuum in the transition body of heater (2), mention by promoting hydraulic cylinder (11) bell jar (9) inflation back, pallet (27) is exposed among the atmosphere, be contained in workpiece (8) on the pallet (27) this moment, then bell jar (9) is fallen sealing, extract the interior air of bell jar (9) out with second level vacuum system, when pallet (27) descends workpiece (8) is fallen to being positioned at the station hole (25) of revolution siege (6);
(2) workpiece (8) that will send in the transition body of heater (2) is delivered to the eddy-current heating district continuously, its method is: revolution siege (6) is by each 360 °/n of the station calibration angle of rotating of control rotating disk (4) control, workpiece (8) level that to aim at one by one on the station of input and output material oil cylinder (5) is transported on the station of aiming at pressurization oil cylinder (3), by pallet (26) ascending motion workpiece (8) is delivered in the eddy-current heating district in the sintering furnace (1) again;
(3) to the pressurization in heating of the workpiece in the thermal treatment zone, carry out vacuum heating-press sintering, its method is: after workpiece (8) enters the eddy-current heating district, sealing device (30) is with hole 20 sealings, workpiece (8) is located by last platen (12), move on pallet this moment (26) continues workpiece (8) pressurization, provide eddy-current heating by intermediate frequency power supply;
(4) under the workpiece finished of sintering from induction zone, under the condition of not destroying vacuum in the stove, workpiece is sent in stove the atmosphere outside the stove, its method is: the intact workpiece (8) of sintering is positioned at the station hole (25) of revolution siege (6) with landing under the pallet (26) from the eddy-current heating district, rotate the station (7) that arrives input and output material oil cylinder (5) correspondence with its calibration, pallet (27) rises workpiece (8) is held up and is parked in the bell jar (9), sealing device this moment (28) seals centre bore (22), charge in the bell jar (9) and promote hydraulic cylinder (11) behind the air bell jar (9) is mentioned, workpiece (8) is exposed among the atmosphere, take the workpiece (8) of burning-out this moment away, change the workpiece that does not burn simultaneously, carry out each above-mentioned step again.
5, as right 4 described methods; it is characterized in that said first order vacuum system obtains to close the vacuum dish valve (19) on the vacuum pump line pipe (21) after the working vacuum degree, open safety discharging air and cut down (29); charge into inert gas, implement neutral atmosphere protection sintering.
CN93117949A 1993-10-05 1993-10-05 Automatic vacuum intermediate-frequency hot-pressing continuous sintering furnace Expired - Fee Related CN1033745C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN93117949A CN1033745C (en) 1993-10-05 1993-10-05 Automatic vacuum intermediate-frequency hot-pressing continuous sintering furnace

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Application Number Priority Date Filing Date Title
CN93117949A CN1033745C (en) 1993-10-05 1993-10-05 Automatic vacuum intermediate-frequency hot-pressing continuous sintering furnace

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CN1101311A CN1101311A (en) 1995-04-12
CN1033745C true CN1033745C (en) 1997-01-08

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Families Citing this family (6)

* Cited by examiner, † Cited by third party
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JP2004210593A (en) * 2002-12-27 2004-07-29 National Institute Of Advanced Industrial & Technology Centrifugal sintering equipment
CN100429469C (en) * 2006-03-31 2008-10-29 沈阳威泰科技发展有限公司 Vacuum-hot pressing sintering furnace
CN100519007C (en) * 2006-12-29 2009-07-29 上海广益高温技术实业有限公司 Rotary high temp sintering device
CN101264516B (en) * 2008-01-04 2010-12-15 中国科学院上海硅酸盐研究所 Array double-action continuous workpiece vacuum hot pressing device
CN105901469A (en) * 2016-06-29 2016-08-31 江苏楷益智能科技有限公司 Continuous food sterilization device
CN111158412B (en) * 2020-03-25 2021-04-27 湖南飞沃新能源科技股份有限公司 Bar-shaped object heating device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2044710U (en) * 1989-03-06 1989-09-20 吴胜久 Automatic and continuous vacuum sintering furnace

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2044710U (en) * 1989-03-06 1989-09-20 吴胜久 Automatic and continuous vacuum sintering furnace

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